Kathmandu, June 21
The Hindu Kush Himalayan region has experienced a rapid acceleration of glacier mass loss by to be 65 per cent.
A study carried out by the International Centre for Integrated Mountain Development (ICIMOD) states there has been a significant decrease in the seasonal snow cover during the summer and winter months which has depleted the glacier rapidly. This is largely irreversible, says the report.
The report states snow cover days were declining at an average rate of five snow cover days per decade with most of the changes at lower elevations. Snow cover is likely to experience an accelerated loss in the future thanks to different global warming levels in the Hindu Kush Himalayas.
With rapid glacier melt, most river basins in the region will get ‘peak water’ around mid-century, and overall water availability is expected to decrease by the end of the century, says the report.
The mean temperature is significantly increasing in all the regions of the region with an average observed trend of plus 0.28-degree Celsius per decade (range plus 0.015-degree Celsius per decade to plus 0.34-degree Celsius per decade for individual basins) for the period of 1951-2020.
According to the report entitled ‘Water, Ice, Society, and Ecosystems in the Hindu Kush Himalaya (HI-WISE)’, glacier mass balance has become increasingly negative, with rates surging from minus 0.17 metres of water equivalent per year from 2000-2009 to minus 0.28 metres water equivalent, suggesting an acceleration in mass loss.
For a global warming level between 1.5 to 2 degrees Celsius, the HKH glaciers are expected to lose 30 to 50 per cent of their volume by 2100. The snow cover extent will reduce by between 1 and 26 per cent for an average temperature rise between 1.1 and 4 degrees Celsius.
Change in the active layer thickness ranges from 5-30 cm in 2011-2040 for different warming levels. The active layer thickness is projected to further increase in 2014-2070 and exceed 30 cm in 2071-2099 for warming of 3.1 degrees Celsius or higher above the 1981-2010 baseline.
The report points out recent scientific advances to map the links between the cryosphere, water, biodiversity, and society in the region, shedding light on the impacts of rapid changes in glaciers and snow on people and nature.
The HKH cryosphere is experiencing unprecedented and largely irreversible changes over human timescales particularly guided by climate change.
The impacts according to the report become clear with increased warming at higher elevations, the accelerated melting of glaciers, increasing permafrost thaw, declining snow cover, and more erratic snowfall patterns.