The Tropical Climate Control. The most important climate control in regard to the tropical climate types relates to the position of the Inter Tropical Convergent Zone or ITCZ. The ITCZ is an area of low pressure and marks the point of trade wind convergence.he second distinctive climate feature of tropical regions is the dry season. As you can see from the diagram to the right of the Hadley circulation air rises above the ITCZ to create a low pressure zone, characterised by high humidity and rainfall. Further north and south of this zone air begins to sink.