SHIKHAR Mains 2023 Day 34, 20 July Model Answer English

Q1. भारत के तट के साथ पाए जाने वाले महासागरीय संसाधनों की सूची बनाइए। इन संसाधनों के कुशल उपयोग में आने वाली चुनौतियों की भी चर्चा कीजिए। (12 अंक)

Enlist the ocean resources found along the coast of India. Also discuss the challenges in efficient utilisation of these resources. (12 Marks)

Approach: 

• The introduction highlights the importance of the Indian ocean.

• Enlist the resources found along the coast of India.

• Discuss the challenges in efficient utilization of these resources.

• Conclude with a way forward.

Answer:

The Indian Ocean is a major conduit for international trade, especially energy. Its littoral is vast, densely populated, and comprises some of the world’s fastest growing regions. The ocean is also a valuable source of fishing and mineral resources. 

Resources in coastal regions of India:

Mineral resources: 

• Nodules containing nickel, cobalt, and iron, and massive sulphide deposits of manganese, copper, iron, zinc, silver, and gold present in sizable quantities on the sea bed.

• Indian Ocean coastal sediments are important sources of titanium, zirconium, tin, zinc, and copper. Rare earth elements are present, even if their extraction is not always commercially feasible.

Energy resources: 

• The main energy resources present in the Indian Ocean are petroleum and gas hydrates. Petroleum products mainly include the oil produced from offshore regions. Gas hydrates are unusually compact chemical structures made of water and natural gas.

• Tidal Energy: Like conventional hydroelectric dams, power plants are built on river estuaries and hold back huge amounts of tidal water twice a day which generates electricity when released. India is expected to have 9,000 MW of tidal energy potential. Total identified potential of Tidal Energy is about 12455 MW, with potential locations identified at Khambhat & Kutch regions, and large backwaters, where barrage technology could be used.

• Offshore wind energy: Offshore wind in India has a potential of approximately 70 GW mainly of Tamil Nadu and Gujarat coasts. Eight zones each of the coasts of Gujarat and Tamil Nadu have been identified as potential shore zones. 

• Wave Energy: This is generated by the movement of a device either floating on the surface of the ocean or moored to the ocean floor.

Fishery Resource : 

• India has about 8118 Km. of coastal line and nearly 2 million Sq Km of Exclusive Economic Zone (EEZ) and half a million Sq Km. of Continental Shelf. From these marine resources, India has an estimated fisheries potential of 4.41 million tonnes.

Challenges:

• Uncertainty of the marine environment and commercial scale risks like- corrosion of materials due to the salinity of seawater, offshore maintenance difficulties, the environmental impact on landscapes and the marine ecosystem and competition from other marine activities such as fishing.

• The Indian coastal regions are faced with the common pressing challenges of increasing urbanisation, industrialization and migration, resulting in over-exploitation of natural marine resources.

• It has been about 40 years since India started efforts to assess and harness tidal power but it is yet to achieve any solid breakthrough in its development even as the country made rapid strides in boosting other sources of renewable power. “There is potential for tidal energy in India, but India is yet to develop a technology or major project for tidal energy,

• One of the reasons, according to the ministry, for not pursuing tidal power is “exorbitant cost”. India had started two tidal power projects of 3.75 megawatts and 50 megawatts installed capacity in 2007 and 2011 in West Bengal and Gujarat respectively. But both these projects were dropped because of exorbitant costs. 

• Multi-dimensional challenges from climate change impacts such as sea-level rise, ocean acidification, and extreme weather events. Climate change impacts like erosion and inundation could cause loss of coastal habitats such as mangroves, thereby affecting the reproduction of species.

• The densely populated littoral is also vulnerable to natural or environmental disasters. For ex., the 2004 tsunami that killed 228,000 people. Managing humanitarian assistance and disaster relief (HADR) operations is a challenge.

India needs to transform from the conventional economy to the Blue economy for efficient, environmentally sensitive and effective utilisation of marine resources. The concept of blue economy  based on the idea of a healthy ocean supporting productive and sustainable ecosystems, is bringing about an integration of ocean activities with the principles of social inclusion, environmental sustainability, and innovative, dynamic business models.

Q2: समुद्री धाराएँ क्या होती हैं? ये तटीय क्षेत्रों की जलवायु को कैसे प्रभावित करती हैं? व्याख्या कीजिए।

What are ocean currents? How do they affect the climate of coasts? Illustrate.

Approach:

• First of all, bring out factors which are responsible for the origin and modification of the ocean

• currents and elaborate them briefly.

• Then, with examples, elaborate how ocean currents determine the climate of surrounding regions.

Answer:

OCEAN CURRENTS- Ocean currents are like river flow in oceans. They represent a regular volume of water in a definite path and direction.

The factors responsible for the origin and modifications of ocean currents can be enumerated as:

• Origin – It is attributed to density differences in different layers of ocean waters. Heavier water sinks and causes the overlying surface water to move in its space. This gives rise to global oceanic circulation.

• Other factors – Accumulation of water on east coasts leads to gravity induced movements down the slope.

• Expansion due to heat – Even though water is considered practically incompressible, minor expansion due to excess solar heat in equatorial regions causes a slight gradient and water tends to flow down the slope.

• Modification – Wind, Coast line and inundation, large river discharge, presence of partially enclosed seas.

• Periodic reversals due to heating and accumulation can also cause modification such as in case of ElNino current caused by a stronger counter equatorial current.

• Coriolis force - This force intervenes and causes the water to move to the right in Northern Hemisphere and to the left in the Southern Hemisphere. These produce large circular currents in all the Ocean basins. One such circular current is in the Sargasso Sea.

Ocean currents have direct and indirect effects on the climate of the regions. These can be enumerated as:

• West coasts of the continents in Tropical and subtropical are bordered by cold currents. Their average temperatures are relatively low with narrow diurnal and annual ranges. There is fog, but generally areas are arid due to the desiccating effect leading to formation of deserts in the area. Example. Cold Peruvian current- Atacama Desert.

• East coasts of the continents in the middle and higher latitudes are bordered by warm currents which cause a distinct marine climate. They are characterized by cool summer and relatively mild winters. E.g. China type of climate.

• Warm currents flow parallel to east coasts of the continents in tropical and subtropical latitudes. This result in warm and rainy climates. E.g. Florida.

• Foggy weather and drizzle in the mixing zones of warm and cold current.