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,
Cave of the Winds (New York) and walkways. Tropical storm-like conditions can be experienced, as winds can reach up to 68 mph underneath the falls. The cave was obliterated in a massive 1954 rockfall and subsequent dynamiting of a dangerous overhang. Today, the "Cave of the Winds" is the name of a tourist attraction near the same site. An elevator takes people from the area between the American and Canadian Falls down to the level of the Niagara River at the base of the American Falls. A series of redwood decks and platforms allow sightseers to walk right up to the base of the Bridal Veil