This paper introduces the surface energy balance system (SEBS) and its application for spatial-temporal estimation of actual evaporation using remote sensing data. Two case studies are presented, one for a large inland basin, the Urumqi River Basin, in Northwest China and the other for the whole Netherlands. After the presentation of the theory and processing procedures, NOAA/AVHRR scenes are used to derive land surface parameters as the inputs of SEBS. The HANTS (harmonic analysis of time series) algorithm is then used for reconstructing regional and temporal monthly and annual evaporation over the study areas. Time series of evaporative fraction and actual evaporation are successfully reconstructed for the two study areas and the estimated values are verified with the in-situ data. The results of this study demonstrate that SEBS algorithm can be used for spatial-temporal estimation of actual evaporation with an acceptable accuracy.

Pulse position coding for improving Doppler measurement by pulsed radar with respect to Woodward's expression of Doppler ambiguity is presented. The code of pulse positions is shown to be analytically obtained from the difference between the required ambiguity expression and that of a constant pulse-repetition frequency signal. One feature of the development is the possibility of codes for reducing the spurious peaks that are encountered in the usual ambiguity expression. This is accomplished by an approximation approach using delta functions.