Thajwas 95% gone

Srinagar, May 18: The Thajwas Glacier near the tourist resort of Sonamarg has lost nearly 95 percent of its ice spread since the last Ice Age and is now “a relict of a glacier,” according to a study by researchers from the University of Kashmir (KU) and the Inter-University Accelerator Centre (IUAC), New Delhi.

The study ‘Paleo-glacial re-construction of the Thajiwas glacier in the Kashmir Himalaya,’ found that the glacier, which covered nearly 54 sq km during the global Last Glacial Maximum (gLGM) around 20,770 years ago, has now shrunk to about 2.76 sq km.

“Thajwas is now a relict of a glacier,” said Prof Ghulam Jeelani, Head of the Department of Earth Sciences, KU. “What we are seeing today are merely remnants of a much larger glacier system that once occupied the entire valley.”

The findings were published in Geoscience Frontiers by Omar Jaan Paul, research scholar, Department of Earth Sciences, KU; Prof Shakil Ahmad Romshoo, Vice Chancellor, Islamic University of Science and Technology (IUST), Awantipora, and former head of the Department of Earth Sciences, KU; Reyaz Ahmad Dar, Assistant Professor, Department of Earth Sciences, KU; Soumya Prakash Dhal, researcher, Department of Geo-Informatics, KU; and Pankaj Kumar and Sundeep Chopra, scientists at the IUAC, New Delhi.

Using cosmogenic radionuclide-Beryllium-10 exposure dating and geomorphological mapping, the researchers reconstructed the glacier’s evolution over the last 20,000 years and identified four major glacial stages associated with the Last Glacial Maximum, the Younger Dryas cold phase, the Early Holocene and the Neoglaciation period.

According to the study, the glacier’s ice volume declined from about 2.73 cubic km during the Ice Age to only 0.09 cubic km at present. Researchers said the glacier lost nearly 64 percent of its area and 73 percent of its volume between the Last Glacial Maximum and the Neoglaciation phase around 4200 years ago.  The retreat accelerated sharply afterward.

“From the Neoglaciation period to the present day, the glacier lost around 85.74 percent of its area and 87.67 percent of its volume,” the study said.

The researchers also found that the glacier’s equilibrium line altitude – the elevation where annual snowfall equals melting-shifted upward by around 873 meters, moving from 3365 meters above sea level during the Ice Age to 4238 meters today. “This upward shift reflects sustained warming in the Himalayan region,” the study said. “The temperature rise has significantly altered glacier mass balance.”

The study estimated that temperatures in the Thajwas valley during the Last Glacial Maximum were about 5.7 degrees Celsius lower than present-day conditions, enabling the glacier to extend nearly 10 km farther down the valley than its current position.

Researchers said changing climatic conditions reduced ice accumulation while accelerating melting, leading to the glacier’s drastic retreat over time.

The findings provide one of the first absolute glacial chronologies from the Kashmir Himalaya and could help scientists better understand long-term climate variability and future glacier response in the region, the researchers said. “The reconstruction of paleo-glacial history is important for understanding how Himalayan glaciers respond to climatic shifts,” the researchers said. “It also helps in assessing future risks linked to glacier retreat and water security.”