蒸発散の時・空間平均化手法開発に関する検討

Abstract

Ordinarily, the hydrological data that we can obtain are not continuous data over space and over time.So, when we try to estimate daily evapotranspiration, we must use some techniques to average the data.In the present paper, to develop the techniques mentioned above, some considerations are carried out.For considerations some numerical simulations are carried out.By the objects, time scale, and spacial scale, different numerical models were used.The main results are as follows.1) Daily evapotranspiration was closely related to the wind speed averaged over the day for water surface, and was related to the average wind speed influenced by the radiation for land surface.2) The technique to average over time using remote-sensing data was developed. Basic concept of this technique is iterative calculations by force restore method.