The Characteristic Of Lake Changeand Its Response To Climate In Qinghai-Tibet Plateau Under The Background Of Global Warming

In the context of global warming,as an important component of the plateau ecological environment,the Qinghai-Tibet Plateau lake can effectively reflect the characteristics of the plateau climate.In order to accurately analyze the climate change around the Qinghai-Tibet Plateau,the meteorological data selected in this paper are derived from the monthly data of annual average precipitation,annual average temperature,sunshine duration and wind speed of the ground from 68 basic meteorological stations in Tibet from 1995 to 2015,and are processed using the climatic tendency.The correlation between rate,cumulative anomaly,isoline distribution,wavelet period and meteorological elements are analyzed.The climatic change trend of Qinghai-Tibet Plateau in recent 20 years is clarified.Based on the Landsat satellite remote sensing data and the lake data provided by the Qinghai-Tibet Plateau Scientific data Center,the spatial and temporal differences,the characteristics of the plateau lake area changes in the plateau are analyzed.Based on the characteristics of climate change and lake area of Qinghai-Tibet Plateau,the correlation between them is analyzed scientifically.The typical lakes in Qinghai-Tibet Plateau are selected as a case study.The main conclusions of this paper are as following :(1)In the last 20 years,the annual average precipitation trend is decreasing,the annual average temperature trend is rising,the annual average wind speed trend is decreasing as a whole.The annual average precipitation in the eastern part of the plateau is the largest,and the increase of wind speed is also the largest.The climate in the whole region is warm and wet gale.The annual average precipitation is the largest in the southern part of the plateau,but the southern part is still the region with the most abundant precipitation over the whole plateau,and the increase of sunshine is also the largest.The climate in the whole region is the period when the wind speed decreases and the sunshine is sufficient and warm.The annual average temperature increase is the largest in the western part of the plateau,and the increase of precipitation is relatively small,the climate in the whole region is warm and wet sunshine is sufficient;the wind speed drop rate is the largest in the north of the plateau,and the sunshine decline rate is the largest.The whole region climate is the wind speed decrease,sunshine duration,warm and wet.The climate of Qinghai-Tibet Plateau is divided into two periods in the past 20 years.The precipitation of Qinghai-Tibet Plateau increased significantly from 1995 to 2004,and decreased from 2005 to 2005.The climatic characteristics of the first 10 years and the later 10 years are very different.(2)The total number of lakes in the Qinghai-Tibet Plateau increased 307 from 1995 to 2010,then decreased 52 from 2015 to 2015.It shows that from 1995 to 2010,the Qinghai-Tibet plateau lakes expansion for the overall trend.From 2010 to 2015,the overall trend is still expanding,but some lakes have shrunk.(3)The changes of the overall lake area of the Qinghai-Tibet Plateau and the lake area in different areas of the Qinghai-Tibet Plateau are all affected by climate change,among which precipitation and temperature are the main factors influencing the lakes.Precipitation will directly affect the lake water volume and area,a large area of the Qinghai-Tibet Plateau glacier frozen soil received the effect of temperature rise,resulting in glacial frozen soil melt water,thus the lake area increased as an indirect factor.According to the correlation analysis,it can be seen that the temperature has the greatest influence on the lake area of the whole Qinghai-Tibet Plateau.(4)The overall change of lake area in Qinghai Lake is first decreased and then increasing,and the changes of annual average precipitation and evaporation amount mainly affect the change of Qinghai Lake area.In the last 20 years,the lake area of Xilin dislocation showed a significant increasing trend,which increased rapidly first and then slowly,and the annual average temperature,snow days and sunshine hours were the main factors affecting the change of lake area.The area of Namuco Lake showed a certain trend of continuous expansion,which experienced two stages of first growth and then basic stagnation.The temperature and snow days around the lake were the main factors affecting the changes of lake area.