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Fig. 3 presents the time series of water level for eight large TP lakes from Hydroweb and DAHITI data archives from the 1990s to 2018. All of the eight lakes showed rapid water level increase since around 2000. In comparison, the abrupt changing points varied with different lakes. For example, the lake level for Seling Co, Nam Co, Nganze Co and Tangra YumCo began to rise rapidly before 2000, while Migriggyangzham Co and Qinghai Lake began to grow rapidly after 2003 and 2005, respectively. The most dramatic expansion occurred in Seling Co in Central Tibet. From May 1998 to December 2010, the lake level for Seling Co rose from 4533.66 m to 4543.77 m, with an increasing rate exceeding 0.80 m/a. However, for these lakes, the increasing trends became weaker or even reversed after 2010. The findings were consistent with other previous studies (Hwang et al. 2019; Jiang et al. 2017; Lei et al. 2019; Song et al. 2015b; Yao et al. 2018). However, the lake levels for some lakes, such as Qinghai Lake, Zhari NamCo, Tangra Yumco, Ngangze Co and Migriggyangzham Co, began to increase significantly again after 2016. Among them, the abrupt rise of Zhari NamCo was the most remarkable, with a water level increase during 2016-2018 more than the total during the earlier 16 years (2000-2016). In contrast, the lake level for Nam Co showed inter-annual fluctuations without an evident trend during the recent several years. Level time series of other lakes are provided in the Supplementary Material (Fig. S1).