Himalayan Glaciers resisting Global Warming

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Recently, researchers have taken a significant leap toward solving the mystery of why few pockets of glaciers in the Karakoram Range are resisting glacial melt due to global warming

• The study was supported by the Climate Change Programme of the Department of Science and Technology.

Key Findings

• Glaciers are fast receding under the impacts of global warming, and stifling stress on the water resources is inevitable in the coming decades. 
• Defying normalcy: This trend is defying the trend of glaciers losing mass across the globe, with the Himalayas being no exception. Researchers have attributed this phenomenon called ‘Karakoram Anomaly’ to the recent revival of western disturbances (WDs). 
• The glaciers of central Karakoram have surprisingly remained unchanged or slightly increased in the last few decades. This phenomenon has been puzzling glaciologists and providing climate deniers with a very rare straw to clutch at.
• The behaviour seems to be confined to a very small region, with only Kunlun ranges being another example of showing similar trends in the whole of Himalaya.
• Western Disturbances are the primary feeder of snowfall for the region during winters. 
  • The study suggests they constitute about around 65% of the total seasonal snowfall volume and about 53% of the total seasonal precipitation, easily making them the most important source of moisture. 
  • The precipitation intensity of WDs impacting Karakoram has increased by around 10% in the last two decades, which only enhances their role in sustaining the regional anomaly.
• The analysis for the tracks passing through the Karakoram reveals the role of snowfall as a crucial factor in mass balance estimations.
• The researchers have also quantified the impact of precipitation in feeding the anomaly.
  • Calculations by the scientists reveal that contribution of WDs in terms of snowfall volume over the core glacier regions of Karakoram have increased by about 27% in recent decades, while precipitation received from non-WD sources have significantly decreased by around 17%, further strengthening their claims.

Image Courtesy: Research Gate 

Glacier

• It is a big body of ice that is created from falling and accumulated snow over a period of time.
• They get created in areas where the temperatures are exceedingly low, including areas that are at sea level and mostly in high altitude areas like the mountain tops.

Significance of Glaciers

• Fulfils Water needs: Himalayan glaciers are of paramount importance in the Indian context, especially for the millions of dwellers living downstream who rely on these perennial rivers for their day-to-day water needs.
• Ocean Currents: The melting fresh water from glaciers alters the ocean, not only by directly contributing to the global sea level rise, but also because it pushes down the heavier salt water, thereby changing what scientists call the THC, or Thermo (heat) Haline (salt) Circulation, meaning currents in the ocean.
• Indicators of climate change: Glaciers are sentinels of climate change. They are the most visible evidence of global warming today.
• Irrigation: Artificial glaciers can provide more water for crops and drinking during seasonal dry periods.
• Hydroelectric power: The electricity can be generated using glacial resources by damming glacial meltwater.

Reason of Melting Glaciers

• Climate change, which is altering the patterns of temperature and precipitation and larger anthropogenic modifications of the atmosphere.
• Deposits of anthropogenic Black Carbon (BC), which increase the glaciers’ absorption of solar radiation and raise air temperatures.
• There is scientific consensus that ice loss from glaciers and polar ice sheets results from rising global temperatures caused by greenhouse-gas emissions from the burning of fossil fuels.
  • Many peer-reviewed scientific studies have identified human activity as a cause of rising global temperatures.
  • A United Nations Intergovernmental Panel on Climate Change  report issued in August 2021 also highlighted that human influence is very likely the main driver of the global retreat of glaciers since the 1990s.
• The regional climate factors, such as shifts in the South Asian monsoon, may play a role.

Impacts 

• The Himalayan mountains are also referred to as the third pole because they hold the world’s third-largest amount of glacier ice, following Antarctica and the Arctic. 
• The ice melt threatens agriculture and water supply for millions of people in South Asia and will contribute to rising sea levels that threaten coastal communities across the world.
• It also adds to the threat of inundation and related problems faced by coastal communities around the world.

• Rising sea levels can cause soil erosion and jeopardise the structural integrity of roads and bridges as well as power plants and other critically important industrial facilities located in coastal areas. 
• As the glaciers continue to shrink, the availability of water for irrigation and drinking water could drop steeply.

Conclusion

• The Karakoram anomaly provides a very bleak but nonetheless a ray of hope towards delaying the inevitable. 
• After recognising the importance of WDs in controlling the anomaly, their future behaviour might very well decide the fate of Himalayan glaciers as well.

Source: PIB