Remote Sensing Analysis Of Global Typical Lakes Temperature Pattern Based On MODIS

Using the method of remote sensing to invert the temperature of the lake with its wide spatial coverage,frequent cycle and high precision has become an effective means to understand the changes of the ecological environment of the lake,Evolution and climate change are closely related,In this study,with the support of remote sensing and GIS technology,first 7682(167*46)tiles of 2015 MODIS land surface temperature(LST)product of level 3(MOD11A2)were used to investigate and analysis the global spatial pattern of lake water surface temperature(LWST)for 2446 lakes(>25km~2)with the area of 1.43*10~6km~2,and 46 typical lakes were selected around the world,covering 31740(46*15*46)Tiles image,get 46 lakes in 15 years the lake surface temperature trends.Through the lake surface temperature and measured data,meteorological site 0cm geothermal data and NOAA ground 2m temperature data fitting results can be seen,both the measured data or temperature data,and the lake surface temperature maintained a high degree of correlation.Therefore,it can be proved that MODIS data inversion of lake surface temperature is feasible.From the global lakes daytime,night and day and night temperature difference between the annual surface temperature pattern can be seen,On the whole,the LWST at global scale presented obvious latitudinal differentiation,i.e.aprogressively decreasing trend from equator to polar was demonstrated,from the coastal to the inland increase in the degree of longitude,The vertical distribution of the region to the high altitude region is consistent with the distribution of the temperature.The latitudinal differentiation rule and the vertical differentiation rule are the most obvious in the lake temperature pattern.However,the regional differences of air temperature,elevation,landuse/cover,and lake morphology exerted strong impact on the LWST variations comparing with lakes of same latitude.Thus,a detailed comparison and analysis of the differences between the 30 lakes temperatures in 5 typical region determined from different part of the world are carried out.Comprehensive analysis indicates that the pattern of air temperature is the dominant factor of LWST.Meanwhile,elevation is the other main factor influencing the LWST distribution pattern at regional scale.The results of four dimensions from lake latitude,climatic zone,elevation,land use show that are directly affected by the temperature indirectly affect lake surface water temperature,can explain the difference between temperature and water temperature differences are consistent.On the whole,the range of 46 typical lakes surface temperature increase and decrease between years(2001~2015)is generally distributed between-1.5?and 1.5?,and the few lakes increase and decrease in different years,and the trend of lake temperature is not consisitent,But in the northern hemisphere high latitudes of the lake,the temperature is generally on the rise,and located in the equator near the African region of several low latitude typical lakes,the temperature is generally in a downward trend.In recent decades,in the context of global warming,the mountain ice and snow melt water for the supply or ice age of the lake has a strong warming trend,water temperature and temperature changes are closely related.At the same time,the lake temperature response to altitude and lake area changes in response.The change of lake temperature is closely related to the evolution of natural ecological environment,and the influencing factors of lake temperature are the future work focus.