Galong Co. Credit: Huang Chen
Revealing “invisible” glacier loss undersea
Current research reveals that the mass loss of lake-terminating glaciers in the Himalayas has actually been severely ignored, due to the restriction of satellites in identifying underwater modifications in glaciers. This has considerable effects for the regions future forecasts of glacier disappearance and water resources
The study was published in the journal Nature Geoscience, and performed by an international cooperation of scientists from the Chinese Academy of Sciences, Graz University of Technology in Austria, the University of St. Andrews in the UK, and Carnegie Mellon University in the United States.
The scientists discovered that a previous evaluation undervalued the overall mass loss of lake-terminating glaciers in the greater Himalayas by 6.5%. The most significant underestimation of 10% took place in the main Himalayas, where glacial lake development was the most fast. An especially intriguing case is Galong Co in this region, with a high underestimation of 65%.
This oversight was mostly due to the restrictions of satellite imaging in spotting underwater changes, which has actually caused a knowledge space in our understanding of the full degree of glacier loss. From 2000 to 2020, proglacial lakes in the area increased by 47% in number, 33% in area, and 42% in volume. This expansion resulted in an estimated glacier mass loss of around 2.7 Gt, equivalent to 570 million elephants, or over 1,000 times the total number of elephants on the planet. This loss was ruled out by previous studies given that the used satellite data can just determine the lake water surface area but not undersea ice that is changed by water.
” These findings have important ramifications for comprehending the impact of regional water resources and glacial lake outburst floods,” said lead author Zhang Guoqing from the Institute of Tibetan Plateau Research, CAS.
Exposing the undetectable glacier loss undersea. Credit: TPE
By accounting for the mass loss from lake-terminating glaciers, the researchers can more accurately assess the annual mass balance of these glaciers compared to land-terminating ones, therefore more highlighting the sped up glacier mass loss throughout the greater Himalayas.
The research study likewise highlights the requirement to comprehend the mechanisms driving glacier mass loss and the underestimated mass loss of lake-terminating glaciers internationally, which is approximated to be around 211.5 Gt, or approximately 12%, in between 2000 and 2020.
” This highlights the significance of integrating subaqueous mass loss from lake-terminating glaciers in future mass-change estimates and glacier advancement models, despite the study region,” said co-corresponding author Tobias Bolch from Graz University of Technology.
David Rounce, a co-author from Carnegie Mellon University, noted that in the long run, the mass loss from lake-terminating glaciers might continue to be a major contributor to total mass loss throughout the 21st century as glaciers with considerable mass loss might disappear more rapidly compared to existing projections.
” By more precisely representing glacier mass loss, scientists can better anticipate future water resource schedule in the sensitive mountain area,” said co-author Yao Tandong, who also co-chairs Third Pole Environment (TPE), an international science program for the interdisciplinary study of the relationships amongst water, ice, environment, and humankind in the area and beyond.
Recommendation: “Underestimated mass loss from lake-terminating glaciers in the higher Himalaya” by Guoqing Zhang, Tobias Bolch, Tandong Yao, David R. Rounce, Wenfeng Chen, Georg Veh, Owen King, Simon K. Allen, Mengmeng Wang and Weicai Wang, 3 April 2023, Nature Geoscience.DOI: 10.1038/ s41561-023-01150-1.
The scientists discovered that a previous evaluation underestimated the total mass loss of lake-terminating glaciers in the higher Himalayas by 6.5%. This oversight was mostly due to the constraints of satellite imaging in discovering undersea modifications, which has actually led to an understanding space in our understanding of the complete degree of glacier loss. This growth resulted in an approximated glacier mass loss of around 2.7 Gt, comparable to 570 million elephants, or over 1,000 times the total number of elephants in the world. This loss was not thought about by previous studies since the used satellite information can only measure the lake water surface area but not undersea ice that is replaced by water.