Study Of Parameterization Scheme On Regional Average Water And Thermal Flux Over Heterogeneous Land-Surface

The land-atmosphere interactions attract interest from climate modeling during the decades. Soil texture and vegetation canopy have a significant effect on regional atmospheric circulations. Natural land characteristics are multiple scales heterogeneity. It is very important that studies further schemes of heterogeneous land surface. But it is well known that data of land surface process is rare. Remote sensing techniques have demonstrated their potential for measurements of soil temperature, vegetation canopy and so on. However, What is very difficult that uses reasonably both remote sensing data and ground data in calculating the energy, mass .radiation and momentum exchanges at land-atmosphere interactions, let alone apply in practical works.In this paper, On the basis of observed data, spatial-temporal variation characteristics of soil temperature and soil moisture . Soil temperature effects on soil water movement are studied for several kinds of typical underlying surface by using statistics ,spectrum,filtering wave methods. And then, a example is given about calculating regional average water mass and thermal flux exchanges at land-atmosphere interactions in Yangtze river lower by a statistical-dynamical approach through combining remote sensing data with ground measurement data.The results show that: (1) soil moisture follows a β-distribution over the discussed zone of the humid area in Summer, but do distribution at the researched zone vicinity of oasis desert area in Winter. There is a period of soil contents range from ten to twenty five days over the humid discussed area in Summer, and the period is not obvious at the discussed zone of close oasis desert area in Summer and winter.(2) soil temperature exits several periodic variations of different depths ranging from six to twenty four days in Heihe region, and nine to thirty days in Gaize and Shiquanhe region. It also shows that gradient of soil temperature affects on the soil content movement more greatly in summer. (3) The land surface temperature of Yangtze River lower region is retrieved from NOAA-AHVRR data. It shows that the surfacetemperature is extremely sensitive to land surface characteristics. A PDF of land surface temperature is given that is used in calculating sensible heat flux and latent heat flux of Yangtze River lower region. The result of numerical experiments shows that this scheme is practical.