In-situ lake level observations on the western Tibetan Plateau

Lake level has been monitored at six lakes (Lumajiangdong Co, Memar Co, Jieze Caka, Longmu Co, Luotuo Lake, Aksaiqin Lake) on the western TP. HOBO water level loggers (U20-001-01) or Solist water level loggers were installed in the littoral zone of the lakes. To validate lake level changes, two HOBO water-level loggers were installed in different regions of Lumajiangdong Co (Fig. S1). Because water levels were recorded as changes in pressure (less than 0.5 cm water level equivalent), air pressure data were subtracted from the level loggers to obtain pressure changes related to water column variations. The loggers can still work efficiently at the beginning of ice cover. However, there is no data available when the lake ice was thick enough and loggers were frozen up. Daily lake-level changes were used in this study. At Lumajiangdong Co, lake level data are available between October 2016 and September 2021. At Memar Co, lake level data are only available between October 2017 and September 2019 and between October 2020 and September 2021. For Jieze Caka, Longmu Co and Luotuo Lake, there is only one year’s data available. Water depth of the loggers was measured during fieldwork to validate the logger data.