The Spatial and Temporal Behavior of the Mixed Layer in Israel

Abstract

A detailed study to determine the spatial and temporal behavior of the coastal and inland mixed layer in Israel was undertaken. Over 300 upper air measurements (minisonde and airplane) from the central and southern parts of Israel were compiled and analyzed utilizing a statistical methodology developed for this purpose. The degree to which the upper air measurements taken at the permanent site at Beit Dagan represent five satellite sites in the central and southern part of the country was established. It was found that in cases of unstable atmospheric conditions accompanied by strong winds, the spatial correlation was higher than in cases of weak surface pressure gradients and stable atmospheric conditions. Significant differences in the mixing depth values were found for all synoptic categories at the permanent site, whereas the satellite sites exhibited significant differences only for the two most frequent summer synoptic conditions. The inland variance of the thickness of the mixed layer over complex terrain did not show a parabolic profile as suggested by other investigators for a flat terrain on theoretical and experimental grounds. For the rough terrain dealt with in this work, the top of the mixed layer tends to rise at a slower rate than the rise in the topographical relief; thus the thickness of the mixed layer decreases with the distance from the shoreline.