Intertropical Convergence Zone Intertropical Convergence Zone The Intertropical Convergence Zone (ITCZ), known by sailors as the doldrums or the calms, is the area encircling Earth near the Equator, where the northeast and southeast trade winds converge. The ITCZ was originally identified from the 1920s to the 1940s as the "Intertropical Front" ("ITF"), but after the recognition in the 1940s and the 1950s of the significance of wind field convergence in tropical weather production, the term "ITCZ" was then applied. When it lies near the Equator, it is called the near-equatorial trough. Where the ITCZ is drawn into and merges with a monsoonal circulation,
Climate of the United Kingdom United Kingdom lasts from September to November. The season may be a little more unsettled; as cool polar air moves southwards, it can meet warm air from the tropics and produce an area of disturbance along which the country lies. This can combine with the warm ocean due to heating throughout the spring and summer, to produce some unsettled weather. In addition, the land may become colder than the ocean, resulting in significant amounts of condensation and rain-bearing clouds. Atlantic depressions at this time can become intense, and winds of hurricane force (greater than ) can be recorded. Western areas,