The Tibetan Plateau (TP) plays a significant role in the Earth's climate system. This letter examines the nighttime lake surface water temperature (LSWT) of 374 lakes (≥10 km 2 each) over the TP for the past 15 years (2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015). An overall warming trend (0.037°C/year) is found and it is consistent with the warming air temperature (0.036°C/year) over the TP, with the vast majority of the lakes (70%, with 28% of which are significant) showing warming (0.076°C/year) and the rest (30%, with 37% of which are significant) showing cooling (À0.053°C/year). This astonishing contrast was controlled by different water sources recharging these lakes: (1) warming LSWT due to increased precipitation (central and northern TP) or permafrost degradation (northwestern TP) and (2) cooling LSWT due to increased glacier meltwater (southwestern TP), revealing LSWT a sensitive indicator to climate change that triggered different regional responses in precipitation, permafrost, and glacier changes over the TP. This study helps improve our understanding of high-altitude lakes and their changing mechanisms under the warming climate.
Plain Language SummaryThe Tibetan Plateau (TP), a vast highland area in Asia, plays a significant role in the Earth's climate system. Here we examine the nighttime lake surface water temperature (LSWT) of 374 TP lakes (≥10 km 2 each) over the past 15 years (2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015). An overall warmin trend (0.037°C/year), consistent with the warming air temperature (0.036°C/year) over the TP, is found, with the vast majority of the lakes (70%) showing fast warming (0.076°C/year) and the rest (30%) showing fast cooling (À0.053°C/year). This astonishing contrast was controlled by different water sources recharging these lakes:(1) warming LSWT due to increased precipitation (central and northern TP) or permafrost degradation (northwestern TP) and (2) cooling LSWT due to increased glacier meltwater (southwestern TP). Although there are clear regional differences in precipitation, permafrost degradation, and glacier melt, these changes were all due to the warming air temperature over the TP. This study reveals that LSWT is a sensitive indicator of the climate change that triggered different regional responses in precipitation, permafrost, and glacier changes over the TP. This study helps improve our understanding of high-altitude lakes and their changing mechanisms under the warming climate. 2012 (IPCC, 2014;Zhang et al., 2015).Lakes are an important part of the landscape on the TP. There are more than 1,100 alpine lakes (≥1 km 2 each) over the TP with the total area exceeding 46,527 km 2 (Wan et al., 2016). Lakes serve as an excellent indicator of climate change since they hold a large majority of Earth's liquid freshwater, which supports the enormous WAN ET AL. 11,177
Geophysical Research Letters
RESEARCH LETTER
10.1029/2018GL078601Key Points:• Lake surface water tempera...
