Scrutinise the variations of glaciers and their climatic attributions in the Sanjiangyuan National Park during 1969–2018

Abstract

Since 2020, the first national park of China, the Sanjiangyuan National Park (Park) has been put into operation in China. This Park is one of the most vulnerable regions to the rapid climate change in the Tibetan Plateau. There have not been any investigations into the current status of the glacier resources in the Park so far. This study reported the first summary of the glaciers in the Park at present and their variations since the 1960s. The data used here come from the two Chinese Glacier Inventories finished during 1969–1970 and 2006–2010, respectively, and the remote-sensing images during 1985–1990, 1995–2000 and 2018. The total glacier area in the Park is 772 km2 to our best estimate, much less than 2342 km2 reported in the first Chinese Glacier Inventory published in 2009. The shrinkage rate of the glaciers in the Yangtze River Park (a sub-park) had slowed from −0.37% per year during the 1970s to −0.09% per year during 2002–2012 in area, while that in the Lancang River Park had sped up from −0.34% per year during 1968–2000 to −0.67% per year during 2000–2018. There are no glaciers in the Yellow River Park (a sub-park). The change in the glaciers was related to the regional relatively rapidly warming and insufficient mass supply from precipitation. The geographic features of the glaciers in the Yangtze and Lancang Parks also lead to their different change extents, most of which happened at 5500 m a.s.l. and below.