Western North Pacific, North Indian Ocean, and Southern Hemisphere Tropical Cyclones of 1997

Abstract

This paper is an annual summary of the western North Pacific, north Indian Ocean, and Southern Hemisphere tropical cyclones of 1997. (Note: for the Southern Hemisphere, the 1997 annual total is accrued from July 1996 to June 1997.) The tropical cyclone statistics presented are derived from records at the Joint Typhoon Warning Center (JTWC), Guam. Although the text focuses on the tropical cyclones that occurred in the western North Pacific during 1997, it also includes brief summaries of the tropical cyclones in the north Indian Ocean, south Indian Ocean, and the South Pacific. The 38 tropical cyclones in the Southern Hemisphere during 1997 were a record high, and the 23 typhoons in the western North Pacific were second only to the 24 typhoons there in 1971. In the north Indian Ocean, the annual number of tropical cyclones was below normal. The large-scale circulation anomalies, and many aspects of the tropical cyclone distribution, were those typical of a major El Niño. Highlights of the 1997 tropical cyclone distribution in the western North Pacific also include an unprecedented number of very intense tropical cyclones?11 became supertyphoons?and a large eastward displacement of the genesis locations.