The Concept of the Subtropical Depression and its Effect on the Climate of the Mediterranean Sea and Iraq

Abstract

This research paper focuses on a very important topic in the synoptic climate which is subtropical depression that is considered as a type of hybrid cyclone which is characterized with common features of both frontal cyclone and tropical storms. The subtropical depressions are formed on warm waters within extra tropical cyclone latitude. The most important feature of these subtropical depressions is that their original development is from the frontal depressions in their last stages (occluded stage). Moreover, the 23Co degree of the sea surface is very suitable to form the subtropical depressions, which have a clear eye storm and a range of spiral form clouds with strong winds. The researchers had made clear that these depressions are formed when cold air progresses towards the warm waters of the sea which are accompanied with cut- off low and deep trough in the upper air. The Mediterranean’s warm water helps to form these depressions but with low frequency. The favorite area to form these depressions is the middle part of the sea. The effect of this depression on Iraq is very rare because of two reasons. The first reason is the low frequency of the depression on the Mediterranean Sea. Second, this depression is formed in an area far from Iraq, especially in the middle parts of the Mediterranean Sea.