Impact Of Subsurface Soil Temperature Variable On Surface Air Temperature Variability

In recent years,with the increase of global temperature,the influence on human life is becoming more and more serious,and the cause of the rising atmospheric temperature is drawing more and more attention,whereas most studies now focus on the effects of atmospheric temperature in the ocean,and few studies have been done on the influence of soil on temperature.In this paper,the influence of subsurface soil on atmospheric temperature near the ground is discussed.The results show that the change of subsurface soil temperature has an important effect on the change of n atmospheric temperature near the ground.Based on the actual observation data,analysis the correlation between subsurface soil temperature and atmospheric temperature near the ground by means of regression analysis,joint empirical orthogonal functions(Empirical Orthogonal Function,EOF)and time delay correlation analysis,etc.On this basis,using MPAS(Model for Prediction Across Scales,MPAS)to do sensitivity experiments,numerical simulation experiments were conducted to analyze the influence of subsurface soil temperature change on atmospheric temperature near the ground,and studied its possible mechanism.The main contents and conclusions are as follows:1)The correlation analysis results of subsurface soil temperature and atmospheric temperature near the ground suggest that: In the past thirty years,subsurface soil temperature was oscillating changes,but the general trend is that subsurface soil temperature is increasing,and the average winter temperature is higher than that of summer mean temperature.From the spatial distribution point of view,subsurface soil temperature increases from north and south poles to equator,and shows zonal distribution.Similarly,atmospheric temperature near the ground has risen in the past thirty years.From the analysis results of the dimensional time of the temperature anomaly,the warming range of the north and south poles is larger than that of the middle and lower latitudes.From the correlation analysis,it can be found that the subsurface soil temperature is closely related to the atmospheric temperature near the ground: The lead lag correlation analysis indicates that the subsurface soil temperature had the strongest correlation with the near surface atmospheric temperature in that month;The regression analysis indicates that the increase of subsurface soil temperature will be accompanied by the increase of atmospheric temperature near the ground;The joint EOF analysis indicates that the surface soil temperature in most parts of the world is consistent with the spatial distribution pattern of atmospheric temperature near the ground.2)The results of numerical simulation experiment indicate: The MPAS-A(The Model for Prediction Across Scales—Atmosphere)model has better simulation effect on atmospheric temperature near the ground,and it can well simulate the globaldistribution of atmospheric temperature near the ground,but it is less effective in individual regions.For example,in the winter,in the Elizabeth Queen Islands,Greenland and Russia and other areas close to the Arctic,the simulation effect of the model is poor;In summer,the model is less effective in simulating near surface atmospheric temperature near the equator.From the analysis of the sensitivity of the experimental results,it can be found that the change of subsurface soil temperature has a very important influence on the atmospheric temperature change in the near surface.Generally speaking,in most areas,changes in subsurface soil temperature lead to changes in atmospheric temperature near the ground surface,but in some areas atmospheric temperature near the ground changes very little,or can even be neglected.In winter,when the subsurface soil temperature increases a certain value,most of the world's atmospheric temperature near the ground will rise,but different regions have different effects,In the central part of South America,northern Asia,northern Africa,Central Europe and Australia,the atmospheric temperature near the ground rises most;In summer,when the sub-surface soil temperature rises a certain value,the atmospheric temperature near the ground rises is the biggest in northern Europe;When the surface soil temperature decreases,the subsurface atmospheric temperature in winter decreases in most areas,and the decreases in the northern part of North America,northern Asia and the northern part of Australia are the most.When the surface soil temperature decreases,the summer subsurface atmospheric temperature is generally decreases,and the decreases in the central region of North America and the northeastern region of Asia are the most.Also in some tropical regions and high latitudes,subsurface temperatures change little.