Recent Trends in Melting Glaciers, Tropospheric Temperatures over the Himalayas and Summer Monsoon Rainfall over India

This report by the Division of Early Warning and Assessment (DEWA), United Nations Environment Programme (UNEP), looks at claims about climate change impacts on the Himalayas, sometimes referred to as the ‘Third Pole’ Three Indian organisations collaborated with the UNEP on this report – the Institute of Green Economy (Gurugram), The Energy Resources Institute (TERI) University (New Delhi), and Sharda University (Greater Noida).The report summarises discussions that took place at a two-day international workshop in Delhi (December 28-29, 2009) titled ‘Emerging Issues in Climate Change – State of Tropospheric Temperature, Pollution, Melting Glaciers and their Potential Impact on Monsoon and High Altitude Vegetation in the Himalayas-Tibetan Plateau’. The workshop was attended by representatives of government, international organisations, experts, scientists, and academics. The report has two chapters: the first looks at literature on glacial melting, while the second assesses how the Himalayas affect summer monsoon rainfall in India.Chapter 1 says that the retreat of Himalayan glaciers has mostly been attributed to global warming. However, there is some disagreement about this, both in scientific interpretations and statistics. The chapter also has a long and detailed list of studies that provide evidence for the retreat and advance of several Himalayan glaciers. Chapter 2 says that an increase in the concentration of aerosols over the Indian Ocean has caused a weakening of the monsoon rainfall and leads to frequent droughts in the country. However, there are other factors, such as dust mixed with soot aerosols that have advanced the monsoon rainfall to early summer. In conclusion, the report recommends inter-country efforts to pool data in order to arrive at more reliable conclusions.