Faster snowmelt in Himachal despite increased cover – The New Indian Express

Express press service

CHANDIGARH: Greater snow cover in Himachal Pradesh has melted at a faster rate this year due to a sudden increase in temperatures in March-April this year.

This is the conclusion of a study conducted by the State Center on Climate Change under the aegis of the Himachal Pradesh Council for Science Technology and Environment (HIMCOSTE) in collaboration with the Space Applications Center (ISRO) in Ahmedabad.

At the beginning of this year, Himachal experienced a rich snowfall which was 19.47% more in the area under the snowfall in the winters of last year. The happy news lasted just a month, however, as a sudden rise in temperatures caused the snowpack to melt at a faster rate, reducing it by 19-25% from 4-10% last year. .

The study predicts reduced snow cover in the coming months in various river basins across the state, affecting hydroelectric generation in downstream areas and water scarcity.

The study indicates that about a third of the total geographic area of ​​the hills state remains under heavy snow cover during the winter season.

Most major rivers such as the Chenab, Beas, Parvati, Baspa, Spiti, Ravi, Satluj and its perennial tributaries originating from the Himalayas depend on seasonal snow cover, in addition to the contribution of glaciers for their reliability of debit.

In addition, snow cover also helps control the accumulation and ablation patterns of the state’s glacial regions. Speaking to this newspaper, HIMCOSTE Senior Scientific Director SS Randhawa said that due to early winters last year and snowfall in October, more areas had fallen under snow. The maximum change was noticed in the Ravi catchment, where snow cover increased from 127 km (2020-21) to 2,167 km (2021-22) – an increase of around 1,594%.

But due to early summers this year, the snow cover melted quickly as the temperature in April rose nearly eight degrees above normal this year.

“April analysis, which is considered the start of the ablation period, shows a downward trend in snow cover in all four basins. In other words, we can say that the snow cover has been released due to an April melt of between 19 and 27 percent compared to 2020-21,” Randhawa said.

Compared to the corresponding months in 2021, the maximum temperature increased by 3.00C in May this year in the Chenab basin, while in the Ravi basin the temperature increase was 2.30C in March, 6 .10C in April and 3.50C in May. In Chamba and Dalhousie, the rise was 2.10C, 7.60C and 5.00C in March, April and May, respectively. Similarly, the temperature increase in the Satluj Basin was 2.80C in March, 8.20C in April and 2.90C in May.

“Due to this abrupt increase in temperature in all basins, the rate of melting was accelerated in all basins, resulting in a reduction in snow cover in each basin,” the study said.

According to Randhawa, if the trend also continues in the coming winter season, this depletion will have a serious impact on the state’s hydropower sector, leading to water shortages in downstream areas.

Lalit Jain, HIMCOSTE Member Secretary, said snowmelt and snowfall patterns have become quite unpredictable due to climate change.

CHANDIGARH: Greater snow cover in Himachal Pradesh has melted at a faster rate this year due to a sudden increase in temperatures in March-April this year. This is the conclusion of a study conducted by the State Center on Climate Change under the aegis of the Himachal Pradesh Council for Science Technology and Environment (HIMCOSTE) in collaboration with the Space Applications Center (ISRO) in Ahmedabad. At the beginning of this year, Himachal experienced a rich snowfall which was 19.47% more in the area under the snowfall in the winters of last year. The happy news lasted just a month, however, as a sudden rise in temperatures caused the snowpack to melt at a faster rate, reducing it by 19-25% from 4-10% last year. . The study predicts reduced snow cover in the coming months in various river basins across the state, affecting hydroelectric generation in downstream areas and water scarcity. The study indicates that about a third of the total geographic area of ​​the hills state remains under heavy snow cover during the winter season. Most major rivers such as the Chenab, Beas, Parvati, Baspa, Spiti, Ravi, Satluj and its perennial tributaries originating from the Himalayas depend on seasonal snow cover, in addition to the contribution of glaciers for their reliability of debit. In addition, snow cover also helps control the accumulation and ablation patterns of the state’s glacial regions. Speaking to this newspaper, HIMCOSTE Senior Scientific Director SS Randhawa said that due to early winters last year and snowfall in October, more areas had fallen under snow. The maximum change was noticed in the Ravi catchment, where snow cover increased from 127 km (2020-21) to 2,167 km (2021-22) – an increase of around 1,594%. But due to early summers this year, the snow cover melted quickly as the temperature in April rose nearly eight degrees above normal this year. “April analysis, which is considered the start of the ablation period, shows a downward trend in snow cover in all four basins. In other words, we can say that the snow cover has been released due to an April melt of between 19 and 27 percent compared to 2020-21,” Randhawa said. Compared to the corresponding months in 2021, the maximum temperature increased by 3.00C in May this year in the Chenab basin, while in the Ravi basin the temperature increase was 2.30C in March, 6 .10C in April and 3.50C in May. In Chamba and Dalhousie, the rise was 2.10C, 7.60C and 5.00C in March, April and May, respectively. Similarly, the temperature increase in the Satluj Basin was 2.80C in March, 8.20C in April and 2.90C in May. “Due to this abrupt increase in temperature in all basins, the rate of melting was accelerated in all basins, resulting in a reduction in snow cover in each basin,” the study said. According to Randhawa, if the trend also continues in the coming winter season, this depletion will have a serious impact on the state’s hydropower sector, leading to water shortages in downstream areas. Lalit Jain, HIMCOSTE Member Secretary, said snowmelt and snowfall patterns have become quite unpredictable due to climate change.

Teresa H. Sadler