Researchers have made significant progress toward determining why a few pockets of glaciers in the Karakoram Range are resisting glacial melt caused by global warming, defying the global trend of glaciers losing mass, with the Himalayas being no exception. They attribute the 'Karakoram Anomaly' to the recent revival of western disturbances.
Research Findings:
Himalayan glaciers are critical in the Indian context, particularly for the millions of people who live downstream and rely on these perennial rivers for their daily water needs. They are rapidly receding due to the effects of global warming, and suffocating stress on water resources is unavoidable in the coming decades.
In contrast, the glaciers of central Karakoram have remained stable or slightly increased over the last few decades. This phenomenon has perplexed glaciologists and provided climate deniers with a rare straw to grasp.
Dr. Pankaj Kumar, Associate Professor at the Indian Institute of Science Education and Research (IISER) Bhopal, found this strange because the behaviour appears to be confined to a very small region, with only the Kunlun ranges showing similar trends in the entire Himalaya.
A recent study conducted under his supervision proposed a new theory to explain this defiance of the effects of global warming in certain pockets of the region's glaciers as opposed to other glaciers. His group claimed in a paper published in the Journal of Climate of the American Meteorological Society that the recent revival of western disturbance has been instrumental in triggering and maintaining the Karakoram Anomaly since the turn of the century. The study was funded by the Department of Science and Technology's Climate Change Programme.
For the first time, a study has revealed the significance of increased WD-precipitation input during the accumulation period in modulating regional climatic anomalies.
"Western Disturbances are the primary feeder of snowfall for the region during winters," said Aaquib Javed, a Ph.D. student of Dr. Kumar and lead author of the study. According to research, “they account for roughly 65 percent of total seasonal snowfall volume and 53 percent of total seasonal precipitation, easily making them the most important source of moisture. The precipitation intensity of WDs affecting the Karakoram has increased by around 10% in the last two decades, which only strengthens their role in maintaining the regional anomaly."
The researchers used a tracking algorithm developed at the University of Reading to track and compile a comprehensive catalogue of WDs impacting the Karakoram-Himalayan region over the last four decades. The analysis of the tracks passing through the Karakoram reveals the importance of snowfall in mass balance estimations.
While previous studies have focused on the role of temperature in establishing and maintaining the anomaly over time, this is the first time the role of precipitation in feeding the anomaly has been highlighted. The researchers also calculated the role of precipitation in feeding the anomaly.
According to the scientists' calculations, the contribution of WDs in terms of snowfall volume over the core glacier regions of the Karakoram has increased by about 27 percent in recent decades, while precipitation from non-WD sources has decreased by about 17 percent, supporting their claims.
"The anomaly offers a very bleak but still hopeful ray of hope for delaying the inevitable." "Now that we've recognized the importance of WDs in controlling the anomaly, their future behaviour may very well decide the fate of Himalayan glaciers," Dr. Kumar said.
