Glacial Lake Outburst Floods

Why in news?

Recently Birendra glacial lake in Nepal collapsed due to avalanche.

What is the glacial lake outburst flood?

• Glacial lakes- They are large bodies of water that sit in front of, on top of, or beneath a melting glacier.
• Glacial Lake Outburst Floods (GLOFs)- They are sudden and often catastrophic events that occur when water contained within or underneath a glacier or a moraine-dammed glacial lake is released rapidly.
• Causes- These floods typically result from the failure of natural dams made of ice, moraine (a mixture of rock, soil, and other debris), or both.

• Ice and debris avalanches- Avalanches of ice, rock and debris can impact glacial lakes, causing the release of large volume of water, avalanches occur due to various factors such as seismic activity, steep slopes or destabilization of ice and rock masses.
• Ice dammed lakes- Some glacial lakes are dammed by ice instead of moraine, when the ice dam melts or collapse, it can release large volumes of water downstream triggering GLOF.
• Earthquake- Seismic activity, including earthquakes can destabilize glacial lakes and their surrounding terrain, leading to failure of natural dams and release of water.
• Volcanic eruption- It can trigger GLOFs by melting ice, causing landslides or generating lahars (volcanic mudflows) that can impact glacial lakes.
• Anthropogenic activities- Activities such as mining, construction, and deforestation can destabilize the landscape, increase erosion, and contribute to the risk of GLOFs.
• Vulnerable- GLOFs pose a significant risks to communities living downstream of glacial lakes, especially in mountainous regions like Himalayas, Andes and Alps, where such lakes are common.

Why Himalayas are more prone to Glacial Lake Outburst Floods?

• High glacial activity- The Himalayas are called as Third Pole it harbours world’s largest glaciers after Arctic and Antarctic ice sheets.
• Glacial melting- As temperatures rise due to climate change, these glaciers are melting at an accelerated rate, leading to the formation of numerous glacial lakes which increases the risk of GLOFs.

ISRO said that 130 of the 676 lakes are situated in India, in the Indus (65), Ganga (7), and Brahmaputra (58) river basins have expanded as glaciers are retreating at an ever faster rate due to global warming.

• Glacial lake formation- Glacial lakes in the Himalayas are often dammed by unstable moraines, ice, or bedrock, these natural dams are susceptible to erosion, melting, and other forms of degradation, increasing the likelihood of failure and the release of floodwaters downstream.
• Steep terrain- The Himalayan region is characterized by rugged, steep terrain, which can contribute to the destabilization of glacial lakes and their surrounding moraines.
• Unstable movements-Avalanches, landslides, and rockfalls are common in this environment, posing risks to the stability of natural dams and increasing the likelihood of GLOFs.
• Seismic activity- The Himalayas are seismically active, with frequent earthquakes and tectonic activity, they can trigger landslides, avalanches, and the destabilization of glacial lakes, leading to GLOFs.
• Monsoon climate- The Himalayan region experiences heavy monsoon rains during the summer months, which can increase the volume of water in glacial lakes and contribute to the weakening of natural dams.
• Population density- The Himalayan region is densely populated, with communities living in valleys downstream of glacial lakes. This increases the potential impact of GLOFs on human lives, infrastructure, and livelihoods.

What can be done to mitigate GLOFs?

• Artificial drainage- Lowering the water level of glacial lakes can significantly reduce the risk of outburst floods.
• Study of Ghepan Gath lake, Himachal Pradesh- It showed that lowering lake levels by 10 to 30 meters had a significant impact reduction on Sissu town, the risks were not completely eliminated but still can minimize potential consequences of GLOF.
• High Density Polyethylene (HDPE) pipes- In 2016, Sikkim used HDPE pipes to reduce water levels in South Lhonak Lake.
• Risk assessment- Researchers need to continuously monitor the lakes for signs of instability and potential outburst events, this includes using satellite imagery and developing models to predict GLOF risk.

Satellite remote sensing technology by ISRO proves to be an excellent tool for monitoring due its wide coverage and revisit capability

• Early warning systems- Establishing effective early warning systems is critical for minimizing damage and casualties, these systems should utilize real-time monitoring data to provide timely alerts to downstream communities in the event of a GLOF threat.
• International cooperation- The GLOFs in the Himalayas can affect multiple countries, international cooperation is essential which can foster collaborative efforts such as sharing data, resources and expertise to better understand and mitigate the risks posed by glacial lakes.
• Research- Continued research into glacial dynamics, climate change impacts, and GLOF mitigation strategies is necessary to develop innovative approaches that reduce GLOF risk.

Quick facts

References

1. The Print- Avalanche sets off glacial lake outburst in Nepal
2. Indian Express- Anlysis of glacial lake by ISRO

Conserve Soil for Food Security

Why in news?

India did not sign the agriculture agreement in COP 28 as it would involve significant changes in agricultural policies and farming practice.

What are the challenges of food security?

• Population growth- Homo sapiens took over 200,000 years to reach a population of 1  billion in 1804, however the next billion was added in just 123 years by 1927.
• Climate change- It leads to extreme weather events such as droughts, floods, and heatwaves, which can devastate crops and livestock.
• Limited natural resource- Land degradation, water scarcity, and depletion of natural resources pose significant challenges to food production. Soil erosion, pollution, and overexploitation of water resources diminish agricultural productivity and threaten long-term food security.
• Poverty- It limits people’s access to food by constraining their purchasing power and reducing their ability to produce or purchase food.
• Income inequality - It heightens disparities in access to food, with marginalized communities often facing the greatest barriers to food security.
• Conflict- It disrupts food production, distribution, and access, leading to food shortages, displacement, and humanitarian crises.
  • Example- Gaza and Haiti on the brink of famine due to ongoing war and crisis by criminal gangs respectively
• Trade barriers-Practices such as tariffs, and subsidies distort global food markets and can hinder access to affordable and nutritious food.
• Environmental degradation- Deforestation, biodiversity loss, and pollution degrade ecosystems and reduce their capacity to support agriculture.
• Food waste- Significant amounts of food are wasted or lost throughout the supply chain, from production and processing to distribution and consumption.

What are the impact of food security policy on environment?

• Soil degradation- Heavy subsidies on chemical fertilizers, particularly urea, have led to imbalanced use of nitrogen (N), phosphate (P), and potash (K). which made soil deficient in organic carbon.
• Poor Soil Organic Carbon (SOC)- The optimal SOC level should be between 1.5% and 2%, but 60% of Indian soils have SOC levels below 0.5% due to excessive use of chemical pesticides.
• Loss of biodiversity- The use of HYV seeds displaced indigenous species and agricultural system that has led to loss of biodiversity and agricultural genetic resources aggravating the genetic vulnerability of many valuable gene pools.
• Groundwater depletion- Groundwater levels are falling in many Indian states, with critical conditions in Punjab, Haryana, and Rajasthan. This is attributed to free electricity for irrigation, minimum support prices, and unrestricted procurement of paddy, leading to excessive groundwater use.
• Ecological impact- The overuse of groundwater has resulted in an ecological crisis, with the water table dropping annually and paddy fields emitting about 5 tons of carbon per hectare.
• Loss of crop diversity-  Policies have caused a shift in crop patterns, particularly in Punjab where rice cultivation increased from 4.8% in 1960 to over 40% today, replacing other crops like maize, millets, pulses, and oilseeds.
• India’s status- India, with only 2.4% of the world’s geographical area, 4% of global freshwater resources, and 18%  of the world’s population, is under huge stress, be it its soils, water, air (GHG emissions) or biodiversity.

What lies ahead?

• The need of the hour is to implement policies that are beneficial to both peasant and the planet to save future generation.
• A holistic approach must be implemented to handle the climate change and extreme weather events are likely to increase causing massive damage to lives and livelihoods.
• Immediate action must be taken to create climate-resilient food systems, restore soil health, halt groundwater depletion, significantly reduce greenhouse gas emissions, and incentivize biodiversity conservation through green credits.

References

1. Indian Express- To ensure a hunger free nation protect soil
2. IGNOU- Green Revolution

Prelim Bits 30-04-2024 | UPSC Daily Current Affairs

Declaration of the poll at a polling station to be void

The Election Commission of India (ECI) declared void the poll in certain polling stations of Manipur, and Arunachal Pradesh and conducted the repolls.

• Reasons for declaring the poll void - India’s election laws provide a framework for handling situations where the normal polling process is disrupted for any reason, including
  • Damage to EVMs,
  • Booth-capturing,
  • Natural disasters,
  • A candidate’s death.

Reference

The Indian Express | What EC can do if normal polling process is disrupted

Hangor Class Submarines

China has launched the 1^st of the eight Hangor-class submarines for its all-weather ally Pakistan to provide it with state-of-the-art warships.

• Origin of the agreement - The contract for building the submarines between Pakistan government and China Shipbuilding & Offshore International Company Ltd. was signed in 2015.
• Built by - 4 of the 8 submarines will be built by Wuchang Shipbuilding Industry Group’s (WSIG) while others are being built at KS&EW (Karachi Shipyard & Engineering Works) under Transfer of Technology agreement.
• Hangor-class Submarine – It is an export variant of the Chinese Type 039A Yuan class and is named after PNS Hangor, which famously sank Indian frigate INS Khukri during the 1971 war.
• Features - The submarines come with diesel engines and an air independent propulsion (AIP) system thus its durabulity underwater.
• It can launch anti-ship missiles and Babur-3 subsonic cruise missile which has a 450 km range thus giving Pakistan the deep strike capabilities.
• Pakistan’s Hangor class is the direct counterpart of India’s Kalavari class of submarines, based on the French Scorpene-class.

Quick facts

References

The Indian Express | Pakistan’s new Hangor class submarines,

FirstPost | China launches first Hangor-class submarine for Pakistan

Supreme Court stand on Streedhan Property

The Supreme Courtreiterated that stridhan is an “absolute property” of a woman, and while the husband has no control over the same.

• Streedhan properties - Properties gifted to a woman before marriage, at the time of marriage or at the time of bidding farewell or thereafter are her streedhan properties.
• It is her absolute property with all rights to dispose at her own pleasure.

• Supreme Court verdict – Streedhan property does not become a joint property of the wife and the husband, and the husband has no title or independent dominion over the property as its owner.
• The husband may use it during the time of his distress but nonetheless he has a moral obligation to restore the same or its value to his wife.

Reference

Economic Times | Husband’s control over wife's stridhan

Salmonella infection (Salmonellosis)

In the last six months, a third of MDH Pvt Ltd’s shipments of spice products were rejected by the US because of salmonella contamination.

• Cause - Also known as salmonellosis, it is a common bacterial disease that affects the intestinal tract.
• Salmonella bacteria typically live in animal and human intestines and are shed through stool (feces).
• Transmission - The infection is highly contagious and can be transmitted person-to-food-to-person, animal-to-person directly, animal-food-person, and even person-to-person.
• Humans may contract salmonella infections, usually by eating food with live bacteria on it (undercooked or contaminated food or drinking contaminated water).
• Symptoms - Diarrhoea, abdominal cramps, a fever, nausea, and vomiting in some cases.
• Treatment - It is a self-limited illness that will go away in a few days, but in some cases it requires medical intervention.
• Cooking foods to a safe internal temperature, usually 165 degrees, and proper food safety are important for prevention of salmonellosis.

India is the world’s largest producer, consumer and exporter of spices.

Related links – Ethylene dioxide

Reference

Firstpost | US rejects MDH over salmonella contamination

Kalesar Wildlife Sanctuary

The Supreme Court has stayed the construction of 4 dams in the Kalesar Wildlife Sanctuary following the Wildlife Institute of India’ report.

• Location – Haryana
• Notified in - 1996
• Kalesar National Park (KNP) and Kalesar Wildlife Sanctuary (KWLS) is the westernmost tip of the Terai Arc Landscape with the Shivalik mountain range.

Kalesar National Park is named after the Kaleshwar (shiva) temple located in protected area. The Yamuna River flows on the one side of the park.

• Coverage - An area of 11,000 acres
• The sanctuary derives its name from the Kalesar forest, which is a part of the reserve.
• Important flora – Red junglefowl, grey partridge, Indian peafowl, and white-throated kingfisher.
• The Kalesar forest boasts a dense cover of Khair and Sal trees.
• Important fauna - Leopards, sambar deer, barking deer, hyenas, jackals, Indian porcupines, Indian pangolins, and langurs.
• Key features - The topography varies from plains to hills up to an elevation of 700 m, interspersed with narrow valleys locally called ‘khols’ between the hills.
• These valleys house seasonal rivulets locally called ‘soats’ which remain dry for most of the year.
• This site qualifies as a key biodiversity area of international significance (including Important Bird and Biodiversity Areas, Alliance for Zero Extinction sites, and Key Biodiversity Areas).
• Dams within Kalesar Wildlife Sanctuary - Chikan, Kansli, Khillanwala and Ambawali.

References

1. Tribune India | SC stays 4 dams inside  Kalesar Wildlife Sanctuary
2. WWI | Kalesar Wildlife Sanctuary