Researchers at Nagaland University, Lumami and Cotton University, Guwahati, have documented significant glacier retreat in Arunachal Pradesh over the past three decades posing a threat of flooding in the region.

The Himalayas are home to the largest concentration of glaciers outside the polar regions. These glaciers serve as a freshwater source for over 1.3 billion people living downstream. Rapid glacial retreat in recent decades has raised concerns about long-term water availability and ecological balance.

The Research was led by Dr Latonglila Jamir of Nagaland University and Dr Nabajit Hazarika, of Cotton University, Guwahati, with research scholars Vimha Ritse and Amenuo Susan Kulnu of Nagaland University.

Dr. Latonglila Jamir, Associate Professor, Department of Environmental Science (Lumami Campus), Nagaland University, said, “The study used Remote Sensing (RS) and Geographic Information Systems (GIS) to analyze glacier changes in Arunachal Pradesh from 1988 to 2020. Most glaciers in the region are situated between 4,500 and 4,800 meters above sea level. The consequences of glacier retreat extend beyond the immediate region. Communities that depend on glacial meltwater for agriculture and drinking water may face water shortages in the future. Initially, melting glaciers may lead to flooding and unstable river flows, but over time, reduced glacial mass will result in lower water availability. The formation and expansion of glacial lakes also pose risks, as sudden floods caused by glacial lake outbursts (GLOFs) can be destructive.

The results show a marked reduction in glacier coverage. In 1988, there were 756 glaciers covering around 585.23 square kilometers. By 2020, the number had dropped to 646, with the total area shrinking to 275.38 square kilometers. The researchers estimated an average glacier loss of 16.94 square kilometers per year. Smaller glaciers (less than 5 square kilometers) were found to be retreating faster.

The researchers said that the need for continued monitoring and better climate adaptation strategies to manage water resources in the region. As climate change continues to reshape the Himalayas, studies like this one provide data that can help inform decisions on water management and disaster preparedness.