Thinning glaciers in the Himalayas bad news for climate change: Studies

Two recent studies have thrown more light on the condition of the glaciers across Himalayas and also those from the TransHimalayan region of Ladakh Although the thinning melting and receding of glaciers have been known for quite some time now every new study comes as an alarm for humanityIn their latest published study a bunch of researchers have studied the Pangong Tso region of Ladakh and ascertained the area changes and frontal retreat of 87 glaciers between 1990 and 2019 using satellite data Besides the glacier outlines were delineated manually and compared with existing regional and global glacier inventories that are available over the regionThis analysis indicated deglaciation of 67 per cent from 1990 to 2019 over the Pangong Region with cleanice glaciers showing a higher retreat of 84 per cent compared to the debriscovered glaciers 57 per cent However the overall recession is lower compared to other parts of northwestern Himalayas the study published in the study titled Spatiotemporal dynamics and geodetic of glaciers with varying debris cover in the Pangong region of TransHimalayan Ladakh India between 1990 and 2019 published in Frontiers in Earth Science journal in December 2021 saidFrom 2000 to 2012 the glaciers lost an ice mass amounting to 033 to 005 metre water equivalent m we per year The only thing is that the mean glacier elevation did not indicate any influence on glacier recessionUnlike this another study published last week found out that glaciers on Mount Everest such as South Col Glacier which is located at the highest point in the world have been thinning at an alarming rate with estimated thinning rates of nearly two metre per yearThe study published in the Nature Portfolio journal Climate and Atmospheric Research as reported by IANS addresses a key question from the 2019 National Geographic and Rolex Perpetual Planet Everest Expedition on whether glaciers at the highest point on earth are experiencing the impacts of climate change And the Mount Everest region has indeed been losing ice significantly since the late 1990s it was revealedSo do we know everything about Himalayan glaciersIt has been known for quite some time that the Himalayan glaciers are showing recession due to multiple reasons including climate change Even the government is aware of and maintains data regarding melting of Himalayan glaciersIt is also known that the glaciers in eastern central and western parts of the Himalayas are reacting differently to different causes such as climatic conditions topography and geological influences The Western part also includes the Karakoram ranges and the TransHimalayan Ladakh region which is supposed to be relatively stable compared to the rapidly changing eastern or central partsThe Himalayas are called the third pole as it is the repository of the highest volume of ice outside the two poles As many as 10 major rivers of the Indian subcontinent originate from the Himalayas and Indias 45 per cent population is directly or indirectly dependent on HimalayasMelting glaciers have significant impact on water resources of Himalayan rivers due to change in glacier basin hydrology downstream water budget impact on hydropower plants due to variation in discharge flash flood and sedimentation They also increase in risk related to glacier hazards due to enhanced number and volume of glacier lakes accelerated flash flood and Glacial Lake Outburst Floods GLOFs impact on agro practices in high Himalayan region etcMultiple government agencies have been studying the glaciers albeit the effort is far too less given the vast number of glaciers 1015000 known large glaciers and numerous smaller ones spread across the Himalayas with most of them difficult to reachIn the just concluded Budget Session of the Parliament Lok Sabha member Dushyant Singh had asked if the government is aware of the study conducted by the University of Leeds regarding the rapid melting of Himalayan glaciers published in journal Nature Scientific Reports in 2021The government agreed that it was aware of it and pointed out the difference between the findings of the multiple studies The University of Leeds the Minister for Earth Sciences Dr Jitendra Singh answered had reconstructed the size and ice surfaces of 14798 Himalayan glaciers during the Little Ice Age which was 400700 years agoThe study concludes that the Himalayan glaciers have lost ice 10 times more quickly over the last few decades than on average since the last major glacier expansion In the last 400 to 700 years the glaciers have lost around 40 per cent area shrinking from 28000 sq kms to around 19600 sq kmThe Minister also listed the various Indian institutesuniversitiesorganisations such as Geological Survey of India the Wadia Institute of Himalayan Geology the National Centre for Polar and Ocean Research the National Institute of Hydrology the Space Application Centre the Indian Institute of Science IISc etc that monitor Himalayan glaciers for various scientific studies including glacier meltingThe NCPOR has utilised Rs 1188 crore during the last five years for Himalayan Glacier research Rs 1544 crore has been utilised by DST and Rs 11 crore by GSI during the last five years he saidThese studies have reported accelerated heterogeneous mass loss in Himalayan glaciers The mean retreat rate of Himalayan glaciers is in the range of 149 to 151 metreannum ma which varies from 127 to 132 ma in Indus 155 to 144 ma in Ganga and 202 to 197 ma in Brahmaputra river basins However glaciers in the Karakoram region have shown comparatively minor length change from minus 137 to 228 ma indicating the stable conditionThe Ministry of Earth Sciences through its autonomous institute NCPOR is monitoring six glaciers in the Chandra basin 2437 sq km area in western Himalaya since 2013 The rate of annual mass balance melting ranging from minus 03 to 006 metre water equivalent per year m wey1 to minus 113 to 022 m wey1 during 20132020 Similarly a mean thinning of approx 50 metres with a mean annual mass loss of minus 109 to 032 m we y1 was observed for the Baspa basin during 20002011The GSI has taken up a project on melting of glaciers in Beas Basin South Chenab basin and Chandra Basin in Himachal Pradesh Shyok and Nubra basin in Ladakh during Field Season 202122The Department of Science and Technology DST has supported various RampD projects for studying Himalayan Glaciers under the National Mission for Sustaining Himalayan Ecosystem and National Mission on Strategic Knowledge for Climate ChangeThe mass balance studies conducted for some Himalayan glaciers by University of Kashmir the Sikkim University the IISc and the WIHG revealed that the majority of Himalayan glaciers are melting or retreating at varying ratesWIHG is monitoring a few glaciers in Uttarakhand which reveal that the Dokriani Glacier in the Bhagirathi basin is retreating at 1520 ma since 1995 whereas Chorabari Glacier in the Mandakini basin is retreating at 911 ma during 20032017 WIHG is also monitoring DurungDrung and Pensilungpa glaciers in Suru basin Ladakh which are retreating at 12 ma and approximately 56 ma respectivelyThe NIH has been conducting several studies for the assessment of runoff from melting of glaciers at catchment and basin scales across Himalayas The recent publication suggests that at regional scale mass loss rate varies between minus 041 to 011 mwey1 in the eastern minus 058 to 001 mwey1 in the central minus 055 to 037 mwey1 in the western Himalaya and minus 010 to 007 mwey1 in Karakoram region in the last decade the Lok Sabha was toldThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoever