Geography Of The India

Answer : The country’s total population, as recorded in Census 2011, at 1.21 billion, is slightly more than what was forecast. But the population growth rate has decelerated from 1.97 per cent per annum between 1991 and 2001, to 1.64 per cent per annum between 2001 and 2011. Notably, it declined in almost every State including those of the populous Gangetic plains. The deceleration reflects a much-needed decline in the Total Fertility Rate (TFR) which is estimated to have fallen to 2.6 per cent and is expected to decline to 2.3 per cent in the first half of the present decade. The Southern States have reached, or are close to reaching, the replacement level of fertility. Fertility levels in the northern states are also falling, but are still much higher than the replacement level.

India has a younger population not only in comparison to advanced economies but also in relation to the large developing countries. As a result, the labour force in India is expected to increase by 32 per cent over the next 20 years, while it will decline by 4.0 per cent in industrialised countries and by nearly 5.0 per cent in China. This ‘demographic dividend’ can add to growth potential, provided two conditions are fulfilled. First, higher levels of health, education and skill development must be achieved. Second, an environment must be created in which the economy not only grows rapidly, but also enhances good quality employment/livelihood opportunities to meet the needs and aspirations of the youth.

Current status of the population policy of India: National Population Policy of India was formulated in the year 2000 with the long term objective of achieving a stable population by 2045, at a level consistent with the requirements of sustainable economic growth, social develo-pment, and environmental protection.

The immediate objective of the policy is to address the unmet needs for contraception, health care infrastructure, and health personnel, and to provide integrated service delivery for basic reproductive and child health care. National Population Policy pursues to achieve following Socio-Demographic goals:

• Address the unmet needs for basic reproductive and child health services, supplies and infrastructure.
• Make school education up to age 14 free and compulsory, and reduce drop outs at primary and secondary school levels to below 20 percent for both boys and girls.
• Reduce infant mortality rate to below 30 per 1000 live births.
• Reduce maternal mortality ratio to below 100 per 100,000 live births.
• Achieve universal immunization of children against all vaccine preventable diseases.
• Promote delayed marriage for girls, not earlier than age 18 and preferably after 20 years of age.
• Achieve 80 percent institutional deliveries and 100 percent deliveries by trained persons.
• Achieve universal access to information/counseling, and services for fertility regulation and contraception with a wide basket of choices.
• Achieve 100 per cent registration of births, deaths, marriage and pregnancy.
• Contain the spread of Acquired Imm-unodeficiency Syndrome (AIDS), and promote greater integration between the management of reproductive tract infections (RTI) and sexually transmitted infections (STI) and the National AIDS Control Organization.
• Prevent and Control communicable diseases. Integrate Indian Systems of Medicines (ISM) in the provision of reproductive and child health services, and in reaching out to households.
• Promote vigorously the small family norm to achieve replacement levels of TFR. Bring about convergence in implementation of related social sector programs so that family welfare becomes a people centered prog-ramme.

Answer : In the year of 2014 there was monsoonal delay and related extreme weather were likely amplified by a combination of record atmospheric heat due to human-caused greenhouse gas forcing and a growing and strengthening El Nino. In 2014 April, global atmospheric temperatures hit new record highs of +0.91 degree Celsius above 1880s values even as El Nino rapidly gained ground in the Pacific through May 2014.

• For India, history shows numerous cases of severe monsoonal disruption during strong, moderate, and, recently, even weak El Nino events. In addition, record high atmospheric temper-atures enhance extreme drought and flood poten-tials by amping up the hydrological cycle and thus increasing the rate of both evaporation and precipitation. Storms, where they do occur tend to be both tall and abnormally powerful under current human-warming related stresses even as droughts tend to develop with higher velocity and to persist for longer periods.
• It is possible, due to both changes to the hydrological cycle and to atmospheric circulation, that the Indian monsoon has become even more sensitive to the El Nino pattern under current human-caused warming. 2014’s monsoonal delay with El Nino just emerging shows an almost instant response to the forcing coming from increased temperatures in the Equatorial Pacific. As such, conditions of heightening threat for crop damage throughout a land where 1.25 billion people rely on the annual rains are a critical issue.
• Extraordinary sea surface temperature anomalies in the Northeast Pacific including numerous pools of +2.25 to +4 degree Celsius or higher departures are indicative of both a strengthening El Nino pattern and a general warming of Ocean surface waters through human greenhouse gas heat forcing.
• Overall, the forecast remains for continued monsoonal delay and disruption, continued heat waves and likelihood for extreme rainfall and storms in the regions where the monsoon finally arrives. With El Nino conditions in place over the Pacific now, with atmospheric temperatures rising into record range, and with an official El Nino status likely to be declared by summer, this forecast is lent yet more certainty and urgency.

Answer : Modern architecture is no doubt based on scientific principles, but at the same time it needs to be made sustainable to the urban environment. At the same time modern architecture calls for massive vertical development and horizontal expansion which increases the pressure on the cities and metros and develops special needs which need to be cleared too.

• Urban planning provides suitable solutions which are not only effective but sustainable as well in the long run. It works on principles such that - urban positives could be enhanced, while the urban challenges such as slums, pollution, sewage disposal, congestion, traffic bottlenecks, etc. could be checked. It also enhances the layout of the various nodes of the city and their functions by laying out a master-plan and sub-plans for specific and potential needs of various regions.
• It focuses on development of robust infrast-ructure division of public and private land, ensures water availability and effective sewage disposal, fast means of transport, promotes clean and green energy, promotes greening of cities for sustainable development, etc.
• The government has come up with programmes like JNNURM to further enhance the same and schemes like Rajiv Awas Yojana to eliminate slums and form inclusive and equitable cities in which every citizen has access to basic infrastructure.
• Similarly, in the current budget speech, the finance minister spoke of developing smart cities which will be effectively integrated with robust infrastructure and sustainable development shall not be compromised with.

Answer : The idea of linking water surplus Himalayan rivers with water scarce parts of western and peninsular India has been doing the rounds for the past 150 years.

The Project that the Supreme Court and the President have enjoined the government of India to implement may well be the largest infrastructure project ever undertaken in the world, to transfer water from the surplus river basins to ease the water shortages in western and southern India while mitigating the impacts of recurrent floods in the Eastern India. It will build 30 links and some 3000 storages to connect 37 Himalayan and Peninsular rivers to form a gigantic South Asian water grid. The canals, planned to be 50 to 100 meters wide and more than 6 meters deep, would facilitate navigation

Pros:

1. India receives most of its rain during monsoon season from June to September, mostof it falls in northern and eastern part of India, the amount of rainfall in southern and western part are comparatively low. It will be these places which will have shortage of water. Interlinking of rivers will help these areas to have water throughout the year.
2. The main occupation of rural India is agriculture and if monsoon fails in a year, then agricultural activities come to a standstill and this will aggravate rural poverty. Interlinking of rivers will be a practical solution for this problem, because the water can be stored or water can be transferred from water surplus area to deficit.
3. The Ganga Basin, Brahmaputra basin sees floods almost every year. In order to avoid this, the water from these areas has to be diverted to other areas where there is scarcity of water. This can be achieved by linking the rivers. There is a two way advantage with this - floods will be controlled and scarcity of water will be reduced.
4. Inter-linking of rivers will also have commercial importance on a longer run. This can be used as inland waterways and which helps in faster movement of goods from one place to other.
5. Interlinking creates a new occupation for people living in and around these canals andit can be the main areas of fishing in India.

Problems from Inter-linking or Rivers: The Indian proposal for the mega project of inter-linking of rivers (ILR) has come at a time when large dams and canal infrastructure are facing an sall-time low. Environmental groups are seriously questioning the ecological costs of large dams; and other NGOs are asking whether the human displacement and misery these cause, given India's poor track record of rehabilitation of the displaced populations, would permit these to pass an objective social cost-benefit test. To add to these, the performance of public irrigation projects has continuously been slipping. Finally, there is widespread questioning of the justification for such investment when agriculture is shrinking in water-scarce western and peninsular India and future food demand appear largely over-projected.

Answer : Petroleum is not distributed evenly around the world. More than half of the world's proven oil reserves are located in the Middle East (including Iran but not North Africa); that is to say, the Middle East contains more oil than the rest of the world combined. Following the Middle East are Canada and the United States, Latin America, Africa, and the region occupied by the former Soviet Union. Each of those regions contains less than 15 percent of the world's proven reserves. (Reserves are identified quantities of "in-place" petroleum that are considered recoverable under current economic and technological conditions. Estimated by petroleum engineers and geologists using drilling and production data along with other subsurface information, the figures are revised to include projected field growth as development progresses.)

Some Factors Causing Decrease in oil prices

• Strengthening of US dollar
• Weak global demand
• More supplies from Russia
• Iran nuclear deal put off the sanctions on Iran and now Iran also adding to the oil supply.

Strategic relevance for India

• Now India can forge this opportunity to build strategic oil reserves for securing its energy needs.

Answer : Locational factors:

1. Generally found near tropics due to plentiful insolation
2. Preferably at drier place where atmospheric disturbance is very low
3. At desert or barren land as it needs larger area

Thus India natural location to harness solar energy

Indian government initiative

1. JNNSM
2. New Indian policy that have dual energy transfer (home producing and selling to electricity boards)
3. Under UNFCCC where serious concern is being made over GHG solar energy is a significant alternative

Constraint: Developing countries having larger potential do not harness it owing to technological and financial constraints

• Causes of regional inequalities
• Geographic isolation
• Inadequacy of economic overheads such likes transport, labour, technology, etc.
• Lower investment and financial assistance
• Inadequate human development

Whether it is economic or social factors that fuelled one another?

• Social factors such as religion, gender issues - while not primary obstacles to economic development, these can also slow down economic growth and limit economic development of regions or states and thus contributes to regional inequalities.
• Social customs and attitudes of the people of backward countries are barrier to economic progress. Conservatism, superstition, lack of ambition, undue regard for custom and status are a drag on economic progress. Economic backwardness in India is in no small measure due to joint family system, caste system, peculiar laws of inheritance and the other-worldly attitude of the people.

Answer : Soil is our life support system. Soils provide anchorage for roots, hold water and nutrients. Soils are home to myriad micro-organisms that fix nitrogen and decompose organic matter, and armies of microscopic animals as well as earthworms and termites. We build on soil as well as with it and in it

Soil plays a vital role in the Earth's ecosystem. Without soil human life would be very difficult. Soil provides plants with foothold for their roots and holds the necessary nutrients for plants to grow; it filters the rainwater and regulates the discharge of excess rainwater, preventing flooding; it is capable of storing large amounts of organic carbon; it buffers against pollutants, thus protecting groundwater quality; it provides Man with some essential construction and manufacturing materials; it also presents a record of past environmental conditions

Soil functions are general capabilities of soils that are important for various agricultural, environmental, nature protection, landscape architecture and urban applications. Six key soil functions are:

1. Food and other biomass production
2. Environmental Interaction: storage, filtering, and transformation
3. Biological habitat and gene pool
4. Source of raw materials
5. Physical and cultural heritage
6. Platform for man-made structures: buildings, highways

Soil and food production: Soils provide a basic medium for plant growth, underpinning the production of crops and fodder and facilitate a range of ecosystem services, including nutrient cycling, water regulation and supporting biodiversity. Food availability relies on soils: nutritious and good quality food and animal fodder can only be produced if our soils are healthy. A healthy living soil is therefore a crucial ally to food security and nutrition.

Problems faced by Indian Soil: Indian soils are suffering from a number of problems like (i) soil erosion, (ii) fertility loss, (iii) desertification, (iv) waterlogging (v) salinity and alkalinity, (vi) wasteland (vii) urbanisation and transport development, and (viii) interference of man.

Answer : Following are some of the Factors:

• Historic significance: The British and Portuguese influence turned the city of Surat into an important port city and a vital business hub. In the turn of 20th century, the city started its journey to become the nerve center of the diamond industry in the country. According to the local lore the initial set up was based on the expertise of the East African diamond cutters who were brought to the Indian shores in the early years of the past century.
• Traditional expertise: Like the orthodox Jewish communities that helped earn Antwerp its name in the world diamond circuit, it is the close knit religious community called the Palanpuri Jains, who remain the main author of Surat's success story in the trade of diamond jewelries.
• Cheap labour
• Era of 1970s:the success story of Surat actually gained prominence in the 1970's when the Indian diamond dealers started importing low-quality gemstones, and exporting them to the U.S. after turning them into dazzling pieces with their unmatched cutting and polishing skills.

Answer : The Himalayas, as a great climatic divide affecting large systems of air and water circulation, help determine meteorological conditions in the Indian subcontinent to the south and in the Central Asian highlands to the north.

• By virtue of its location and stupendous height, the Great Himalaya Range obstructs the passage of cold continental air from the north into India in winter and also forces the southwesterly monsoon (rain-bearing) winds to give up most of their moisture before crossing the range northward. The result is heavy precipitation (both rain and snow) on the Indian side but arid conditions in Tibet. The average annual rainfall on the south slopes varies between 60 inches (1,530 mm) at Shimla, Himachal Pradesh, and Muss-oorie, Uttarakhand, in the western Himalayas and 120 inches (3,050 mm) at Darjiling, West Bengal state, in the eastern Himalayas. North of the Great Himalayas, at places such as Skardu, Gilgit, and Leh in the Kashmir portion of the Indus valley, only 3 to 6 inches (75 to 150 mm) of precipitation occur.

Answer : Landform, whether large or small result from the interaction of certain forces, they accomplish their work by various means of processes, which may be described as geologic, Climatic and biologic and these processes bring about the changes in the Earth's surface which may be Classified as.

(I)Long Period Changes (Man Is unable to notice this change) and

(II)Short period Changes. The forces which affect the crust of the earth are broadly classified in two types

Endogenetic forces: The forces coming from within the earth are called as Endogenetic forces which causes two types of movement in the earth viz (I) Horizontal movements (II) Vertical movements. In the basis of intensity the Endogenetic forces and movements are divided in to two major Categories

1.Sudden Forces

2.Diastrophic Forces

Exogenetic Forces: The exogenetic forces or Processes, also called as denudational processes, or 'destructional forces or processes' are originated from the atmosphere. These forces are continuously engaged in the destruction of the relief features created by Endogenetic forces through their weathering, erosional, depositional activities. Denudation includes both weathering and erosion where weathering being a static process includes the disintegration and decomposition of rocks in situ whereas erosion is dynamic process which includes both, removal of materials and their transportation to different destinations.

Answer : El Nino: El Niño means The Little Boy, or Christ Child in Spanish. The term El Niño refers to the large-scale ocean-atmosphere climate interaction linked to a periodic warming in sea surface temperatures across the central and east-central Equatorial Pacific. Typical El Niño effects are likely to develop over North America during the upcoming winter season. Those include warmer-than-average temperatures over western and central Canada, and over the western and northern United States. Wetter-than-average conditions are likely over portions of the U.S. Gulf Coast and Florida, while drier-than-average conditions can be expected in the Ohio Valley and the Pacific Northwest. The presence of El Niño can significantly influence weather patterns, ocean conditions, and marine fisheries across large portions of the globe for an extended period of time.

Impact on India Climate: Generally, El Nino and the Indian Monsoon rains are inversely related. Trade winds coming from South America normally blow westward towards Asia during Southwest Monsoon. Warming of the Pacific Ocean results in weakening of these winds. Therefore, moisture and heat content gets limited and results in reduction and uneven distribution of rainfall across the Indian sub-continent.

Does El Nino always lead to droughts in India?

• The most prominent droughts in India, six of them, since 1871 have been El Nino triggered droughts, including the recent ones that occurred in 2002 and 2009. Nevertheless, it is important to note that all El Nino years do not lead to drought in India. The year 1997-98 is a stark reminder as it was a strong El Nino year but that did not cause drought in India, in fact, rainfall was in excess. On the other hand, a moderate El Nino in 2002 resulted in one of the worst droughts.
• Going by historical data of 135 years from 1880 to 2014, about 90% of all evolving El Nino years have led to below normal rainfall and 65% of evolving El Nino years have brought droughts. From this fact, one thing is clear that El Nino years adversely affect the weather in India in terms of Monsoon rain, with very few exceptions. During an El Nino year, the rainfall is generally below the normal average, which has its negative bearing on crop production.

Answer : Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves that make the ground shake. When two blocks of rock or two plates are rubbing against each other, they stick a little. They don't just slide smoothly; the rocks catch on each other. The rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up. When the rocks break, the earthquake occurs. During the earthquake and afterward, the plates or blocks of rock start moving, and they continue to move until they get stuck again. The spot underground where the rock breaks is called the focus of the earthquake. The place right above the focus (on top of the ground) is called the epicenter of the earthquake.

Why earthquake can't be predicted?

• Though scientists do create sophisticated models of earthquakes and study the history of quakes along fault lines, no one has enough of an understanding about the conditions-the rock materials, minerals, fluids, temperatures, and pressures-at the depths where quakes start and grow to be able to predict them. "We can create earthquakes under controlled conditions in a laboratory, or observe them close-up in a deep mine, but those are special situations that may not look very much like the complicated faults that exist at depth in the crust where large earthquakes occur,"Michael Blanpied, associate coordinator of the USGS Earthquake Hazards Program. "Our observations of earthquakes are always at a distance, viewed indirectly through the lens of seismic waves, surface faulting and ground deformation. To predict earthquakes, we would need to have a good understanding of how they occur, what happens just before and during the start of an earthquake, and whether there is something we can observe that tells us than an earthquake is imminent. So far, none of those things are known."
• According to Blanpied, the current understanding is that quakes start or nucleate small, on an isolated section of the fault, and then grow quickly. "That nucleation can occur anywhere, and even when we have examples of repeated earthquakes, they may nucleate in different places," he says. "If there is a process that occurs in the seconds-[or] minutes, hours, months-before an earthquake, that process may be very subtle and hard to observe through miles of solid rock, especially when we don't even know where to look."
• Another challenge: Big and small quakes might not start differently. "If all earthquakes start small and some just happen to grow big, and then prediction may be a lost cause, because we're not at all interested in predicting the thousands of tiny earthquakes that happen every day."

Answer : Impacts of Temperature Inversion

1. It leads to formation of Fog due to the presence of warm air above the cold air. The cold air cools the warm air from below thus forms the tiny droplets around dust particles and smokes during winter season that result in formation of fog.
2. The urban smog is formed by the intensification of fog by pollution. When smog gets mixed with sulphur dioxide it becomes poisonous and deadly for human beings.
3. Inversion of temperature leads to formation of frost. Frost is economically unfavourable weather phenomenon as it damages fruit orchids and crops.

The inversion of temperatures creates anticyclonic conditions thus inhibits rainfall and encourages dry conditions.

Answer : When an earthquake occurs the seismic waves (P and S waves) spread out in all directions through the Earth’s interior. Seismic velocities depend on the material properties such as composition, mineral phase and packing structure, temperature, and pressure of the media through which seismic waves pass.

• Seismic waves travel more quickly through denser materials and therefore generally travel more quickly with depth. Anomalously hot areas slow down seismic waves. Seismic waves move more slowly through a liquid than a solid.
• Molten areas within the Earth slow down P waves and stop S waves because their shearing motion cannot be transmitted through a liquid. Partially molten areas may slow down the P waves and attenuate or weaken S waves.
• Thus through the scientific study and analysis of various seismic waves of natural and man induced earthquakes unrevealed the mystery of earth’s interior and divided the earth in three different layers Crust, Mantle and Core.

Answer : Features of Tropical cyclone

• Tropical Cyclones are climatological pheno-mena that occurs across the globe. They have certain characteristics that distinguish it from other atmospheric disturbances. These are:
• The foremost characteristic is that tropical cyclones are most violent and most disastrous of all the atmospheric disturbances.
• The average speed is 120 kmph, although it may vary from 32 kmph to 200 kmph or more. At times it reaches 400 kmph also.
• They have closed isobars. The pressure gradient is very sharp. More closely spaced isobars represent greater velocity of the storm and viceversa. The pressure at the centre is extremely low. The winds from the surrounding area are drawn towards this low-pressure core called the “eye” of the cyclone.
• Tropical cyclones develop over oceans and seas only. They are most violent and vigorous over water.
• On landfall, their velocity decreases due to friction, and as the source of energy is cut off, they dissipate soon. Thus they affect the coastal areas only.
• The movement of tropical cyclone is affected by the prevailing wind system. Normally they move from east to west under the influence of trade winds.
• They are seasonal in nature and occur during a specific period of the year only.

Answer : Location refers to the physical location of a company whereas the localization industry consists of companies that provide translation and communication services for businesses that want to customize their product and marketing communications for local markets around the world.

• The industry meets the needs of companies that market their products and services globally, but want to ensure that their communications meet local, cultural, language, political, legal and business requirements. Thus Localization refers to the efforts of a company to tailor their products towards a certain region i.e. changing the products according to the local needs.

Answer : Floods are caused by the following factors either singly or in combination: excessive precipitation, inadequate river channel capacity, obstruction in streams, inadequate waterways at the confluences, human encroachments, and lack of adequate drainage, failure of flood control embankments and deforestation.

• Positive impact of flooding in Ganges/Brahmaputra river basin - Regular annual flooding is essential to people who live on the flood plain of these rivers, the farming season is planned around the floods, rice is the main crop and requires large quantities of water. Also, when the river floods it leaves behind fertile silt.
• Floods have significant consequences for the environment. Floods play an important role in maintaining key ecosystem functions and biodiversity. They link the river with the land surrounding it, recharge groundwater systems, fill wetlands, increase the connectivity between aquatic habitats, and move both sediment and nutrients around the landscape, and into the marine environment. For many species, floods trigger breeding events, migration, and dispersal. These natural systems are resilient to the effects of all but the largest floods.
• Floods have large social consequences for communities and individuals. The immediate impacts of flooding include loss of human life, damage to property, destruction of crops, loss of livestock, and deterioration of health conditions owing to waterborne diseases. As communication links and infrastructures such as power plants, roads and bridges are damaged and disrupted, some economic activities may come to a standstill, people are forced to leave their homes and normal life is disrupted.

Answer : The economic impacts of the seaport are classified as:

• Direct impact is the employment and income generated by the direct construction and operation of the port.
• Indirect impact is the employment and income generated by the chain of suppliers of goods and services.
• Induced impact is the employment and income generated by the spending of incomes by employees created by the direct and indirect effects.
• The catalytic impact is the employment and income generated by the role of the port as a driver of productivity growth and then as an attractor of new firms.

Issues related to ports are:

• Inefficient cargo handling and low productivity
• Equipment utilisation is very poor both because equipment is obsolete and poorly maintained.
• Over staffing at Indian ports remains rampant and productivity indicators in respect of cargo and equipment handling con-tinue to be poor.
• Documentary procedures relating to cargo handling such as customs clearance requirements are unduly complicated and time consuming. Electronic document proce-ssing is still to be introduced in all the ports.
• Port access facilities and arrangements for moving inbound and outbound cargo are inadequate and unsatisfactory.
• Absence of inter-port and intra-port compe-tition which have been conductive to substantial productivity increases in other countries is absent in Indian due to poor inland connectivity and a policy regime that protected domestic ports against competitive pressures.

Answer : A tropical cyclone is a rotational low pressure system in tropics when the central pressure falls by 5 to 6 hPa from the surrounding and maximum sustained wind speed reaches 34 knots (about 62 kmph). It is a vast violent whirl of 150 to 800 km, spiraling around a centre and progressing along the surface of the sea at a rate of 300 to 500 km a day.

The tropical cyclones form over ocean basins in lower latitudes of all oceans except south Atlantic and southeast Pacific. The tropical cyclones develop over the warm water of the Bay of Bengal and the Arabian Sea.

Cyclone over Arabian Sea is weak in comp-arison to that of Bay of Bengal because:

• Cyclones that form over the Bay of Bengal are either those develop insitu over southeast Bay of Bengal and adjoining Andaman Sea or remnants of typhoons over Northwest Pacific and move across south China sea to Indian Seas. As the frequency of typhoons over Northwest Pacific is quite high (about 35 % of the global annual average), the Bay of Bengal also gets its increased quota.
• The cyclones over the Arabian Sea either originate insitu over southeast Arabian Sea (which includes Lakshadweep area also) or remnants of cyclones from the Bay of Bengal that move across south peninsula. As the majority of Cyclones over the Bay of Bengal weaken over land after landfall, the frequency of migration into Arabian Sea is low. In addition the Arabian Sea is relatively colder than Bay of Bengal and hence inhibits the formation and intensification of the system.
• High population density, comparatively better employment opportunities and economic compulsions force people to occupy, areas, which are susceptible to cyclones, saline ingress and flooding. Thus damages due to cyclones are high.

Cyclone causes following damages:

Extensive damage to all types Kutcha houses, some damage to old badly managed Pucca structures. Potential threat from flying objects.

• Extensive uprooting of power and communication poles.
• Disruption of rail / road link at several places.
• Extensive damage to standing crops plantations, orchards.
• Blowing down of Palm and Coconut trees.
• Uprooting of large bushy trees.
• Storm surge up to 2 – 5 m, may torn the ships and boats.

Thus frequent cyclones in Bay of Bengal leads to widespread damage to the infrastructure, agriculture, human resource, hence economic development get disrupts in comparison to that of Arabian Sea. Due to cyclonic uncertainty, investment in such areas is also low.

Answer : Primary industry involves the extraction of resources directly from the Earth, this includes farming, mining and logging. They do not process the products at all. They send it off to factories to make a profit. They include:

i)Agriculture: It depends heavily on land and water availability and hence is highly localized. E.g. Punjab plains. Modern technology has made it possible to be practised in difficult and remote areas also.

ii)Fishing: It is extremely localized due to fixed location of fishing banks. Most developed where there is fusion of warm and cold ocean currents. E.g. Great Bank and Grand Bank

iii)Forestry and lumbering: It can be practised only in forested areas and where single species is found in abundance. E.g. Taiga region and Monsoonal forests.

iv)Mining and quarrying: It is practiced only in mineral zones. It includes oil extractions based on geological characteristics of a place thus making it highly localized. E.g. Middle-East, Dharwar region.

Answer : Volcanism is a phenomena associated with the surfacial discharge of molten rock, pyroclastic fragments, or hot water and steam, including volcanoes, geysers, and fumaroles. Sometimes lava appears at the surface of the Earth. At other times, magma does not come to the surface, but stays underground. In both cases, the magma eventually solidifies and the resulting rocks and formations are igneous. The rocks that solidify beneath the ground are called intrusive rocks, while those that solidify above the surface are called extrusive rocks.

Geological significance:

Volcanoes lead to formation of different geographical structures such as:

• Lava domes are formed by viscous magma being erupted effusively onto the surface and then piling up around the vent.
• A lava plateau is caused by a large amount of less viscous lava that flows over a large area. When it solidifies, it creates a large, flat surface of igneous rock. Ex. Deccan Plateau of India.
• The Hawaiian Islands are formed from solidified lava from shield volcanoes that have grown over the last 5 million years.
• When volcanoes erupt, the lava releases some healthy gases, including carbon dioxide and hydrogen. When oxygen mixes with hydrogen, it creates water vapor and that begins the water cycle.
• Batholiths are formed deep below the surface when large masses of magma cool and solidify. As the magma cools slowly, large crystals are formed in the rock (e.g. Granite).

Economic significance:

• Many of the volcanic materials have impo-rtant industrial and chemical uses.
• A natural glass that comes from lava is pumice; it is widely used for grinding and polishing metals, stones, and other materials.
• When lava dries and makes a rock form it is commonly used in building roads. Volcanic ash that has been weathered greatly improves soil fertility.
• Volcanic material has a source of precious gems, Opal.
• Being a tourist attraction, volcanic sites earn foreign currency also, e.g. Geysers in Yellow Stone National Park.
• It also has a source for metals, gold, silver, molybdenum, copper, zinc, lead, and mercury.

Answer : The impacts of offshore drilling on marine environment are:

• Whenever oil is recovered from the ocean floor, other chemicals and toxic substances come up too-things like mercury, lead and arsenic that are often released back into the ocean.
• Seismic waves used to locate oil can harm sea mammals and disorient whales.
• The infrastructure required to drill wells and transport offshore oil can led to erosion and removal of storm buffer.
• Offshore oil rigs may also attract seabirds at night due to their lighting and flaring and because fish aggregate near them. Bird mortality has been associated with physical collisions with the rigs, as well as incineration by the flare and oil from leaks.
• The drilling waste, including metal cuttings, from exploratory drilling are generally dumped in the ocean which disturbs the chemical equilibrium of the ocean.

Answer : Human beings have an enormous impact on the natural environment, it not only affect the long-term availability of those resources but well-functioning Earth systems such as climate systems, hydrological cycles, nutrient cycles in the atmosphere, hydrosphere, and lithosphere, and a diverse biosphere.

• The concept of an ecological footprint estimate how much of the global resources individuals use to sustain their lifestyles.
• Due to unplanned development of cities that result in the enormous increase in per capita energy and material consumption which has been made possible by technology, and universally increasing dependencies on trade, the ecological locations of high-density human settlements no longer coincide with their geographic locations.
• Some initiatives which policy makers can take up: create green networks with green belts; arrest urban sprawl through city zoning; promote low energy housing and efficient public transports; develop private green spaces; green rooftops, community gardens, green walls and put more solar plants; and citizens can try and reduce and recycle the waste generation and water use, build green rooftops, etc. to reduce ecological footprint of the cities.

Answer : Limitation of the theory of Continental drift.

It is clear that Wegener had amassed an imposing array of evidences in support of his theory and some of this evidence was undeniably convincing. But so much of theory was based on speculation and inadequate evidence that it provoked a lot of criticism and controversy.

(a)The greatest criticism has been the force of continental drift proposed by him. He proposed that the tidal force behind the movement of the continents. But for that the tidal force need to be ten thousand million times stronger than at present to move the continents. He was unable to convince the exact cause.

(b)Wegener proposed that Rockies and Andies mountain chain are formed during the westward drift of Americas. But if the SIAL (continents) is floating over SIMA (ocean floor), then the SIMA could not offer so much resistance as to cause folds and build mountain system.

(c)The jig-saw-fit of the opposing coasts of Atlantic Ocean was not so complete.

(d)Though there was similarity in the structural and stratigraphical features of the two coasts of the Atlantic, it would not be quite correct to conclude that one was an extension of the other and that they were joined together.

(e)Wegner has not elaborated the direction and chronological sequence of the displacement of the continent. He did not describe the situation pre carboniferous times.

Plate Tectonic - The term plate was first used by Tuzo Wilson in his definition of transform faults in 1965, but the hypothesis of plate tectonics was first outlined by W.J. Morgan in 1967. It first came to be known by the name of New Global Tectonics but after sometime the term Plate Tectonics gained currency. Basic assumptions of plate tectonics are as follows:

1. There is spreading of sea floor and new oceanic crust is being continually created at the active mid-oceanic ridges and destroyed at trenches.
2. The area of the earth's surface is fixed. It means, the amount of crust consumed almost equals the amount of new crust created.
3. The new crust that is formed becomes part and parcel of a plate.

Movement of Plates: These tectonic plates float on and travel independently over the asthenosphere, which lies over the mantle. Much of the earth's seismic activities occur at the boundaries of these plates. It is a relatively slow movement, driven by thermal convection currents and other geological activities originating deep within the earth's mantle. Plates have moved horizontally over the asthenosphere as rigid units.

The arctic ridge has the slowest rate(less than 2 cm per year), and the East Pacific Rise near Easter Island in the South Pacific has the fastest rate (more than 15 cm per year). The eastern part (Australia) is moving northward at the rate of 5.6 cm per year while the western part (India) is moving only at the rate of 3.7 cm per year due to impediment by Himalayas. This differential movement is resulting in the compression of the plate near its center at Sumatra and a potential division into Indian and Australian Plates. The rate of spreading at the Mid-Atlantic Ridge near Iceland is relatively slow, about 2 cm per year.

Answer : Heat Budget: The average temperature of the earth overall does not change in spite of continuous supply of sun rays. This is possible only when an equal amount of energy is sent back to space by the earth's system. In the way there is balance between incoming solar radiation and outgoing terrestrial radiations. This balance is known as the heat budget of the earth. Figure depicts the heat budget of the planet earth. Consider that the insolation received at the top of the atmosphere is 100 per cent. While passing through the atmosphere some amount of energy is reflected, scattered and absorbed. Only the remaining part reaches the earth surface.

Roughly 35 units are reflected back to space even before reaching the earth's surface. The details of this reflected radiation are as under:

• Reflected from the top of clouds - 27 units
• Reflected by ice-fields on earth - 02 units
• Reflected by the atmosphere - 06 units

The reflected amount of radiation is called the albedo of the earth. The above given radiation does neither heat the atmosphere nor the earth's surface.

The remaining 65 units are absorbed as:

• Absorbed by the atmosphere - 14 units
• Absorbed by the earth - 51 units (Scattered + direct radiation)

Heat Budget: Scattering takes place by gas molecules and dust particles. This takes place in all directions, some of it earthwards and some towards space. In overall, earth receives 51 units of radiation which in turn radiates back in the form of terrestrial radiation. The details of this reflected radiation are as under:

• Radiated to space directly - 17 units
• Radiated to atmosphere - 34 units

The details of 34 units of radiation absorbed by atmosphere from terrestrial radiations are as under.

Heat Budget

• Absorbed directly -06 units
• Absorbed through convection and turbulence - 09 units
• Absorbed through Latent heat of condensation - 19 units

Total units absorbed by the atmosphere are 48 (14 units insolation + 34 units Terrestrial radiation). These are radiated back into space. Thus, the total radiation returning from the earth and the atmosphere respectively is:

• Radiated back by earth - 17 units
• Radiated back by atmosphere - 48 units

Total - 65 units

• These returning 65 units balance the total of 65 units received from the sun. This account of incoming and outgoing radiation always maintains the balance of heat on the surface of the earth. This is termed the heat budget or heat balance of the earth.
• These factors have caused Earth's climate to change many times. Scientists have pieced together a record of Earth's climate, dating back hundreds of thousands of years (and, in some cases, millions or hundreds of millions of years), by analyzing a number of indirect measures of climate such as ice cores, tree rings, glacier lengths, pollen remains, and ocean sediments, and by studying changes in Earth's orbit around the sun.
• This record shows that the climate system varies naturally over a wide range of time scales. In general, climate changes prior to the Industrial Revolution in the 1700s can be explained by natural causes, such as changes in solar energy, volcanic eruptions, and natural changes in greenhouse gas (GHG) concentrations.
• Recent climate changes, however, cannot be explained by natural causes alone. Research indicates that natural causes do not explain most observed warming, especially warming since the mid-20th century. Rather, it is extremely likely that human activities have been the dominant cause of that warming.

Answer : Distribution of Pressure Belts: The horizontal distribution of air pressure across the latitudes is characterized by high or low pressure belts (figure). These pressure belts are:

Equatorial low pressure belt - This belt extends from equator to 100N and 100S latitudes. This belt is thermally produced due to heating by Sun. Due to excessive heating horizontal movement of air is absent here and only vertical currents are experienced in this belt. Therefore, this belt is called doldrums (the zone of calm).

This belt is also known as-Inter Tropical Convergence Zone (ITCZ) because the trade winds flowing from sub tropical high pressure belts converge here.

Sub-tropical high pressure belt - these extend roughly between 250 and 350 latitudes in both the Hemispheres. The existence of these pressure belts is due to the fact that the uprising air of the equatorial region is deflected towards poles due to the earth's rotation. After becoming cold and heavy, it descends in these regions and gets piled up.

This results in high pressure. Calm conditions with feeble and variable winds are found here. In southern hemisphere, this belt is broken by small low-pressure areas in summer over Australia and South Africa. In northern hemisphere, the belt is more discontinuous by the presence of land masses, and high pressure occurs only over the ocean areas as discrete cells; these are termed the Azores and Hawaiian cells in the Atlantic and Pacific areas respectively.

Sub-polar low pressure belt - It extends along 600 latitudes (550-650) in both the hemisphere. These belts are not thermally induced instead the winds coming from the sub-tropics and the Polar Regions converge in this belt and rise upward. The great temperature contrast between the subtropical and the Polar Regions, gives rise to cyclonic storms in this belt.

Polar high pressure belt - Because of low temperature, air compresses and its density increases. Hence, high pressure is found here throughout the year. This is more marked over the land area of the Antarctic continent than over the ocean of the North Pole. In northern hemisphere, high pressure is not centered at the pole, but it extends from Greenland to Islands situated in the northern part of Canada.

Effect of global warming: The trade winds in the Pacific Ocean are weakening as a result of global warming, according to a new study that indicates changes to the region's biology are possible.

Using a combination of real-world observations and computer modeling, researchers conclude that a vast loop of circulating wind over the Pacific Ocean, known as the Walker circulation, has weakened by about 3.5 percent since the mid-1800s. The trade winds are the portion of the Walker circulation that blows across the ocean surface.

The researchers predict another 10 percent decrease by the end of the 21st century. The effect, attributed at least in part to human-induced climate change, could disrupt food chains and reduce the biological productivity of the Pacific Ocean, scientists said.

Answer : Fronts: When two different air masses with distinct properties (temperature, moisture, density, pressure etc.) meet, the boundary zone between them is called a front. These air masses are brought together by converging movements in the general atmospheric circulation. The process of formation of the fronts is known as frontogenesis. The fronts do not mix readily. In fact, they come in contact with one another along sloping boundaries. These sloping boundaries are actually a transition zone across which a sharp contrast in weather condition occurs. The air masses are of vast size covering tens of thousands of square kilometers. Therefore, frontal zones of discontinuity about 15 to 200 kms wide are relatively narrow. So the weather map they are represented by only a thick line.

Types and Stages of front

• Warm Front: When a warmer and lighter air mass moves against an existing cold and dense airmass, it rises over the coldest and denser air mass. This type of front is known as warm front (figure). As the warm air gradually ascends the gently sloping surface of the wedge of cold air lying ahead, it cools. This cooling leads to the cloudy condensation and precipitation. Unlike the cold front, the changes in temperature and wind direction are gradual.
• Cold Front: When a cold and dense airmass forces its way under warm and lighter airmass it makes the warm and lighter airmass to ride over it. This type of front is called cold front. The effect of friction retards the air motion near the ground, while the free air aloft has a higher velocity.

This causes the cold front to become much steeper than the warm front.

• Stationary Front: A stationary front forms when a cold front or warm front stops moving. This happens when two masses of air are pushing against each other but neither is powerful enough to move the other. Winds blowing parallel to the front instead of perpendicular can help it stay in place.
• Occluded Front: Sometimes a cold front follows right behind a warm front. A warm air mass pushes into a colder air mass (the warm front) and then another cold air mass pushes into the warm air mass (the cold front). Because cold fronts move faster, the cold front is likely to overtake the warm front. This is known as an occluded front.
• At an occluded front, the cold air mass from the cold front meets the cool air that was ahead of the warm front. The warm air rises as these air masses come together. Occluded fronts usually form around areas of low atmospheric pressure. The fronts occur in middle latitudes and are characterised by steep gradient in temperature and pressure. They bring abrupt changes in temperature and cause the air to rise to form clouds and cause precipitation.

Answer : One of the main large-scale influences on climate is latitude - Polar region receive less concentrated sunlight than tropical regions. Seasonality arises from the tilt of the earth's rotational axis with respect to its orbit around the sun, most noticeably at higher latitudes. Regional topography, large bodies of water, and the heat contributed by cities also affect temperature.

Effect of Latitude: Temperature is highly dependent on the amount of solar energy reaching the earth's surface. Because of the curvature of the earth, solar energy reaching high latitude regions passes through atmosphere so more of it is scattered and reflected. Furthermore, the remaining solar radiation arrives at a lower angle, spreading its energy out over a larger area. As a result, regions at high latitudes receive much less solar energy per unit area, and have lower average temperatures than regions closer to the equator.

As the earth revolves around the sun, different regions of the earth are tilted towards and away from the sun because the earth's rotational axis is tilted at 23.5º with respect to the plane of its orbit. As the angle of sunlight varies over time, its warming effect varies also, just as with latitude, though the seasonal variation is exaggerated by the corresponding variation in the length of day. Winter occurs when a region is tilted away from the sun, while summer occurs when a region is tilted toward the sun. Equatorial regions experience only small seasonal changes in temperature due to the relatively constant angle between these regions and the sun.

Other Effect: In coastal regions, temperature is also affected by the ocean - air masses can be warmed or cooled by contact with ocean currents before moving over the land. Also, because water warms and cools more slowly than land, nearness to the ocean or a large lake tends to moderate the daily temperature range - the difference between the daily maximum and minimum temperatures. The diurnal range in temperature increases with distance from the ocean or large lakes, and is highest in continental interiors.

Regional topography has its effect as well: temperatures decrease by about 0.65° with every 100 m gain in elevation, so mountainous regions will be cooler than low-lying regions, if all other factors are similar. Altitude can also affect temperature through exposure to solar radiation and influence on cloud cover.

Urbanization replaces natural components of the landscape with artificial surfaces and structures, differing in colour and material from the natural surface. These changes alter natural processes that affect temperature, including absorption and reflection of solar radiation, evaporation, and the movement of air and moisture. For example, dark surfaces (such as paved roads) absorb heat, while removal of vegetation can reduce both shade and cooling through evapotranspiration. The result is an urban heat island - an area several degrees warmer than surrounding rural areas.

Answer : Climate has a big effect as:

• Food we eat
• Energy we use
• Homes we live in
• Work we do
• Way we spend our free time
• Our culture & heritage

Climatic condition determines state of natural environment in relation to land, soil, water, flora & fauna etc. Natural state of environment creates foundation for human livelihood practices. Livelihood practices leads to the formation of different social groups and traits of belief, values, knowledge system and norms. These together structure the society and form the cultural system at large & mould human way of life.

In many cases the social & cultural practices develop specific knowledge system through its activities which people of this societal group try to assess the weather and predicting its nature traditionally to plan their day-to-day activities.

Answer : The periodical rise and fall of the sea level, once or twice a day, mainly due to the attraction of sun and the moon, is called a tide. Movement of water caused by meteorological effects (winds and atmospheric pressure changes) is called surges. Surges are not regular like tides. The study of tides is very complex, spatially and temporally, as it has great variations in frequency, magnitude and height. The moon's gravitational pull to a great extent and to a lesser extent the sun's gravitational pull, are the major causes for the occurrence of tides. Another factor is centrifugal force, which is the force that acts to counterbalance the gravity. Together, the gravitational pull and the centrifugal force are responsible for creating the two major tidal bulges on the earth.

Types of Tides: Tides vary in their frequency, direction and movement from place to place and also from time to time. Tides may be grouped into various types based on their frequency of occurrence in one day or based on their height.

1.Semi-diurnal tide: The most common tidal pattern, featuring two high tides and two low tides each day. The successive high or low tides are approximately of the same height.

2.Diurnal tide: There is only one high tide and one low tide during each day. The successive high or low tides are approximately of the same height.

3.Mixed tide: Tides having variations in height are known as mixed tides. These tides generally occur along the west coast of North America and on many islands of the Pacific Ocean.

Ebb: The difference between the high tide water and the low tide water is called the tidal range. The time between the high tide and low tide, when the water level is falling, is called the ebb. The time between the low tide and high tide, when the tide is rising, is called the flow or flood.

Once in a month, when the moon's orbit is closest to the earth (perigee), unusually high and low tides occur. During this time the tidal range is greater than normal. Two weeks later, when the moon is farthest from earth (apogee), the moon's gravitation force is limited and the tidal ranges are less than their average heights. When the earth is closest to the sun (perihelion), around 3rd January each year, tidal ranges is also much greater, with unusually high and unusually low tides. When the earth is farthest from the sun (aphelion), around 4th July each year, tidal ranges are much less than average.

Effects of Tide

• Tidal flows are of great importance in navigation. Tidal heights are very important, especially harbours near rivers and within estuaries having shallow 'bars' at the entrance, which prevent ships and boats from entering into the harbour. Large ships enter the harbour of a shallow sea during high tide and they go back also at the time of high tide. London and I have become important ports due to the tidal nature of the mouths of the Thames and Hugli rivers respectively.
• The river mouths and estuaries are kept clean of sedimentation due to the action of tidal currents. The force of the outgoing tide and the river current carries the silt away to the open sea. This helps in navigation.
• The tidal force can also be used as a source for generating electricity. A 3 MW tidal power project at Durgaduani in Sunderbans of West Bengal is under way.
• The inflow of the salty tidal water, especially along the coast of cold countries, retards the process of freezing and prevents the harbours from becoming ice-bound.
• The fishing industry is helped by the rhythm of high and low tides. The fishermen mostly sail out to the open sea during low tides and return to the coast at high tides.

Answer : It is the removal of soil at a greater rate than its replacement by natural agencies. Soil forming and erosional processes go on simultaneously. When the balance between these two different processes is disturbed by natural or human factors, result into net removal of soil. Some soil erosion occurs without the intervention of human activities but the latter often accelerates the natural processes, e.g. vegetation clearance, over-grazing, some land-drainage schemes. Problem of soil erosion increases with pressure of increasing population on the land. Natural vegetation is cleared for agricultural, pastoral and construction activities.

Topography, rainfall, wind, lack of vegetation cover, land use practices etc. are the causes of soil erosion. The rugged topography and steep slopes affect soil erosion rate through its morphological characteristics. Two of these, namely gradient and slope length, are essential components in quantitative relationships for estimating soil loss. Erosion increases dramatically because the increased angle facilitates water flow and soil movement.

• Soil Conservation: Soil conservation is not a single and straight process. It concerns all operations, practices that are used to maintain the quality of soil. Soil erosion is essentially aggravated by faulty practices. For instance, recommended ratio of nitrogen, phosphorus and potassium (NPK) fertilizer in India is 4:2:1 but actual usage is in the ration of 10:4:1. Lands with a slope gradient of 15 - 25 per cent should not be used for cultivation. If at all the land is to be used for agriculture, terraces should carefully be made. Over-grazing and shifting cultivation should be regulated and controlled by villagers collectively. Contour bunding, Contour terracing, check dams, regulated forestry, cover cropping, mixed farming and crop rotation are some other sustainable methods to manage soil quality. In arid and semi-arid areas, shelter belts or green belts should be constructed around the cultivable land to protect them from progressive sand dunes.
• Effect of Soil Health card on Erosion Control: Under the scheme the government plans to issue Soil card to farmers which will carry crop-wise recommendations of nutrients and fertilizers required for the individual farms to help farmers to improve productivity through judicious use of inputs. All soil samples are be tested in various soil testing labs across the country. Thereafter the experts will analyse the strength and weaknesses (micro-nutrients deficiency) of the soil and suggest measures to deal with it. The result and suggestion will be displayed in the cards. This benefit may help to improve the quality of soil which would help to reduce soil erosion.

Answer : Agro forestry or Agro-sylviculture is a land use management system in which trees or shrubs are grown around or among crops or pastureland. It combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy, and sustainable land-use systems.

Types of Agro Forestry: There are different types of agro forestry which are characterized on the basis of their growth or combination with forestry. There are four different types of agro forestry which manages the land and also enhance the productivity, these types are as follows

1. Silvopasture agro forestry
2. Silvoarable agro forestry
3. Forest forming
4. Forest gardening

Silvopasture Agro Forestry: A type of agro forestry which came into being by the combination of trees and plants such as forest and the animals that feed on the grass is called as Silvopasture agro forestry. These animals are commonly called as domesticated animals. This type of agro forestry helps in reducing the soil erosion and also support in producing the products and environment for the long time.

Silvoarable Agro Forestry: A type of agro forestry which is formed as a result of combining the forest land and the different type of cultivating crops is called as Silvoarable agro forestry. It really helps us to produce the new variety of different types of plants and horticultural crops.

Forest Farming: The type of forestry in which different types of cultivated plants are used to cultivate in the area of forest is called as forest farming. As we know that the amount of rain fall in the forest is higher as compared to other lands or area so, the soil of the forest is much fertile then other farms so it is quite easy to develop the farm there.

Forest Gardening: The branch of agro forestry which is used to manage the replacement of wild plants with the cultivated plants such as fruit plants, vegetables, herbs, shrubs etc is referred as forest gardening. It is a very useful branch of agro forestry for human beings

Biodiversity in Agro-Forestry systems is typically higher than in conventional agricultural systems. With two or more interacting plant species in a given land area, it creates a more complex habitat that can support a wider variety of birds, insects, and other animals.

Application and benefit of Agro Forestry:

• Reducing poverty through increased production of wood and other tree products for home consumption and sale
• Contributing to food security by restoring the soil fertility for food crops
• Cleaner water through reduced nutrient and soil runoff
• Countering global warming and the risk of hunger by increasing the number of drought-resistant trees and the subsequent production of fruits, nuts and edible oils
• Reducing deforestation and pressure on woodlands by providing farm-grown fuel wood
• Reducing or eliminating the need for toxic chemicals (insecticides, herbicides, etc.)
• In situations where people have limited access to mainstream medicines, providing growing space for medicinal plants
• Increased crop stability

Answer : The oceans current are horizontal flow of a mass of waters in a fairly defined direction over great distances. They are like stream of water flowing through the main body of the ocean in a regular pattern. The average speed of current is between 3.2 km to 10 kms per hour.

• Oceans currents closely influence the distribution of temperature, pressure, winds and precipitation, which directly or indirectly influence the economy and society of the people, especially those living in the coastal regions. Some of the important effects of oceans currents are as follows:
• Currents move from warm temperature areas to colder temperature areas and vice versa. As they move from one place to another they partly attempt to modify the temperature. The temperature of a mass of water affects the temperature of the air above it. Therefore, the ocean current that moves from the equatorial region to the colder latitudes raises the temperature of the air in the areas into which it moves. For example, warm North Atlantic Drift which flows northwards to West European coast helps to keep the coast of Great Britain and Norway free of ice in winter too. The effect of the ocean current becomes clearer after comparing the winter conditions of the British Isles with that of the North East Coast of Canada situated on the same latitudes. Since the North East Coast of Canada comes under the influence of cold Labrador Current, it remains ice bound during the winter time.
• When cold and warm currents meet they produce mist and fog. For example, near New Foundland warm Gulf Stream meets Labrador Current and produces fog. They also create conditions for storms. Hurricanes in New Found land and Typhoons in Japan are perhaps the result of the meeting of warm and cold currents.
• Warm ocean currents greatly influence the climate of the land they pass by in several ways. Warm currents lead to warm weather conditions because the air above water is also warm. This warm air passes over the land and keeps the average temperatures higher than other places at the same latitude. The Gulf Stream raises the temperatures of coastal Europe. Another effect is of warm currents is heavy rainfall along the coastal lands. Warm temperatures evaporate the water and moist air blows over land where it cools and falls as rain. This is especially true in India.
• Cold currents bring cold water and cold air above it. In fact, land that touches cold water currents will often have a desert such as the Sahara in Africa or in Australia where 18% of the land is desert.

Answer : A river delta is a landform that forms at the mouth of a river, where the river flows into an ocean, sea, estuary, lake, or reservoir. Deltas form from deposition of sediment carried by a river as the flow leaves its mouth.

Factors influencing formation of deltas:

1. Amount and type of sediment available.
2. Variations in volume of water discharged from river.
3. Aspect and geometry of coast.
4. Coastal processes in operation, for example, wave action.
5. Changes in coast level.
6. Impacts of climate on growth of vegetation and marine organisms.

Human activities, including diversion of water and the creation of dams for hydroelectric power or to create reservoirs can radically alter delta ecosystems. Dams block sedimentation, which can cause the delta to erode away. The use of water upstream can greatly increase salinity levels as less fresh water flows to meet the salty ocean water.

It is being recognized that no legal provisions can be effective unless local communities are involved in planning, management and moni-toring conservation programmes.

The steps needed are:

• Work with communities on safer environment via wetland restoration.
• Develop and share our practical experience and knowledge on the role that specific wetlands play in mitigating water related extremes.
• Advocate to governments, development organisations and finance institutions to support wetland conservation, wise use and restoration.
• There is a need to collaborate with hum-anitarian organisations and other decision-makers to integrate ecosystem and landscape based approaches into their disaster risk efforts.

Answer : Fishing is central to the livelihood and food security of 200 million people, especially in the developing world, while one of five people on this planet depends on fish as the primary source of protein. According to UN agencies, aquaculture - the farming and stocking of aquatic organisms including fish, molluscs, crustaceans and aquatic plants - is growing more rapidly than all other animal food producing sectors.

Fishing resources: The most productive fishing area of the world is the northwest Pacific Ocean. In this area all the major groups of fish species are represented in more or less equal share. The second most productive area is the southeast Pacific, where catches are dominated by small pelagic fish species (mostly Peruvian anchoveta). In the northeast Atlantic Ocean, the third most productive area, demersal (bottom) fishes are the most abundant, followed by larger pelagic and small pelagic species. In the fourth most productive area of the world, the western Central Pacific, the catches are dominated by larger pelagic species. The larger pelagic species are also the most abundant group in the western Indian Ocean.

Measures to optimize its potential

• Building adaptive capacity to climate change in fisheries and aquaculture
• Strengthening gender equality in fish-dependent communities
• Increasing the benefits to poor people from fisheries and aquaculture value-chains
• Improving nutrition and health through fisheries and aquaculture
• Identifying and promoting policies and practices to increase the resilience of small-scale fisheries
• Sustainably increasing the productivity of small-scale aquaculture

Answer : The drainage systems in India can be divided into two major groups, viz. the Himalayan Rivers and the Peninsular Rivers. Most of the Himalayan Rivers are perennial, i.e. they have water throughout the year, and on the other hand Peninsular Rivers are seasonal because they depend on rainfall for water. These rivers have shorter and shallower courses; compared to the Himalayan rivers.

• The Peninsular drainage system is older than the Himalayan one. This is evident from the broad, largely-graded shallow valleys, and the maturity of the rivers. The Western Ghats running close to the western coast act as the water divide between the major Peninsular Rivers, discharging their water in the Bay of Bengal and as small rivulets joining the Arabian Sea. Most of the major Peninsular Rivers except Narmada and Tapi flow from west to east. The Chambal, the Sind, the Betwa, the Ken, the Son, originating in the northern part of the Peninsula belong to the Ganga river system.
• Peninsular rivers are characterized by fixed course, absence of meanders and non-perennial flow of water. The Narmada and the Tapi which flow through the rift valley are, however, exceptions.
• On the other hands Himalayans Rivers are perennial; receive water from glacier and rainfall and have very large basins. These rivers are Young and youthful, active and deepening in the valleys.
• They are antecedent and consequent leading to dendritic pattern in plains. These rivers have long course, flowing through the rugged mountains experiencing headward erosion and river capturing. In plains they formed meandering and shifting of course.

Answer : A slum can be defined as a “compact settlement with a collection of poorly built tenements, mostly of temporary nature, crowded together usually with inadequate sanitary and drinking water facilities in unhygienic conditions.” The growth of metropolitan cities in India has been largely unplanned and haphazard and this can be seen from the fact that one-fourth of total urban population lives in slum and squaller settlements.

• The rapid urbanization in conjunction with industrialization and lack of infrastructural and employment opportunities in rural areas has led to mass rural-urban migration and this has resulted in the growth of slums.
• The proliferation of slums occurs due to many factors such as the shortage of developed land for housing. The high prices of land are beyond the reach of urban poor.
• Poor housing settlement: All slums and squatters are made of bamboo, straw, low quality wood and tin and plastic sheets. Population density in slums and squatters ranges from 700 to 4210 per acre and a minimum of four and maximum of ten people share a room, which is highly congested and unhealthy. This poor housing and lifestyle cause a number of problems for the environment of city like indoor pollution, degradation of air quality with frequent slum fires, increase incidence of communicable disease that may spread to city dwellers from the workplace.
• Lack of water supply and sanitation facility: They lacks safe drinking water and proper sewerage services. As a result, both household waste and human generated wastes go directly or indirectly into the low-lying lands, open spaces or water bodies of the city and causes a number of problems.
• Crime and Other Social Problems: It socially slums tend to be isolated from the rest of the urban society, characterized by urban decay, high rates of poverty, illiteracy and unemployment, slums are commonly seen as “breeding grounds” for various social problems such as crime, drug abuse and alcoholism.

Answer : A low-lying relatively flat or slightly rolling land surface with very gentle slope and minimum local relief is called a plain. The plains can be classified into the following types:

(a) Structural plains: These plains are mainly formed by the uplift of a part of the sea-floor or continental shelf. These are located on the borders of almost all the major continents. The south eastern plain of the United States formed by the uplift of a part of the Gulf of Mexico is an example of this type of plain. The structural plains may also be formed by the subsidence of areas. One such plain is the central low-lands of Australia.

(b) Erosional Plains: These plains are formed by the continuous and a long time erosion of all sorts of upland. The surface of such plains is hardly smooth. These are therefore also called peneplains which mean almost a plain. The Canadian shield and the West Siberian plain are examples of erosional plains.

(c) Depositional plains: Fragments of soil, regolith, and bedrock that are removed from the parent rock mass are transported and deposited elsewhere to make on entirely different set of surface features–the depositional landforms. When plains are formed by river deposits, they are called riverine or alluvial plains. The Indo Gangetic plain of the Indian sub-continent, the Hwang-Ho Plain of North China, the Lombardy Plain of the Po River in Italy and the Ganga-Brahmaputra Delta Plain in Bangladesh are examples of alluvial plains.

The deposition of sediments in a lake gives rise to a lacustrine plain or a lake plain. The Valley of Kashmir and that of Manipur are examples of two most prominent lacustrine plains in India. When plains are formed by glacial deposits they are called glacial or drift plains. Plains of Canada and North-Western Europe are examples of glacial plains. When wind is the major agent of deposition, they are called loess plains. Loess plains of North- Western China are formed by the deposits of loess air- borne fine dust particles.

Plains are useful for mankind because:

1. Fertile Soil: The plains generally have deep and fertile soil. Since the plains have a flat surface, the means of irrigation are easily developed. Both these factors have made the plains agriculturally so important that they are often called ‘food baskets of the world’.
2. Growth of Industries: The rich agricultural resources especially of alluvial plains have helped in the growth of agro-based industries. This has given employment to millions of people and has registered a marked increase in the national production and per capita income. Since the plains are thickly populated, plenty of labour is available for the intensive cultivation and for supplying work force for industries.
3. Expansion of Means of Transport: Since the plains have an even surface it favours the building of roads, airports and laying down of railway lines.
4. Centres of civilization: The plains have been the centres of many modern and ancient civilizations. The major river valley civilizations of the world have flourished in the plains only. Hence, they are aptly referred to as the cradles of civilization. For example, there are the civilization of the Indus and the Nile Valley.
5. Setting-up of Cities and Town: Easy means of transport on land, the growth of agriculture and industries in plains have resulted in the setting-up and expansion of cities and towns. The most developed trade-centres and ports of the world are found in the plains only. Rome, Tokyo, Calcutta, Yangoon (Rangoon), Varanasi, Paris and other famous cities are situated in the plains. As much as 80% of the world’s population lives in the plains.

Answer : Plate tectonics, like crustal evolution, provide a basis for understanding the distri-bution and origin of mineral and energy deposits. The relationship of plate tectonics and mineral deposits is significant on three counts:

1. Geological processes operating due to energy released at plate boundaries control the process of mineral deposition.
2. Mineral deposits form in particular tectonic settings which are governed by plate tectonics.
3. Reconstruction of fragmented continents can provide a useful basis for explor-ation of new mineral deposits.

Because different types of mineral deposits form in different environments, plate tectonics plays a critical role in the location of different geological environments. The linkage has been described as follows:

Different kinds of plate boundaries can involve these ways of concentrating elements and minerals.

I. Diverging boundaries: At the mid-ocean ridges, ocean water percolates through cracks in the ocean floor.It runs through hot young igneous rock and dissolves out minerals.It also combines with left-over water from magma crystallization, which is already rich in metals.Some of this water percolates through cracks in the rock, and the metals are concentrated in new minerals.In other places the hot water spews out of vents on the ocean floor.The metals form a cloud of dark particles, so we call these hot water vents “black smokers”. The metal rich particles land all around the black smoker.Most of the metals are combined with sulphur in minerals such as pyrite (iron sulphide) and galena (lead sulphide).Bacteria that eat sulphur grow all around the black smokers, and entire ecological communities of worms, crabs and clams develop based on these sulphur-eating bacteria.

Wherever diverging boundaries have been in the past, the metal-rich rocks are left behind.So we can look for metal ores at both modern diverging boundaries that are still operating, and at ancient ones that are not currently producing new ocean floor.

II. Subduction zone: Subduction zones are home to many volcanoes.At these volcanoes, hot water percolates through the volcanic rock, heats up and carries dissolved minerals into surrounding rocks.More than half of the world’s copper comes from this kind of deposit.When magma within the volcanoes cools and crystallizes, pegmatite and mineral veins form.The Mother Lode of the Sierra Nevada is an example of gold deposits in mineral veins formed from left-over fluids from magma.In Brazil, many of these kinds of mineral veins carry spectacular emeralds.When the volcanic mountains of the subduction zone erode, chunks of gold, silver or metal may be relesed into the streams where they accumulate as placer deposits.So subduction zone mountains are good places for both hard-rock mines, where miners burrow into the ground to find minerals, and for placer miners, who sift through the river sediment to find metals ands gems.

III. Convergent regions: When two continents collide, or when an island chain runs into a subduction zone, the incoming landmass may carry some concentrations of minerals that were formed at diverging boundaries or at subduction zones.So zones of collision can have any of the kids of mineral deposits described above, as well as minerals formed as the rocks metamorphose due to great pressure.Sometimes bits of ocean floor are trapped between the landmasses during the collision.These slices of ocean floor often carry asbestos, a mineral form used in many industries.Because the collision zones contain the remnants of other kinds of plate boundaries and even some ocean floor, they have the most varied opportunities for finding mineral resources.

Answer : Generally resource rich regions of the world have been imperial colonies earlier thus making them development deficient. However, there are exceptions like resource rich regions of Canada, USA, Australia, Russia etc. which have managed to develop well after imperial era.

• Phenomenon of resource curse- The resource curse (Paradox of Plenty) refers to the paradox that countries and regions with an abundance of natural resources, specifically point-source non-renewable resources like minerals and fuels, tend to have less economic growth and worse development outcomes than countries with fewer natural resources. The “resource curse” in development is well known. Countries endowed with valuable natural resources –most notably oil, natural gas, minerals, and diamonds – often also suffer from poor governance, high poverty, and conflict. And, as recent events in the Middle East have reminded us, such countries are frequently authoritarian and highly repressive.
• Although half of the remaining forests in mainland Southeast Asia are in Burma, Burma has the lowest per capita GDP in Southeast Asia.The mix of resource abundance and poor governance is especially lethal in resource-rich Africa- For example, the Republic of Congo and Equatorial Guinea, with a government widely seen as autocratic, has the worst control of corruption score among African countries.
• Often countries with weak governance and abundant natural resources are prone to armed violence. For example, Sudan, where oil rents are equal to more than 18% of gross domestic product (GDP), and Nigeria, where oil rents amount to almost 30% of GDP, Afghanistanwith huge copper and iron ore desposits have been plagued by conflict.
• Resource-rich countries are plagued by a phenomenon called "Dutch disease". (The Economist coined the term in 1977 to describe the impact of the North Sea gas bonanza on the economy of the Netherlands, whose exports of natural resources led to foreign exchange inflows which drove up the value of the currency. The overvalued currency made domestic manufacturing, agriculture, and other exports less competitive.) This illness afflicts both well-governed and poorly-governed countries, but the former have more ways of allaying the consequences.
• Corruption is endemic in many of Asia and Africa's most resource-rich countries. Rather than invest resource revenues into infrastructure and education, crooked politicians, often in collusion with the companies mining the resources, siphon proceeds from the continent's mineral and petroleum wealth into their own pockets. For example – Afghanistan, Iraq, Ethopia etc.
• Lack of public pressure and accountability due to low level of education and institutional development. Also overall human development is very poor. Lack of infrastructure and skills, led to dependence on foreign power and MNCs for development of natural resources. Exp- issue of land grab in Africa by MNCs for agricultural development has led to more displacement and less food security.
• Geopolitical and economic consideration often led to, political competition over rents in resource-dependent countries. Bilateral donors, multilateral financial institutions, industry, private financial institutions, and civil society have made promising steps towards addressing the resource curse in recent years. For example, the World Bank's International Finance Corporation (IFC) stipulates the social, environmental, and governance requirements for all World Bank investments in private-sector projects. In 2011, the IFC made revisions that included strong improvements mandating contract and revenue transparency.

Answer : The forces, which the affect crust of the earth, are divided into two broad categories on the basis of their sources of origin, they are Endogenetic Forces and Exogenetic Forces.

The Endogenetic Forces (Diastroph forces, volcanic eruption, Earthquak etc.) give rise to several vertical irregularities, which leads to the formation of numerous varieties of relief features on the earth surface (e.g. Plateau, mountain, plain, lakes, faults, folds etc). Mid oceanic ridges are caused by continuous over flow of Magma from beneath the earth surface.

Compressional Forces and Tensional Forces: Due to compressional forces, the rock strata gets folded. For example Folded Mountain Himalayas, Volcanic archipelago like Japan. Faults are formed due to the combined effect of both the compressional and tensional forces. Rift valley are actually formed due to displacement of crustal parts and subsidence of middle portion between two normal faults. The Dead Sea of Jordan is located in a Rift valley. When the middle portion remains at place and the two side blocks move downwards, the Block Mountains are formed. Satpura mountains in India, Black Forest and Vosages in Germany.

Exogenetic Forces: The main function of the exogenetic forces on the surface of the earth is denudation which includes, the processes of weathering and erosion.

Weathering: The process of disintegration and decomposition of rocks, due to physical, chemical or biological factors, at their own place is known as weathering. Based on the causes, the process of weathering is classified into three types:

A.Physical or Mechanical Weathering (Due to insolation (Temperature), Due to Frost action, Due to Friction, Due to Pressure, Exfoliation)

B.Chemical Weathering (By oxidation, By Carbonation, By Hydration, Chelation, Hydrolysis)

C.Biological Weathering (By Plants, By Animals, Due to Human Activities (Anthropo Weathering).

Erosion: Large scale transportation of the weathered materials is termed as erosion.

A.Running Water (River): The area drained by a river and its tributaries known as River Basin Catchment Area. Differ landforms by a river are: v-shaped valley, waterfalls and rapids, alluvial cones, alluvial fans, ox-bow lakes, deltas etc.

B.Wind: The wind is the most active agent of gradation in the arid and semi-arid regions where rainfall is very scanty and the ground surface is covered with loose particle of soil in the absence of both moisture and vegetation cover. For example- Mushroom-Rock, sand dunes, playa etc.

C.Sea Water: Seawater carves different landforms with the help of sea-waves, currents, tidal waves or tsunamis. For examples- Coastal Cliffs, caves, stacks, beach, lagoon etc.

D.Glaciers: The moving ice mass down slope under the impact of gravity is called glacier. Snow line is generally defined as a zone between permanent and seasonal snow. They formed on high mountains are long and narrow because they are formed in an abandoned river valley. Different landforms carved out by glaciers are: U-shaped Valley, Hanging valley, Horns. Etc.

Answer : Climate and soil are the major factors influencing plant growth. The soil provides the physical conditions for root development and anchorage and supplies the inorganic nutrients and moisture required by the plant. With the advent of modern agricultural technology there is a continuous surge for diversified agriculture in terms of crops, primarily on economic conside-rations. This leads to commercialization of agricu-lture thus lead to disastrous consequences. This can be discussed using the example of green revo-lution in India.

Green Revolution consequences:

• Led to increment in yields of rice and wheat.
• Higher yields and profitability also led farmers to increase the area of rice and wheat they grew at the expense of other crops.
• HYV seeds need more water and fertilizer, which is expensive. Poor farmers could not afford HYV seeds, fertilizers and machinery. Some borrowed and ended up with large debts.
• New machinery replaced manual labour leading to unemployment and rural-urban migration.
• Green Revolution resulted in environmental degradation. Excessive and inappropriate use of fertilizers and pesticides has polluted waterways, poisoned agricultural workers, and killed beneficial insects and other wildlife. Irrigation practices have led to salt build-up and eventual abandonment of some of the best farming lands. Groundwater levels are retreating in areas where more water is being pumped for irrigation than can be replenished by the rains. And heavy dependence on a few major cereal varieties has led to loss of biodiversity on farms.
• It increased income inequality, inequitable asset distribution, and worsened absolute poverty.
• Shift towards water intensive crops has led to extremely low agricultural output in Maharashtra. This became a major cause of farmers' suicides.

Answer : Geopolitics is about how the world is understood politically at the planetary scale. It is simultaneously a term that refers to great power rivalries and the knowledge and representational practices that legitimate that mode of rule. Now in the face of climate change the premises for thinking about human politics have been dramatically changed, even if many political elites and scholars have yet to face up to the changed circumstances for geopolitical thinking and practical matters of ruling a biosphere that is being transformed by human action. Where geopolitics in the past provided the context for thinking about human actions, in coming decades the political decisions that are made will shape that human context fundamentally. Anthropocene thinking changes the parameters of geopolitics, but it remains to be seen whether institutions capable of making intelligent decisions about such matters as whether the planet will have polar ice caps in coming centuries will emerge in the coming decades.

In the first decade of the twenty first century humanity became an urban species. Now for the first time the majority of a still rapidly growing population live in towns and have to be fed and supplied with the necessities of life there, frequently at great distance from the sources of supplies of food, fuel and fiber that are needed. New techological systems provide many of the key items that make urban lives possible and these systems require very different logistics from the rural, agricultural, and land based economies of the recent past. The transformation of human affairs by the extraordinary growth in industrial production and the speed of technological innovation need to be emphasised. So too does the changing pattern of international rivalries, the patterns of militarism, the propensities for warfare, and arenas of conflict.

Globalization is about this transformation of the human condition much more than it is about the apparently novel trans-boundary migration of people and products. In some ways the phenomena labled globalization are an artifact of the methodologies used by governments and scholars for tabulating and measuring things. Statistics are a matter of states usually, and this methodological nationalism is all too often replicated by scholarly investigations working with information in the forms that it is available, and often for the interests of those states too, than looking at the larger patterns. While there may be much larger amounts of trade internationally and much larger quantities of electronic transactions than in the middle of the twentieth century, it is also worth noting that there are now more than three times the number of states than there was when the United Nations came into being in the aftermath of World War Two.

War preparation has morphed once again, this time from the large conscript armies of the centuries following the Napoleonic levee en masse, back to smaller professional armies relying on highly trained cadres, not the mass firepower of industrial production. The emergence of these professional high-technology militaries is combined with the relative decline in importance of territory to the accumulation of wealth, with notable exceptions relating to the sources for some mineral resources and of course petroleum. The potential for interstate warfare, where territory has so frequently been a cause of war (Vasquez 1993), thus seem to be declining notably of late. Coupled with the emergence of the United Nations framework of the territorial covenant and the stable borders norm as a key part of global governance arrangements, great power wars of territorial acquisition seem to be becoming part of the past, even if some lesser powers have yet to take this norm so seriously.

Answer : The forest report 2014 reveals that the total forest & tree cover of India is 24% with Madhya Pradesh leading in terms of area while Arunachal Pradesh leading in terms of percentage.

The forest policy of India gives ample importance to the conservation, security and develo-pment of forest areas. Thus, a target of bringing 33% of the total land area under forest has been fixed. According to it, 20% of the plain areas and 60% of the mountainous region should be under forest cover. In the Tenth Five Year plans a target bringing 25% of total land area under forest by 2007 and 33% of the total land area by 2012 was fixed. But, the efforts in this direct are still not sufficient.

Thus, in order to increase the forest area and the green cover, the government should incentivize the states which are contributing in excess of their total area under forestry.

It will be a laudable step and contribute in the following ways:-

• It will create a sense of responsibility, contribution and healthy competition among the states.
• Such types of royalties being given could be better utilized in sustainable development work, research and conservation activities.
• It will also help in creating awareness among the local people such as the tribals. So that they can also contribute effectively in maintaining the forest cover.
• This type of fund could also be utilized for generating alternate sources/other natural resources such as natural gas, solar energy, tidal energy etc. so as to decrease the burdens on the forest cover.

Answer : India’s 7,500 km long coastline is dotted with some 200 ports, of which twelve are classified as major ports, falling under the juris-diction of the Government of India, while the rest come under individual state governments. Given the importance of ports in a growing economy, the Government of India anticipates that maritime cargo will grow at an average of 11 percent a year until 2020. The sector, however, faces numerous challenges. It needs to meet growing demand as well as compete with the larger and more efficient ports in the region - such as Colombo, Singapore, Port Rashid/Jebel Ali, Khor-Fakkan and Salalah. To realize their full potential, India’s ports will need to be equipped to handle larger vessels, improve their transport linkages with the hinterland, increase private sector participation in their operations, upgrade their governance structures, and introduce an efficient legal and regulatory framework.

• India has approximately 5,700 km of inland waterways - rivers and canals - consisting of a number of water systems that are navigable by mechanized barges. Of this, about 4,700 km constitute India’s National Waterway system (National Waterways 1 to 6) managed by the Inland Waterways Authority of India (IWAI).
• While in some EU countries, inland water-ways handle up to 40% of inland freight, India’s waterways handle less than 0.5% of the country’s inland cargo. Although India’s waterways remain largely undeveloped, they have tremendous potential to grow their share many times over if large modern vessels are able to navigate them throughout the year.
• Global experience indicates that inland waterways are safe, fuel-efficient, cost-effective and environment- friendly when operated efficiently with large modern vessels. This gives them an advantage over other modes of transport, especially over the railways that carry most of India’s bulk freight.
• However, infrastructure and systems on most of India’s national waterways - shipping channels, locks and sluices, navigation aids, loading and unloading points, as well as river training and regulation - are weak. Specific waterway also need to be made attractive for transporting one or two key commodities, such as minerals or food grains, and an enabling business climate needs to be created to encourage a shift to this mode of transport.
• World Bank Support: Since 2013, the World Bank has been working with the Inland Waterways Authority of India to develop potential investments, improve navigability, and increase market share along waterway that have the largest potential – such as NW 1 (Ganges), NW 2 (Brahmaputra) and NW 5 (Brahmani river in Orissa). Given the sector’s huge potential, the Bank’s engagement with inland waterways in India is likely to mature further.

Answer : Climate change is inevitable and unstoppable in its nature. However, the 20th century global warming has been linked directly with anthropological impacts, such as the burning of fossil fuel, excessive emission of greenhouse gases, and urbanization. Climate variability is concerned with the changeability in ‘the mean state and other statistics (such as the standard deviation, extremes, or shape of frequency distribution) of climate elements on all spatial and temporal scales beyond those of individual weather events. Climate change on the other hand is variability that continues over a longer period and is statistically significant.

• Global warming and climate change is one of the most extensively researched and discussed topical issues affecting the environment. Although there are enough historical evidence to support the theory that climate change is a natural phenomenon, many research scientists are widely in agreement that the increase in temperature in the 20th century is anthropologically related. The associated effects are the variability of rainfall and cyclonic patterns that are being observed globally. In Southeast Asia the link between global warming and the seasonal atmospheric flow during the monsoon seasons shows varying degree of fuzziness. The comparison of decadal variation of precipitation and temperature anomalies before the 1970s found general increases which were mostly varying. But beyond the 1970s, global precipitation anomalous showed increases that almost corresponded with incr-eases in global temperature anomalies for the same period. There are frequent changes and a shift westward of the Indian summer monsoon. Alth-ough precipitation is observed to be 70% below normal levels, in some areas the topography affects the intensity of rainfall. These shifting phenomenon of other monsoon season in the region are impacting on the variability of rainfall and the onset of monsoons in Southeast Asia and is predicted to delay for 15 days the onset of the monsoon in the future. The variability of monsoon rainfall in the SEA region is observed to be decadal and the frequency and intensity of intermittent flooding of some areas during the monsoon season have serious consequences on the human, financial, infrastructure and food security of the region.

Answer : The troposphere is one of the lowest layers of the Earth’s atmosphere; it is located right above the planetary boundary layer, and is the layer in which most weather phenomena take place. The troposphere extends upwards from right above the boundary layer, and ranges in height from an average of 9 km (5.6 mi; 30,000 ft) at the poles, to 17 km (11 mi; 56,000 ft) at the Equator. In the absence of inversions and not considering moisture, the temperature lapse rate for this layer is 6.5 °C per kilometer, on average, according to the U.S. Standard Atmosphere. A measurement of both the tropospheric and the stratospheric lapse rates helps identifying the location of the tropopause, since temperature increases with height in the stratosphere, and hence the lapse rate becomes negative. The tropopause location coincides with the lowest point at which the lapse rate falls below a prescribed threshold.

• Since the tropopause responds to the average temperature of the entire layer that lies underneath it, it is at its peak levels over the Equator, and reaches minimum heights over the poles. On account of this, the coolest layer in the atmosphere lies at about 17 km over the equator. Due to the variation in starting height, the tropopause extremes are referred to as the equatorial tropopause and the polar tropopause.
• Given that the lapse rate is not a conservative quantity when the tropopause is considered for stratosphere-troposphere exchanges studies, there exists an alternative definition named dynamic tropopause. It is formed with the aid of potential vorticity, which is defined as the product of the isentropic density, i.e. the density that arises from using potential temperature as the vertical coordinate, and the absolute vorticity, given that this quantity attains quite different values for the troposphere and the stratosphere. Instead of using the vertical temperature gradient as the defining variable, the dynamic tropopause surface is expressed in potential vorticity units (PVU). Given that the absolute vorticity is positive in the Northern Hemisphere and negative in the Southern Hemisphere, the threshold value should be taken as positive north of the Equator and negative south of it. Theoretically, to define a global tropopause in this way, the two surfaces arising from the positive and negative thresholds need to be matched near the equator using another type of surface such as a constant potential temperature surface.

Answer : The ocean is a very complex system and it is never at rest. Ocean currents travel around the planet and go through a lot of ups and a lot of downs along their journey. Because ocean waters are so good at holding heat and because the currents are constantly circulating massive amounts of water, oceans are major players in any discussion on global climate. Ocean currents travel at both the surface of the ocean, as well as deep within the ocean basin. Currents are influenced by factors such as wind, the rotation of the earth, differences in the water’s salt content, temperature and density, and even the shape of the ocean floor. Surface ocean currents are strongly influenced by the wind. Prevailing winds, which are winds that blow predominantly from a particular direction, flow across the ocean surface, pushing the water in large circular ocean currents called ocean gyres.

• Ocean gyres are present in every ocean and move water from the poles to the equator and back again. The water warms at the equator and cools at the poles. Because ocean water temperatures can transfer to the air, the cold and warm waters circulated by the gyres influence the climate of nearby landmasses. Gyres circulation is influenced by the Coriolis Effect, which is the phenomenon created by the rotation of the earth that causes rotation in a clockwise direction in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.

Answer : The central idea of plate tectonics is that the solid, outermost shell of the Earth (the lithosphere) is riding over a weak, partially molten, low velocity zone (the asthenosphere). Continents are looked upon as raft-like inclusions embedded in the lithosphere, while only a thin crust (5 km thick) tops the lithosphere in ocean basins. The thickest continental crust, about 70 km, is reported to lie beneath the Alps. The lithosphere (about 100 km thick) is broken up into about 12, large, rigid plates by rift systems. Each of these plates has been moving as a distinct unit, diverging away or converging towards each other and slipping past one another.

• Along divergent junctions, plates spread apart, being accompanied by intensive volcanicity and earthquake activity. The resulting space between the receding plates is filled by molten, mobile, basaltic material that rises from below the lithosphere. This basaltic magma solidifies in the cracks formed by the rift, producing new sea-floor material that adds to the edges of the separating plates and hence, the name “sea floor spreading” for the whole process which is continuously repeated over and over again.
• Again, when an oceanic plate with a continent at its leading edge collides with another plate carrying a continent, convergence (accompanied by the gradual consumption of the oceanic lithosphere by subduction) gradually closes the oceanic basin in between, producing magmatic belts, folded mountains and mElange deposits on the over-riding continental boundary. This can continue until the two continents collide, when the plate motions are halted, because the continental crust is too light for much of its composition to be carried down to the mantle. Here, the descending oceanic plate may break off, with the complete cessation of subduction at the continent/continental suture, but this can start up again, els1ewhere on the colliding plate. Such continent/continental suture is marked by lofty mountainous chains, made up of highly folded and thrust-faulted rocks, coincident with or adjacent to the magmatic belt. Both giant thrusting and infrastructural nappes lead to considerable crustal shortening and are accompanied by much thickening of the continental crust. An excellent example of continent/continent collision is the Himalayan chain, which began forming some 45 million years ago. This magnificent mountainous chain, with the highest peaks on the surface of the Earth, was created when a lithospheric plate carrying India ran into the Eurasian plate in the Late Eocene time. This can explain how the very thick root underlying the Himalayas was formed.
• The plate tectonic cycle of the closing of an ocean basin by continued subduction of an oceanic plate under a continental one until a continent/continent collision takes place and an intra-continental (collisional) mountain belt is formed, has been called the “Wilson cycle,” after J.T. Wilson, who first suggested the idea that an ancient ocean had closed to form the Appalachian Mountain Belt, and then re-opened to form the present-day Atlantic Ocean.

Answer : Increasing temperature causes seawater to expand in volume and at the same time accelerates the melting rate of glaciers and continental ice caps. Both of these processes contribute to rising sea level. The expansion of polar waters due to reduced salinity further promotes sea level rise. Healthy reefs completely covered with rapidly growing coral colonies, a common sight in tropical waters only a few decades ago, are able to grow upwards faster than the rate of sea level rise. For example, many Jamaican reefs had grown up to 30 meters in thickness since sea level stabilized around 6000 years ago (a rate of about 5 milli meters per year), more than the current rise in sea level of around 2.8 milli meters per year. However the rate of sea level rise rate is accelerating and the degraded reefs that now predominate world wide have too little live coral cover (often only a few percent to a few tens of a percent), and are growing far too slowly for the reef frame work to keep up with sea level rise. These compromised reefs will eventually be drowned, resulting in enhanced rates of coastal erosion.

• Ocean warming and the contributions from fossil fuel use constitute real and pressing priorities requiring prompt attention. The current rise of shallow water, near-shore sea temperatures in virtually all coral reef habitats around the world gives reefs only a few years to a decade or so before they lose their remaining living hard corals, if warming continues at the present rate, less if it accelerates. The fact that all major areas of coastal up welling, responsible for the bulk of the Earth’s pelagic fisheries, are warming faster than the global average indicates that the growing thickness of the warm surface layer is making up welling less effective at bringing cold nutrient-rich water to the surface, causing the collapse of pelagic food chains from the bottom up.

Answer : The types of clouds in the sky, as well as the direction in which they’re moving, can tell a lot about upcoming weather. In general, clouds that are white and high indicate good weather, and clouds that are dark and low mean rain or storms are on the way.

• The presence of cumulonimbus clouds early in the day, with more developing throughout the day can mean there’s a greater chance of severe weather occurring soon.
• Mammatus clouds (formed by sinking air) can form with both severe and non-severe thunderstorms.
• Cirrus clouds, or “mare’s tails,” high in the sky like long streamers, mean bad weather is coming within the next 36 hours.
• Altocumulus clouds, which are like mackerel scales, also point to bad weather coming within the next 36 hours.
• Mackerel skies and mares tails formations sometimes appear in the same sky. When that happens, rain is sure to follow the next day.
• Cumulus towers indicate the possibility of showers later in the day.
• Nimbostratus clouds hang low and heavy in the sky, and mean rain is imminent.
• Cloud cover on a winter night means you can expect warmer weather, because clouds prevent heat radiation that would lower the temperature on a clear night.

Answer : Under the NFSA, PDS ration shops will distribute upto 5kg of foodgrain per person per month to ensure food security for 75% of rural population and 50% and urban population at rice Rs. 3 per kg, wheat Rs. 2 per kg and pulses Rs. 1 per kg. Across the length and breadth of our country, the various states have different production and consumption patterns, at the same time the NFSA centralizes the procurement and allocation process.

• For instance, Tamil Nadu has universalized the food allocation whereas the central arrangement calls for identification and allocation, which is different from the state-approach, which could give rise to a disagreement. There is vast difference in the consumption pattern also. Rice is the staple food of coastal regions whereas northern States as UP, Punjab, Haryana – consumption is more towards wheat.
• Further the NFSA has moved towards the individual from household, this would lead to reduction in allocation to some households. Regional differences in the intake of PDS in household food budget are vast. Whereas in north – central India only about 40% of the people buy grains from ration shops, nearly 85% in the south use food from ration shops.
• However, if the PDS system is reformed according to the different requirements of states being addressed, along with local procurement and distribution, this Act can go a long way in promising food security to the citizens of our nation. As the PDS system matures and proves effective, the states should be brought to have more say in distribution patterns and identification of beneficiaries so as to address their different requirements arising from differing production.

Answer : A new Ministry of Skill Deve-lopment and Entrepreneurship was created recognizing the importance of skill development in India. The immediate mandate of new Ministry is to ensure India meet its target of skilling and upskilling 500 million people in India by 2022. At the same time create an ecosystem that eliminates bottlenecks which makes business easier and encourage entrepreneurship.

Nearly 65 per cent population of the country is below 35 years of age and promotion of skill development will provide ample job opportunities to educated unemployed youth not only in India but abroad as well. It will foster the culture of entrepreneurship in India and will empower new entrepreneurs with the necessary skills and training.

There are poor levels of skills possessed by the vast majority of those joining the workforce each year — a situation that has arisen owing to high rates of school dropouts, inadequate skills training capacity, a negative perception around skilling, and low employability of even those holding professional qualifications, such as degrees in different engineering disciplines.

An additional issue is that these outcomes vary from state to state. Significantly, the bulk of the labour force in India — about 93 per cent — who work in the unorganized sector are largely untouched by any kind of formal training. Net enrolment in vocational courses in India is very low, which is about 5.5 million per year compared to 90 million in China and 11.3 million in the United States (US).

National Skill Development Mission was launched by the Union Government in 2010. The mission consists of three institutions namely National Council on Skill Development, National Skill Development Coordination Board and National Skill Development Corporation (NSDC).

Challenges involved in Skill Development

• Limited capacity: While realizing the transformation of Skill Development, the first major roadblock is the limited capacity vis-a vis the number of aspirants joining the vocational training courses.
• Quality and relevance: Quality and relevance of skill development are key to India’s global competitiveness as well as improving an individual’s access to decent employment. For enterprises to compete in the global economy, the quality of training must reach internationally comparable standards and be relevant to the needs of national and international markets.
• Mismatch: One of the major issues in skill development is mismatch between the demand and supply of skills. Presently the labour market is facing a strange situation, where on the one hand, an employer does not get manpower with requisite skills and on the other hand, millions of job seekers do not get employment. Mismatch between the supply and demand of skills is costly both for the economy and for the individual.
• Low industry participation and Setting up of Sector Skills Council: In order to make the skill development system relevant and driven by labour market signals, it is necessary to increase participation of industries through Sector Skill Councils(SSCs). Functions of SSCs also include identification of skill gaps, preparation of Skill Development plans and establishment of well structured sector specific Labour Market Information System to assist planning and delivery of training.
• Shortage of Trainers: There is a urgent need for improving the quality and size of trainer resource. Skill upgradation of trainers, their quality assurance, and improvement of their status in society are important to improve quality of training.
• Expansion of outreach and equity access: Providing opportunities of Skill Development to all sections of society including women and disadvantaged sections such as SCs, STs, OBCs, minorities and economically challenged and disabled persons of society is necessary to achieve inclusive growth. Also providing skill development opportunities in rural areas, hilly areas, border and difficult areas, naxal affected and remote areas of the country enhancing their access to training; improving employability and increasing employment opportunities for them is essential for development of a just and equitable society.

Answer : On the basis of the location and active geomorphological processes, it can be broadly divided into two: (i) the western coastal plains; (ii) the eastern coastal plains.

• The western coastal plains are an example of submerged coastal plain. Because of this submergence it is a narrow belt and provides natural conditions for the development of ports and harbours. Kandla, Mumbai, JLN port (Navha Sheva), Marmagao, Mangalore, Cochin, etc. are some of the important natural ports located along the west coast. Extending from the Gujarat coast in the north to the Kerala coast in the south, the western coast may be divided into following divisions – the Kachchh and Kathiawar coast in Gujarat, Konkan coast in Maharashtra, Goan coast and Malabar coast in Karnataka and Kerala respectively. The western coastal plains are narrow in the middle and get broader towards north and south. The rivers flowing through this coastal plain do not form any delta. The Malabar coast has got certain distinguishing features in the form of ‘Kayals’ (backwaters), which are used for fishing, inland navigation and also due to its special attraction for tourists.
• As compared to the western coastal plain, the eastern coastal plain is broader and is an example of an emergent coast. There are well developed deltas here, formed by the rivers flowing eastward in to the Bay of Bengal. These include the deltas of the Mahanadi, the Godavari, the Krishna and the Kaveri. Because of its emergent nature, it has less number of ports and harbours. The continental shelf extends up to 500 km into the sea, which makes it difficult for the development of good ports and harbours.

Answer : Soil, by which may be characterised the thin upper part of the Earth's crust where rock (lithosphere), air (atmosphere), water (hydrosphere) and living organisms (biosphere) interpenetrate (pedosphere), is a more complex medium than air and water. Soils are natural entities that exist in a wide range of different types. Soil is composed of both inorganic and organic matter, and with solid, liquid and gaseous components, they contain large numbers of living organisms and are the medium that supports life in its broadest sense. Agriculture has for a long time been based on the notion of the soil as an inexhaustible resource for continually increasing production. On the contrary, because of its very slow formation rate (100-400 years/cm of topsoil), soil must be considered as a non-renewable resource and must be preserved.

Black Soil in India

• Black soils are derivatives of trap lava and are spread mostly across interior Gujarat, Maharashtra, Karnataka, and Madhya Pradesh on the Deccan lava plateau and the Malwa Plateau, where there is both moderate rainfall and underlying basaltic rock. Because of their high clay content, black soils develop wide cracks during the dry season, but their iron-rich granular structure makes them resistant to wind and water erosion. They are poor in humus yet highly moisture-retentive, thus responding well to irrigation. These soils are also found on many peripheral tracts where the underlying basalt has been shifted from its original location by fluvial processes. The sifting has only led to an increased concentration of clastic contents.
• In the upper reaches of the Godavari and the Krishna, and the north western part of the Deccan Plateau, the black soil is very deep. These soils are also known as the ‘Regur Soil’ or the ‘Black Cotton Soil’. The black soils are generally clayey, deep and impermeable. They swell and become sticky when wet and shrink when dried. So, during the dry season, these soils develop wide cracks.
• Thus, there occurs a kind of ‘self ploughing’. Because of this character of slow absorption and loss of moisture, the black soil retains the moisture for a very long time, which helps the crops, especially, the rain fed ones, to sustain even during the dry season. Chemically, the black soils are rich in lime, iron, magnesia and alumina. They also contain potash. But they lack in phosphorous, nitrogen and organic matter. The colour of the soil ranges from deep black to grey.

Answer : "Biological diversity" means the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems.

Human activities affect biodiversity:

• The geometric rise in human population levels leads to habitat destruction (ex. rainforest land is converted to ranches, agricultural land converted into urban areas.)
• Industrial, agricultural and waste-based pollutants have catastrophic effects on many species. (e.g. Water pollution such as acid rain, litter and waste poured into reservoirs, seas or canals can poison the fish and kill other animals that live in the water).
• Thousands of plants and animals are taken from their natural habitats every day to be sold, traded or made into various products, including gifts (ivory from elephant tusks, coral, sea turtle shells and reptile skins are popular souvenirs that threaten species). Other products, like traditional Chinese medicines, can also be made using threatened and endangered animals. For example, tiger bone was often used to help relieve swelling and pain.
• Agriculture has led to conversion of wildlands to croplands, massive diversions of water from lakes, rivers and underground aquifers, and, also has polluted water and land resources with pesticides, fertilizers, and animal wastes. The result has been the destruction, disturbance or disabling of terrestrial ecosystems, and polluted, oxygen-depleted and atrophied water resources.
• The migratory patterns of some birds which live in both tropical and temperate regions during the year seem to be shifting due to global warming.

Role of National Biodiversity authority: The National Biodiversity Authority is mandated to regulate use of India’s biological resources; facilitates/ enable conservation action and provi-des advice to Central and State Governments on issues of conservation, sustainable use and access and benefit sharing.

Answer : Factors responsible for develo-pment of IT industry

• 1960s and 1970s – Indigenization and selfs-ufficiency in computers and electronics largely by national, security related issues – conflict with china and Pakistan. Creation of Electronic commitee.
• Formulation of the national vision for promoting the software industry in India by government in 1980s.
• 1990s liberalisation of economy, development of software techonolgy parks, 2000s formation of ministry of information technology.
• Advantages of cost competitiveness and huge manpower with proficiency in English language.
• Emergence of offshore outsourcing. Exp. USA and Europe.
• Emergence of strong domestic markets- due to high economic growth and development. 4th largset IT market in Asia-Pacific.
• Emergence of large IT companies – Infosys, TCS, Wipro etc.

Answer : The economic impacts of the seaport are classified as:

• Direct impact is the employment and income generated by the direct construction and operation of the port.
• Indirect impact is the employment and income generated by the chain of suppliers of goods and services.
• Induced impact is the employment and income generated by the spending of incomes by employees created by the direct and indirect effects.
• The catalytic impact is the employment and income generated by the role of the port as a driver of productivity growth and then as an attractor of new firms.

Issues related to ports are:

• Inefficient cargo handling and low produ-ctivity
• Equipment utilisation is very poor both because equipment is obsolete and poorly maintained.
• Over staffing at Indian ports remains rampant and productivity indicators in respect of cargo and equipment handling con-tinue to be poor.
• Documentary procedures relating to cargo handling such as customs clearance requirements are unduly complicated and time consuming. Electronic document proce-ssing is still to be introduced in all the ports.
• Port access facilities and arrangements for moving inbound and outbound cargo are inadequate and unsatisfactory.
• Absence of inter-port and intra-port compe-tition which have been conductive to substantial productivity increases in other countries is absent in Indian due to poor inland connectivity and a policy regime that protected domestic ports against competitive pressures.

Answer : An urban heat island (UHI) is a metropolitan area that is significantly warmer than its surrounding rural areas due to human activities. The temperature difference usually is larger at night than during the day, and is most apparent when winds are weak. Seasonally, UHI is seen during both summer and winter.

• The main cause of the urban heat island is modification of the land surface by urban development which uses materials which effectively retain heat. Waste heat generated by energy usage is a secondary contributor. As a population center grows, it tends to expand its area and increase its average temperature. The less-used term heat island refers to any area, populated or not, which is consistently hotter than the surrounding area.

Answer : Impacts of Green Revolution on Environment are:

• The Green Revolution has been widely criticized for causing environmental damage.
• Excessive and inappropriate use of fertilizers and pesticides has polluted waterways, poisoned agricultural workers, and killed beneficial insects and other wildlife.
• Irrigation practices have led to salt build-up and eventual abandonment of some of the best farming lands.
• Groundwater levels are retreating in areas where more water is being pumped for irrigation than can be replenished by the rains.
• Heavy dependence on a few major cereal varieties has led to loss of biodiversity on farms.

Some of these outcomes were inevitable as millions of largely illiterate farmers began to use modern inputs for the first time, but inadequate extension and training, an absence of effective regulation of water quality, and input pricing and subsidy policies that made modern inputs too cheap and encouraged excessive use also created negative environmental impacts.

Answer : COP 11 addressed issues such as capacity building, technology development and transfer, the ad verse effects of climate change on developing and least developed countries, and several financial and budget-related issues, including guidelines to the Global Environment Facility (GEF), which serves as the Convention’s financial mechanism. The achievements are:

• Developed countries agreed to double funding to support efforts in developing states towards meeting
• The internationally-agreed Biodiversity Targets, and the main goals of the Strategic Plan for Biodiversity 2011-2020. The Saragasso Sea, the Tonga archipelago and key corals sites off the coast of Brazil are among a range of marine areas to receive special attention by governments as part of renewed efforts to sustainably manage the world’s oceans agreed in Hyderabad.
• (CBD COP 11) include new measures to factor biodiversity into environmental impact assessments linked to infrastructure and other development projects in marine and coastal areas.
• The COP also set targets to increase the number of countries that have included biodiv-ersity in their national development plans, and prepared national financial plans for biodiversity, by 2015. These targets, and progress towards them, will be reviewed in 2014.
• The 193 Parties to the CBD agreed to classify a diverse list of marine areas, some renowned for containing ‘hidden treasures’ of the plant and animal world, as ecologically or biologically significant.
• At CoP-11, a call was made to Parties and other stakeholders by the Executive Secretary, CBD to pledge urgent action towards achieving Aichi Biodiversity Targets and become one of several Biodiversity Cha-mpions.
• Some other contentious issues which yielded good outcomes during CoP-11 are: geoengi-neering, guidance on safeguards for biodiversity with regard to REDD+, and ma-rine and coastal biodiversity
• The decision to have a third meeting of the Intergovernmental Committee on Nagoya Protocol (ICNP-3), alongwith intersessional work on outstanding issues, as well as supporting initiatives to promote ratification and early entry into force and implem-entation of the Nagoya Protocol is also an important outcome.
• India has also decided to establish a Biodiversity Museum and a Garden in Hyderabad at the site where our Prime Minister unveiled a commemorative Pylon during CoP-11.

Answer : Features of Tropical cyclone

• Tropical Cyclones are climatological pheno-mena that occurs across the globe. They have certain characteristics that distinguish it from other atmospheric disturbances. These are:
• The foremost characteristic is that tropical cyclones are most violent and most disastrous of all the atmospheric disturbances.
• The average speed is 120 kmph, although it may vary from 32 kmph to 200 kmph or more. At times it reaches 400 kmph also.
• They have closed isobars. The pressure gradient is very sharp. More closely spaced isobars represent greater velocity of the storm and viceversa. The pressure at the centre is extremely low. The winds from the surrounding area are drawn towards this low-pressure core called the “eye” of the cyclone.
• Tropical cyclones develop over oceans and seas only. They are most violent and vigorous over water.
• On landfall, their velocity decreases due to friction, and as the source of energy is cut off, they dissipate soon. Thus they affect the coastal areas only.
• The movement of tropical cyclone is affected by the prevailing wind system. Normally they move from east to west under the influence of trade winds.
• They are seasonal in nature and occur during a specific period of the year only.

Answer : El Niño and La Niña are part of the El Niño– Southern Oscillation (ENSO), a natural see-saw in oceanic sea surface temperatures and surface air pressure between the east and west tropical Pacific Ocean. During El Niño events, the trade winds blowing from the east slacken, enabling an eastward migration of warm water. The centre of rain follows, moving east to the middle of the Pacific Ocean near Tahiti. La Niña events behave in the opposite way; the trade winds intensify and stack the warm surface water in the west even more than in normal years—the waters near Australia are often five feet higher than the ocean surface in the east during La Niña episodes. The area of intense rainfall is dragged back toward Australia.

• Sea Surface Temperatures, or SSTs as these are called, play an important role in shaping atmospheric circulations and weather systems across the globe. Indian monsoon too is influenced by SSTs, especially those over the Indian Ocean and Pacific Ocean.
• Known for its disruptive influence on several worldwide weather patterns, El Nino develops when the SST over the central Pacific region becomes warmer than normal.
• Over the south Asian region, of which the Indian subcontinent is a part, El Nino during winter results in development of warm conditions. During summer, it leads to dry conditions over the Indian region and northeast Australia.
• The development of La Nina during winter results in wet conditions over Southeast Asia and northern Australia and wet and cool conditions over Southeast Africa. La Nina during summer causes wet and cool conditions over south Asia, wet conditions over southeast Asia and warm conditions over northeast Australia.
• In the India-specific context, the development of El Nino is known to enhance convection over central Pacific, affect movement of monsoon winds in the Indian Ocean and result in subsidence over many parts. An El Nino phase typically lasts for eight to 10 months and is generally followed by a La Nina episode.
• But El Nino is not the only factor that affects Indian monsoon or causes rain deficit. Scientists, in fact, say that El Nino has no one to- one relationship with monsoon rains. In about 50 per cent of the years with El Nino during summer, India experienced droughts during monsoon.