Ground Report | New Delhi: What is happening to the Himalayan glaciers; The ice loss in Himalayan glaciers has accelerated since 2000, with nearly half a meter of ice melting every year due to rising temperatures, with some areas increasing by up to 1ºC. The consequences are many, such as floods or water shortages, according to a study published in 2019.
What is happening to the Himalayan glaciers
The research, embodied in the study, has analyzed the changes that have occurred during the last four decades in the Himalayan regions. This has happened from the images obtained by the American spy satellite KH-9 Hexagon, known as “Big Bird” and used during the years of the so-called “Cold War” and which, in 2011, were declassified. These images have been joined by others obtained by NASA in India, China, Nepal, and Bhutan.
Some images whose relevance is that they are the clearest to reflect “how fast the Himalayan glaciers are melting during this period of time, and what are the reasons”. This was explained at the time by Joshua Maurer, lead author of the work, belonging to the Lamont-Doherty Observatory of Columbia University.
To carry out the research, 650 Himalayan glaciers were analyzed. 55% of all the ice in the region, and occupying an area, from west to east, of 2,000 kilometers. The observed progression was that, for example, in 1975, the Himalayan area had an ice mass of 87%, which was maintained in 2000 and dropped to 72% in 2016. In other words, in a matter of four decades, a quarter of its mass has been lost.
It is a loss of 25 centimeters of ice per year due to the increase in temperature produced by climate change between 1975 and 2000, with an evident acceleration throughout the 1990s and, in the following, with In the new millennium, it increased in such a way that a loss is estimated, since then, of 50 centimeters a year.
A thaw with serious consequences
Furthermore, it has been observed that the thaw in the Himalayas has mainly affected the lower altitudes. Up to five meters per year of ice loss per year. This represents about eight million tons of water lost. The consequences are really serious because it could affect about 800 million people. This lack of water implies problems for irrigation, hydroelectric power and access to drinking water, and healthy sanitation. Although the thaw has produced water that circulates freely on the ground, the so-called runoff, in the medium and long term it will cause water shortages.
As for the causes, two seem to be the main factors. On the one hand, the increase in temperature, which has produced changes in rainfall in the area, decreasing in some areas and increasing others. On the other, the massive burning in Asian regions of fossil fuels and biomass, whose ash ends up on snowy surfaces, absorbing solar energy and promoting and accelerating the thaw.
Climate change also causes floods
Unfortunately, the melting of glaciers in the Himalayas is not the only way that climate change is hitting this region. Simulations designed and conducted by researchers at the University of Potsdam suggest that thousands of lakes are at risk of dangerous flooding. This would happen as rising global temperatures continue to melt snow and ice.
This thaw causes the moraines – barriers formed of sediments and rocks joined by ice – to give way. This generates what the researchers call ‘Glacial Lake Burst Floods’. Through millions of computer simulations using topographic map data and satellite studies, the researchers found around 5,000 lakes that had unstable moraines and that can cause these floods.
Most glacial lakes are in sparsely populated areas. However, communities living downstream could be affected by these floods, which also affect agricultural lands and can damage infrastructure.