Q) Discuss the endogenous elements that contribute to the creation of volcanoes with the aid of suitable examples.

Students are expected to provide a thorough overview of the endogenous elements that contribute to the creation of volcanoes along with pertinent examples.

Introduction:

Endogenic forces are those movements that are caused by forces that originate from the earth’s core. The contraction and expansion of rocks as a result of changes in thermal conditions and temperature within the earth is what gives rise to endogenic force. Many landforms were created as a result of these processes, including volcanoes.

Body:

Volcano formation-related endogenic factors:

Earth’s interior heat is the primary energy source for the forces that propel endogenic processes.

Diastrophic motions and abrupt movements are two categories of endogenic movements.

According to plate tectonics, most volcanoes form when two lithospheric plates collide and one of them slides over the other, pushing the other plate deep into the mantle where it will be reabsorbed.

Ocean floor spreading: Along the axis of the oceanic ridge system, where the plates move apart on both sides of the ridge and magma wells up from the mantle, is a significant site of active volcanism.

Weak Earth Surface: Because of high pressure in the earth’s interior, the magma and gases escape with great velocity as the pressure is released through eruptions where opportunity is provided by weak zones along the earth’s surface.

Faults: Whenever extreme pressure builds in the mantle, along fault lines an eruption is likely to happen next. The earthquakes, for instance, may expose fault zones through which magma may escape and volcanoes can be formed.

Magma crystallization: Decreasing temperatures can cause old magma to crystallize and sink to the bottom of the chamber and this movement can force fresh liquid magma up and out – similar to dropping a brick in a bucket of water.

Plate movement: Volcanism may occur because of plate movement over a “hot spot” from which magmas can penetrate to the surface. e.g. Islands of Hawaii

Conclusion:

It is due to these endogenic elements that volcanoes arise. Volcanoes are further categorised as Active, Dormant, and Extinct depending on their level of activity. Volcanoes not only serve a significant role by cooling the majority of the planet, but they also provide ash and lava, which breaks down to create soil and minerals.

Q) How are different regions of the world affected by changes in the Asian Monsoon’s patterns? Provide an explanation using current examples.

Candidates are expected to explain in detail how changes in the Asian monsoon pattern have affected different regions of the world using relevant, current instances.

Introduction:

One of the strongest meteorological occurrences on Earth and one of the most significant for society is the Asian monsoon. Important seasonal rainstorms that water crops and forests as well as destructive typhoons and floods are all caused by the monsoon.

Body:

80%–85% of the annual rainfall in the afflicted areas, which frequently amounts to 1.5–2.5 metres, occurs during the summer monsoon season.

On longer timescales, scientists have frequently pointed to the millions of years of evolution of this seasonal wind flow as a major factor in past changes to the environments, biosphere, and oceanography of this region, which includes the Indian subcontinent, Southeast Asia, China, Korea, and Japan. The Asian Monsoon pattern has changed in the ways listed below:

Since 1976, when there has been a regime change in climate around the world – from a weak to a strong El Nio phase, the monsoon has been delayed practically every year.

The length of the rainy season has decreased as a result of the monsoons ending about a week earlier than they used to – at the end of September.

There are frequently sporadic “break times” throughout the monsoon season when little rain falls. Systems departing the equatorial region and heading north are responsible for these times. The length of the “active periods” when it does rain is getting shorter as a result of global warming, while the break periods are getting longer, according to all available data and models-blended-with-data (known as reanalysis).

Impact of altered Asian monsoon patterns on different regions of the world:

The Indian monsoon is regarded as a well-defined “textbook phenomena” that hasn’t changed much over the past century.

Unfortunately, this process has encountered an inconsistent front, with floods in the northwest and northeast and a lack of rainfall in the country’s south.

Over the past few years, rainfall extremes have grown tenfold and now cover the entirety of central India, from Gujarat to Odisha.

Since 2002, the monsoon has started later each year and lasts for a shorter amount of time, compressing the Indian monsoon.

As a result of more frequent pauses in the monsoon, the monsoon itself has longer, drier periods.

In the last 10 or two years, there has been a dramatic change in rainfall intensity, duration, frequency, and spatial distribution.

In many areas of India, cycles of drought and flooding have increased in frequency, and their severity has shifted over time. Consider Cyclone Amphan.

Moreover, cyclones are also beginning to hit the countries’ western coasts. Consider Cyclone Vayu.

Areas that have traditionally received plenty of rainfall are often remaining dry, while places that are not expected to get a lot of monsoon rain have sometimes been getting flooded.

The intensity and amount of rainfall over the region has increased drastically. For instance, Typhoon Kammuri in Phillipines and Flooding in parts of China.

The agricultural cycle of sowing to harvesting is facing tremendous challenge as unprecedented breaks and excess rainfall in short period of time making difficulty to set sowing pattern.

Many of the metro cities are receiving excessive rainfall as compared to their average normal. e.g. Recent flooding in Mumbai.

Also some experts opined that Australian bushfires partly due to late monsoon ending in India.

The lack of water in other areas has hit water table levels. By 2030, India is expected to require almost 1.5 trillion m3 of ground water, where the current supply is only 740 billion m3, putting a huge pressure on the river basins, which are facing challenges of their own due to fast-disappearing glaciers and reduced rainfall.

In recent times it is proved that monsoons are (nearly) unpredictable natural disasters. Hence, following steps are needed to tackle this crisis:

Need to change crop cycles, credit cycles, create storage infrastructure to deal with flooding.

We need to invest in developing the state of the art technology to predict the accurate data regarding the monsoon cycle.

Also, we need modification in the approach of handling of disasters by NDRF and SDRF as the intensity of the rainfall is extreme in some cases.

 Change in the type and variety of crops and change in the kind of inputs used by farmers to deal with the altered reality is needed of the hour.

Conclusion:

The impact of the monsoon cycle changing on various regions of the world is significant. But, using cutting-edge technology and spending more on study to understand how the Asian monsoon is changing would undoubtedly assist to properly address this situation and prevent any losses in the future.

Q)How do wetlands develop? How are they distributed globally? Why do they matter so much to the ecosystem? Explain.

Candidates need to write about wetlands first. Then, simply as requested, describe how it is generated and how it is distributed worldwide. Before the conclusion, emphasise how important it is to the ecosystem.

Introduction

Wetlands are regions where water plays a major role in regulating the environment and the plant and animal life that goes along with it. They manifest themselves where the land is submerged in water or where the water table is at or close to the surface of the ground.

Body

The development of wetlands

Broad coastal marshes that are shielded from wave action by barrier islands or reefs have been produced as a result of flooding of coastal lowlands caused by rising sea levels.

River floodplains are created by erosion processes and the depositing of sediment during floods on nearby regions.

9,000–12,000 years ago, glaciers contributed to the development of wetlands in the northern states. Glaciers dammed rivers, carved out valleys, and altered floodplains, resulting in the formation of huge wetlands.

Wetlands can also grow in “sink holes” and other places where bedrock has been broken down by percolating water. By obstructing rivers or forcing terrain to sink down close to the water table or seashore, earthquakes can generate wetlands.

Wetlands are made by people. Some “incidental” wetlands are created as a result of irrigation work, building highways and dams, and other human endeavours that change drainage patterns or impound water.

River floodplains are created by erosion processes and the depositing of sediment during floods on nearby regions.

9,000–12,000 years ago, glaciers contributed to the development of wetlands in the northern states. Glaciers dammed rivers, carved out valleys, and altered floodplains, resulting in the formation of huge wetlands.

Wetlands can also grow in “sink holes” and other places where bedrock has been broken down by percolating water. By obstructing rivers or forcing terrain to sink down close to the water table or seashore, earthquakes can generate wetlands.

Wetlands are made by people. Some “incidental” wetlands are created as a result of irrigation work, building highways and dams, and other human endeavours that change drainage patterns or impound water.

worldwide distribution

Mangroves like the Sundarbans in India and Bangladesh’s Ganges delta, the Niger Delta region in Nigeria and Cameroon, and the Orinoco and Gulf of Paria deltas in Venezuela’s east coast.

When the rate of evapotranspiration increases, salt marshes and inland wetland systems, such as Scarborough Marsh, Morecambe Bay, and Portsmouth in Britain, and the Bay of Fundy in North America, experience saline conditions.

Tidal freshwater marshes include those along the Rhine and Thames in Europe, the Yellow River (Huang He) in Asia, and the St. Lawrence River between the United States and Canada.

Peatlands Tropical peatlands are found in the lowlands of East Asia and Southeast Asia, the Caribbean, Central and South America, and Africa.

Freshwater forested swamps are dominated by trees or other woody vegetation found for example from Delaware to Texas and along the Mississippi River.

Riparian wetlands occur along rivers and streams that periodically overflow their channel confines, causing flooding to which the wetland vegetation is adapted. Occur in the Amazon Basin of South America, in Bangladesh, and in the floodplains of large rivers such as the Mississippi in the United States.

Importance:

About two thirds of the world’s fish are caught in wetlands, which are very productive environments.

Microbes, plants, and wildlife found in wetlands are involved in the world cycles of water, nitrogen, and sulphur. Instead of releasing carbon dioxide into the sky as carbon monoxide, wetlands store carbon within their plant communities and soil.

Wetlands serve as natural barriers that hold back and gradually release floodwaters, rainwater, snowmelt, and surface water.

Wetland vegetation also lessens soil erosion and slows the speed of flood flows, lowering flood heights.

Several of them maintain a broad variety of life, supporting plants and animals that are unique to that area, and they serve as habitat for both animals and plants.

Conclusion

Effective collaborations among stake holders along with proper implementation of schemes are required for overall management of wetlands.