Himalayas: Up there it’s getting warmer, faster

The Himalayas are warming more rapidly than the rest of the planet.

Researchers have found that the average annual mean temperature during the 25-year period from 1982 to 2006 increased by 1.5°C, with an average increase of 0.06°C per year — three times more than the global average of temperature rise in the same period. This has had an effect on rainfall too.

The findings, which were published on Tuesday, are from a study conducted by researchers associated with the University of Massachusetts, Boston and the Bangalore’s Ashoka Trust for Research in Ecology and the Environment.

Principal author Uttam Babu Shrestha of the University of Massachusetts, said, “Our study confirmed that the Himalayas region is experiencing rapid climate and associated changes in various ecoregions.”

It shows changes in temperature and precipitation in the Himalayas — greater than the upper bounds predicted by the Intergovernmental Panel on Climate Change and recent assessments.

The Brahmaputra Valley semi-evergreen forest ecoregion has experienced the greatest rate of warming, 2.0°C (0.08°C per year), and the Northern Triangle temperate forest ecoregion the least, 0.25°C (0.01°C per year).

More alarming are changes in rainfall pattern and phenology. The study has found a consistent trend of increasing average precipitation in the Himalayas as a whole. Also, the average start of growing season (termed, SOS) has advanced in some regions, and delayed in others.

The study argues that the relationship between temperature and SOS might be location-dependent.