New Delhi: The Himalayas, the world’s highest mountains, are getting warmer, according to a study published in science journal Current Science.
“Total precipitation (rainfall + snowfall) was found to increase whereas snowfall was found to decrease with concurrent significant increase in rainfall at all zones of NWH," the study said.
It warned that rising trends in liquid precipitation have a negative influence on Himalayan glaciers and “frequency of hazards such as avalanches and landslides is expected to increase during late winter".
The study analysed wintertime variability in climatic parameters like temperature (maximum, minimum and mean) and precipitation over Northwestern Himalaya (NWH) along with its constituents — Lower Himalaya (LH), Greater Himalaya (GH) and Karakoram Himalaya (KH) — during three time scales 1991–2015 (25 years), 1991–2000 (10 years) and 2001–2015 (15 years).
It was done by H.S. Negi, Neha Kanda, M.S. Shekhar and A.Ganju of the central government’s Snow and Avalanche Study Establishment, Chandigarh.
It said the “impact of global warming is evident over NWH in form of rising maximum and mean temperature at all zones and NWH".
“An overall warming signature was observed over NWH since maximum, minimum and mean temperatures followed rising trends with a total increase of 0.9 degrees Celsius, 0.19 degrees Celsius and 0.65 degrees Celsius respectively, in 25 years, the increase being statistically significant for maximum and mean temperatures. However, warming was not consistent over all zones of NWH," said the study published this week.
“Interestingly, snowfall amount is found to have decreased whereas rainfall amount have increased in 25 years. Furthermore, precipitation at all zones except LH follows decreasing trends in last 15 years (2001–2015) which signals significant climatic change especially after year 2000," it added.
This is significant as changes in snow and ice cover affect air temperature, sea level and storm patterns.
“The increase in liquid precipitation during winter months over seasonal snow has induced enhanced melting and flood situation in Kashmir recently (5–7 April 2017). Such rising trends in liquid precipitation over snowfall, have a negative influence on the Himalayan glaciers. In addition, the frequency of hazards like avalanches and landslides is expected to increase during late winter," it warned.
The study, however, cautioned that, “such observations must be validated with other sources of information depicting climate change like extent of glaciated areas and vegetation cover over different regions of NWH".
The study is significant as mountains in the Himalayan region are active in the regulation and redistribution of water resources as they contain headwater of many major rivers like the Ganges, Brahmaputra and Indus.
The study stressed that it is believed that high elevation environments comprising glaciers and permafrost are among the most sensitive indicators of climate change.
“Detailed study of climate change impacts on water resources of Asia is crucial since glacial melt runoff in the continent is expected to increase in near future, thereby prompting water scarcity in the longer run due to global warming," it added.