Only in the Americas are tropical storms called hurricanes. In east Asia, the storms are often called typhoons , a word from the Malay language. Elsewhere, tropical storms are called tropical cyclones , and this is the term used by scientists. Cyclones can be huge, like the 1000-mile wide storms common in winter, or small, like tornados. Weaker tropical cyclones are called tropical depressions .
Tropical cyclones form over all the world's tropical oceans except the South Atlantic.
The number of storms in each region varies considerably from year to year, as we know from our experience with the North Atlantic, but a good year in one region is often a bad year in another. The totals for each hemisphere don't vary as much. The chart shows Northern Hemisphere storms by year and region from 1994 through 1998. As the chart also reveals, the Northwest Pacific has by far the largest number of tropical cyclones. Northern Hemisphere storm activity peaks in late summer and early fall, as we know.