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The 1996–97 South-West Indian Ocean cyclone season was the longest on record, with both an unusually early start and unusually late ending. Most activity was from November through February. According to the Météo-France office (MFR) at Réunion, there were 21 tropical disturbances, 14 of which intensified into tropical depressions. There were 12 named storms, beginning with Antoinette and proceeding sequentially until Lisette. In addition, the Joint Typhoon Warning Center also warned on storms in the region, which identified five other tropical storms. Five of the storms attained tropical cyclone status, or with 10–minute maximum sustained winds of at least 120 km/h (75 mph); of these, three strengthened further into intense tropical cyclones, with Daniella and Helinda tied for strongest storm of the season. In August, a tropical depression developed in the south-west Indian Ocean for the first time 27 years, and a month later, a rare September tropical disturbance formed. The first named storm, Antoinette, was the first of several to originate in the neighboring Australian basin, or east of 90° E; the subsequent two named storms also formed in the Australian region. In early December, Cyclone Daniella likely developed out of the remnants of previous Tropical Storm Chantelle. After reaching peak 10–minute winds of 185 km/h (115 mph), Daniella weakened and passed just southwest of Mauritius; there, the storm left heavy crop damage and indirectly caused three deaths. In early January, Tropical Storm Fabriola was the first in a succession of three storms to move over Madagascar. The next – Cyclone Gretelle – killed 152 people when it struck southeastern Madagascar. Between January and February, Cyclone Pancho-Helinda lasted about 20 days between both the Australian and south-west Indian basins. Also in February, Tropical Storm Josie killed 36 people in western Madagascar after causing severe flooding. The final named storm was Tropical Storm Lisette, which dissipated on March 3 after striking Mozambique, killing three people. Despite the early end to the named storms, there were two additional disturbances, one of which became the first July tropical depression in 25 years. ==Season summary== During the season, the Météo-France office (MFR) based on Réunion island issued warnings in tropical cyclones within the basin, as part of its role as a Regional Specialized Meteorological Center. The agency estimated intensities via the Dvorak technique, which uses images from two satellites by the American National Oceanic and Atmospheric Administration. On certain days, the satellites had limited coverage in the eastern portion of the region, which limited warning capability.〔 At the time, the MFR issued warnings on tropical cyclones in the Indian Ocean from the coast of Africa to 90° E, south of the equator.〔 The Joint Typhoon Warning Center – a joint United States Navy – United States Air Force task force – also issued tropical cyclone warnings for the region.〔 Wind estimates from Météo-France and most other basins throughout the world are sustained over 10 minutes, while estimates from the United States-based Joint Typhoon Warning Center are sustained over 1 minute. 10 minute winds are about 1.14 times the amount of 1 minute winds. The MFR named storms from a sequential list provided by the nation of Seychelles, beginning with Antoinette. In addition to the named storms in the year, the list included Maryse, Nelda, Ocline, Phyllis, Rolina, Sheryl, Thelma, Venyda, Wiltina, and Yolette. The season was active, about 50% above normal, and was the fourth consecutive above-normal season. There was a total of 100 days on which disturbances, depressions, storms, or cyclones were active, compared to the average of 68. There were 12 named storms, above the normal of 9. Five intensified into tropical cyclones, also above the normal of 4. The season was the longest on record, with the first depression in August 1996 and the final depression in July 1997. Despite the long season, there was minimal activity from March to May, which usually represents about 25% of total activity. In addition, February was relatively quiet despite being the climatological peak. Majority of the storms developed in the northeast portion of the basin, and the storms took a variety of tracks during their durations.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「1996–97 South-West Indian Ocean cyclone season」の詳細全文を読む スポンサード リンク
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