Reply To: Global warming is well underway

#4303
imported_Martin
Participant

Closely related to the above, a new report from UNEP.

Quote:
The rapid shrinking of Himalayan glaciers, accelerating at alarming rates in past decades as a result of global warming, will have catastrophic consequences for communities living downstream and millions who rely on glacial melt water, a new report says. The report, the first comprehensive study on the impact of warming temperatures on glaciers and glacial lakes in the Himalayan region warns of impending glacial lake outburst floods (GLOFs) – when rising waters from glacial melt breach dams in glacial lakes – and calls for early warning and mitigation measures to avert disaster.

Nearly 15000 glaciers and 9000 glacial lakes are found in the Himalayan mountain chain which stretches 2500 km across five countries – Bhutan, Nepal, Pakistan, India and China. The mountain range feeds nine perennial river systems in the region and constitutes a lifeline for nearly 1.3 billion people downstream.

Himalayan glaciers are shrinking at an average of 10 to 60 m annually, with some retreating by 74 m a year. In China, glaciers have been retreating at a rate of 5.5 per cent in the last three decades. With current climate change projections two-thirds of China’s glaciers are likely to disappear by 2050, and almost all would be gone by 2100.

Significant changes were also seen in the Indian Himalaya, with the highest rate of glacial retreat found in the Bada Shigri Glacier and lowest in the Chhota Shigri Glacier in the Chenab River Basin, where glaciers are retreating by 6.8 to 29.8 m each year.

In Bhutan, the Luggye Glacier retreated by 160 m yearly from 1988 to 1993 resulting in rapid growth of the Luggye Tso Lake. The Raphstreng Glacier retreated 35 m every year on average from 1984 to 1998 but from 1988 to 1993 the retreat rate almost doubled to 60 m per year.

Glacier retreat has been accelerating in Nepal since the 1990s, with dramatic retreats recorded between 1994 and 1998 especially in the Dudh Koshi sub-basin where all of the glaciers studied have retreat by 10 to 59 m yearly. The Dudh Koshi sub-basin is the largest basin and most densely glaciated region in Nepal.

Melting glaciers are also leading to some of the fastest-growing glacial lakes in the region. Some glacial lakes have grown by almost 800 per cent since the 1970s.

Fast Melting Glaciers from Rising Temperatures Expose Millions in Himalaya to Devastating Floods and Water Shortages