UPSC CSE Mains Syllabus: GS-3- Conservation, environmental pollution and degradation, environmental impact assessment
Changing Glaciers – Climate Change
The changes in glaciers in the Nanda Devi region of Central Himalayas in Uttarakhand in the last three decades have majorly affected the lifestyle, culture and agricultural practices of people living in nearby villages, says a study carried out by experts from major institutes including IIT Kanpur, Wadia Institute of Himalayan Geology (WIHG), Uttarakhand Space Application Centre (USAC) and HNB Garhwal Central University in Uttarakhand.
What does the research say:
- The research conducted on the ‘changes in glaciers and associated drivers for the last three decades, Nanda Devi region, Central Himalayas’ was done by studying the state of glaciers from 1980 till 2017 through extensive ground surveys and satellite imagery.
- During the study, which started in 2002 and was completed in 2018, it was found that about 26 sq km of the glaciated area of the Nanda Devi region was lost in 37 years which affected the people living in nearby areas.
- The changes in the glaciated areas had a major effect on various aspects of the life of people living in about 47 villages in the buffer zone of the Nanda Devi Biosphere Reserve hosting the Nanda Devi glaciers.
- It was found that the people in those villages who used to wear heavy winter clothing due to low temperatures, had stopped wearing them due to climatic changes in the last few decades which have caused the receding of glaciers there.
Agricultural practices and housing changed
- The locals in the region were now growing a wide variety of vegetation which points to a change in the agricultural practices as well.
- Their agricultural practices have also changed.
- Earlier they used to grow only buckwheat, potato and kidney beans.
- But now they have started growing green vegetables also due to the change in temperature and climate over the last three decades.
- During the ground surveys for the study it was found that food habits and housing designs have also changed.
- They used to build houses with logs and grass on the roofs to bear the snowfall.
- Due to the climatic changes, the snowfall has stopped but rains have started due to which they are now using tiles on the roofs which used to be unthinkable a few decades ago.
Major effect on the cultivation of apples:
- One of the major effects has been on the cultivation of apples in the area and livelihood of the people in the villages.
- Earlier the chilled variety of apples like Golden delicious was cultivated in those areas but it has now stopped because of rise in temperatures due to which those apples could not grow.
- Similarly, the locals in those villages used to collect medicinal herbs from the jungles and sell for their livelihood.
- That has been also affected as those herbs are now growing less due to climatic changes.
- The areas vacated by the glaciers are now occupied by vegetation which used to grow in lower regions.
- During the study, the team of researchers examined eight glaciers in the Upper Rishi Ganga catchment in Nanda Devi region.
- In 1980, the Upper Rishi Ganga catchment which covers an area of 690 sq km had a glaciated area of about 243 sq km, about 35% of the total area. In 2017, it reduced to 217 sq km, a loss of 26 sq km.
- Now the total glaciated area is only 26% of the total area.
- The study also suggested that the glaciers in the region have responded to deprived precipitation conditions since 1980, overlapping our understanding of glacier retreat due to temperature increase in the context of global warming scenario.
- He informed that it was found that the largest glacier of the region, UND glacier covered an area of 71.42 sq km in 1980 which was reduced to 63.72 sq km in 2017.
- Similarly, the smallest one, Changbang which occupied 7.85 sq km in 1989, had shrunk to 5.95 sq km in 2017.
- It was also found that the north-facing glaciers such as Trishul, DRB and Raunthi lost the minimum percentage area compared to south-facing ones like Changbang and Ramni.
- This shows that the slope and aspect play a very important role in glacier change variability.
Non-climatic factors – role in variable loss of glaciers:
- The dynamic response of glaciers to climate is strongly dependent on glacier size and geometry.
- It can be suggested that besides global warming, the local climatic and non-climatic factors like aspect and slope, play an important role in variable loss and dynamics of glacier snouts even in the same valley.
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