Himalaya Glaciers Shrinking On Global Warming, Some May Disappear

Tan Ee Lyn PlanetArk 2 Aug 11;

Three Himalaya glaciers have been shrinking over the last 40 years due to global warming and two of them, located in humid regions and on lower altitudes in central and east Nepal, may disappear in time to come, researchers in Japan said on Tuesday.

Using global positioning system and simulation models, they found that the shrinkage of two of the glaciers -- Yala in central and AX010 in eastern Nepal -- had accelerated in the past 10 years compared with the 1970s and 1980s.

Yala's mass shrank by 0.8 (2.6 feet) and AX010 by 0.81 meters respectively per year in the 2000s, up from 0.68 and 0.72 meters per year between 1970 and 1990, said Koji Fujita at the Graduate School of Environmental Studies in Nagoya University in Japan.

"For Yala and AX, these regions showed significant warming ... that's why the rate of shrinking was accelerated," Fujita told Reuters by telephone.

"Yala and AX will disappear but we are not sure when. To know when, we have to calculate using another simulation (model) and take into account the glacial flow," Fujita said, but added that his team did not have the data to do so at the moment.

Their findings were published in the journal Proceedings of the National Academy of Sciences on Tuesday.

The Himalayas is an enormous mountain range consisting of about 15,000 glaciers and some of the world's highest peaks, including the 8,848-meter-high Mount Everest and K2.

Apart from climate change and humidity, elevation also appears to play a critical role in the lifespan of glaciers, which are large persistent bodies of ice.

The Rikha Samba glacier in the drier region of west Nepal has also been getting smaller since the 1970s, but its rate of shrinking slowed to 0.48 meters per year in the past 10 years compared to 0.57 meters per year in the 1970s and 1980s.

This was because the 5,700-meter-high glacier was located on a higher altitude, which meant that losses in mass from melting could be compensated at least partly by collection of snowfall, Fujita said.

"In the case of Yala and AX, they are situated on lower elevation (altitudes), therefore shrinkage was accelerated. Glaciers that have no chance to get snow mass will eventually disappear," Fujita said.

Yala glacier is located about 5,400 meters above the sea level, while AX is 5,200 meters high.

(Editing by Yoko Nishikawa)