Advances in satellite technology have revealed that the world’s glaciers contain significantly less ice than previously thought, according to a study https://doi.org/10.1038/s41561-021-00885-z published in Nature Geoscience on Monday.
The revised estimate decreases global sea level by 3 inches if all the glaciers melt. However, it raises concerns for some communities that depend on seasonal melt from the glaciers to irrigate crops and feed rivers. Water will run out faster than expected if glaciers have less ice. Some ice melts naturally throughout the year. However, rising temperatures caused by climate change are accelerating glacier retreat. Between 2000 and 2019, these rivers of ice lost https://www.reuters.com/business/environment/climate-changes-study-finds-worlds-glaciers-melting-faster-2021-04-28 roughly 5.4 trillion tonnes.
Countries are already struggling https://www.reuters.com/article/us-bolivia-environment-glacier-idUSKBN29929U with disappearing glaciers. Peru is investing in desalination https://www.reuters.com/article/environment-peru-water-dc-idUKN1161583720080311 to make up for declining freshwater. And Chile hopes to create artificial glaciers https://www.reuters.com/world/americas/conservationists-chile-aim-freeze-water-man-made-glaciers-2021-10-28 in its mountains. Romain Millan (Universit Grenoble Alpes glaciologist) said that there is not enough information to determine how much ice is actually in glaciers. Past analyses, such as those that double-counted glaciers on the edges of the Greenland or Antarctic ice sheets, have overestimated ice volume.
The Nature Geoscience study evaluated the speed with which glaciers were moving across the landscape. These measurements allow scientists to measure volume more accurately, as the flow of glaciers can indicate where ice thickness or thickness. Technology has made it difficult to collect this information. Millan stated that high-resolution satellites, which were launched in recent years, allowed for the first analysis on how 98% world’s glaciers are moving. “From small glaciers within the Andes to massive glaciers Svalbard, and Patagonia,” Millan said.
The study examined more than 800,000 pairs photographs of glaciers taken between 2017-2018 and found that many were significantly shallower than previously believed. Scientists now believe there is 20% less glacial ice, which could melt into the ocean and raise sea level. Glaciers are currently responsible for a mm of annual sea-level rise, or 30% of the annual increase. “This is one the first really impressive results coming from satellite advances,” said Daniel Farinotti (ETH Zurich glaciologist), who was not involved in the research.
Millan and his associates also discovered that Asia’s Himalayas have 37% more ice than previously thought, while South America’s Andean glaciers have approximately 27% less. Already, Peru’s glaciers lost 40% of their surface area in the 1970s. He said, “This will place more pressure on freshwater supplies in the Andes.” “On the contrary, water in the Himalayas will be more safe.”
(This story is not edited by Devdiscourse staff.