| The lake, the special element of nature, is called the indicator of the global climate changes, and its expanding,contracting and disappearing can truly reflect the climate and environmental changes. Tibetan Plateau(TP), known as the ―Water Tower of Asia‖ and ―The Third Pole,‖ is highly relevant to global climate dynamics changes. TP has the largest number of alpine lakes in the world in nature state which have no influence of artificial disturbance, therefore, the changes of those lake and area levels could keep a clear record of lake variation in TP. Those variations are internal connected with climate changes and glacier retreat. To reveal the dynamic lake variation of the inland lake in TP, we would facilitate understanding of regional responses to climate changes under global warming in recent decades.The changes of lakes are mainly influenced by meteorological conditions, such as precipitation, evapotranspiration,temperature, and recharge types of basin. The different climate zones could cause the various changes of lakes. The meteorological station are of scarcity and uneven distribution in TP, and some lakes even have no stations. Rapidly development of remote sensing technologies provide powerful support for the research on TP, which opens a good way to further understanding the processes and extent of lake s and its response to global climate changes.This paper focuses six basins, Namco basin, Zhari Namco basin, Taro Co basin, Pumo Yumco basin, Mapang Yumco basin and Peiku Basin, which are all situated in south-central of TP, multi-source remote sensing data and products are sufficiently exploited to obtain the time- series of the six typical lakes area and level from 1972 to 2012, and analyzed the variation in recent 40 years. In addition, This paper also simulated TP evapotranspiration by SEBS from 2001 to 2010. The evapotranspiration results, combined with temperature and precipitation, are used to explain the dynamics changes from the aspect of water balance,and discuss the hydrologic environment changes and their relationship with climate changes. The main results are follows:(1) From 1972 to 2012, the four inland lakes(Namco, Pumo Yumco, Zhari Namco, Taro Co) have expanded by 80.68 km2、6.62 km2、36.97km2、3.63 km2 in lake area, respectively,while the two lakes(Mapang Yumco, Peiku Co,) have contracted by 5.36km2,9.46km2, On the whole, the lakes area of Namco and Pumo Yumco present increasing tendency, Mapang Yumco and Peiku Co decreasing, while the lakes area of Zhari Namco and Taro Co are decreased gradually and then increased;(2) In 1972-2012, The lake level change ratio of Namco(1995-2010), Pumo Yumco(2003-2014), Zhari Namco(1992-2014), Taro Co(2003-2014), Mapang Yumco(2002-2010), Peiku Co(2003-2008) are 0.274m/a、-0.011m/a、0.039m/a、0.089m/a、-0.135m/a,-0.169m/a, respectively;(3) In 40 years, the trend of temperature in each basin is remarkably increased; the trend of precipitation in Namco basin, Zhari Namco basin and Taro Co basin are increased, while Pumo Yumco basin, Peiku Co basin and Mapang Yumco basin are decreased, In 2001-2010, the evapotranspiration of Namco basin, Pumo Yumco basin,Peiku Co basin and Mapang Yumco basin went up, while Zhari Namco basin and Taro Co basin went down;(4) Because the discharge is mainly from the runoff formed by snow meltwater and permafrost, the rainfall and evapotranspiration of Namco basin, Pumo Yumco basin has grown, the same as the lake level and area; while the Zhari Namco basin and Taro Co basin are discharged by rainfall, the lake level and area are grown up; The main reason of Peiku Co basin and Mapang Yumco basin, located in south fringe of TP, may be the fewer discharge and rainfall, with the evapotranspiration increased... |
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