An international team of researchers has concluded that climate change has greatly affected the previously stable region of the Tibetan Plateau, causing the devastating avalanche of 2016.
Published in an issue of the Journal of Glaciology, the study was done by researchers from the Chinese Academy of Sciences joined by two glaciologists from The Ohio State University: Lonnie Thompson, Distinguished University Professor in the School of Earth Sciences and research scientist at the Byrd Polar and Climate Research Center, and Ellen Mosley-Thompson, Distinguished University Professor in Geography and director of the Byrd Polar and Climate Research Center.
Tibet has avoided climate change for decades despite glaciers in southern and eastern Tibet melting at an increasing rate. Extra snowfall had most likely created additional meltwater according to Lide Tian, a glaciologist at the Institute of Tibetan Plateau Research of the Chinese Academy of Sciences and lead author of the paper.
More than 70 million tons of ice broke off from the Aru glacier in western Tibet, falling onto nomadic yak herders in the valley below. "Given the rate at which the event occurred and the area covered, I think it could only happen in the presence of meltwater," Thompson said. Other nearby glaciers may be headed the same way, he added, "but unfortunately as of today, we have no ability to predict such disasters."
According to Thompson, the most vital fact about the avalanche was that it only lasted four or five minutes but still buried 3.7 square miles of the valley floor in that time. Thompson believes that the meltwater at the base of the glacier could have sped the avalanche's descent down the mountain.
Another glacier in the same mountain range gave way a couple of months later, this time without fatalities. Researchers were able to get precise measurements of how much ice fell in the first avalanche by utilizing satellite data and GPS. By working with computer modelers who were able to replicate the avalanche virtually, the researchers were able to conclude by the simulations that the cause of the avalanche was the presence of meltwater.
"We still don't know exactly where the meltwater came from, but given that the average temperature at the nearest weather station has risen by about 1.5 degrees Celsius (2.7 degrees Fahrenheit) over the last 50 years, it makes sense that snow and ice are melting and the resulting water is seeping down beneath the glacier," Thompson explained.