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Cyclone Bonita in January 1996 struck both Madagascar and Mozambique, causing severe damage. The long-lived storm began developing in the last hours of 1995, and slowly consolidated over the open waters of the South-West Indian Ocean. Tracking generally toward the west-southwest, the disturbance received its name from Météo-France on January 5. Ultimately peaking as an intense tropical cyclone, Bonita bypassed Mauritius and Réunion to the north before striking northeastern Madagascar late on January 10. There, the storm affected up to 150,000 people, flooded wide tracts of croplands, and killed 25 people. In the aftermath, disaster relief came from both the government of Madagascar and the international community, as well as non-governmental organizations (NGOs); the United Nations Department of Humanitarian Affairs assisted in the distribution of about $450,000 in monetary donations. Bonita emerged into the Mozambique Channel as a significantly diminished storm, though it quickly regained some of its previous intensity. Three days after its initial landfall, the cyclone moved ashore over the Zambezia Province of Mozambique. Throughout northern parts of the country, Bonita triggered extensive flooding that damaged or destroyed hundreds of buildings and reportedly killed 17 individuals. Swollen rivers submerged roads and bridges, isolating some locations. A meteorological rarity, Bonita continued inland for several days, persisting as a distinct tropical low; the system traversed southern Africa and ultimately entered the South Atlantic Ocean. In the process, it dropped unseasonably heavy rainfall over Zimbabwe and Zamibia. A paper published by the Zambia Meteorological Department asserted that Bonita was the first storm confirmed to have tracked across the African continent from the South-West Indian Ocean to the Southern Atlantic Ocean. ==Meteorological history== Cyclone Bonita originated from a weak area of disturbed weather observed about to the east of Diego Garcia, in the Chagos Archipelago, on December 31, 1995. The system was marked by a distinct low-level circulation and curved banding features,〔Le Goff, et al., p. 24〕 and the Joint Typhoon Warning Center (JTWC) promptly began monitoring it. A hostile upper-air pattern prevented further organization over the following several days as the disturbance drifted generally toward the southwest. On January 3, the low pressure center showed initial signs of strengthening,〔 prompting Météo-France to declare it a tropical disturbance, the lowest of seven distinct intensity categories used by the agency. The surrounding environment became more favorable for tropical cyclogenesis, with increased upper-level divergence, and consequently, the system further matured;〔 it was upgraded to a depression early on January 5, and to a moderate tropical storm 12 hours later.〔 At that time, it was named Bonita.〔Le Goff, et al., p. 25〕 The JTWC upgraded 06S (its internal designation for Bonita) to a tropical storm equivalent early the next day.〔 Continuing to intensify, the storm accelerated toward the west-southwest, heading nearly due west for a short time as it encountered a subtropical ridge of high pressure. The cyclone's inner structure steadily improved in organization, adhering well to the model of a well-developed tropical system. Transcending the severe tropical cyclone stage,〔 Bonita achieved tropical cyclone status at 1200 UTC on January 8.〔 Passing just south of St. Brandon, the system exhibited a broad and ill-defined eye about 50 km (30 mi) across.〔 The cyclone quickly strengthened over the course of January 8, with a consolidating eye and a formidable central dense overcast. Tracking about north of Mauritius, Bonita reached its peak intensity—as assessed by Météo-France—with maximum sustained winds of 185 km/h (115 mph) and a central barometric air pressure of . This ranked the storm as an intense tropical cyclone, the second-highest category on the regional scale.〔 The JTWC lists 06S as having peaked at 1200 UTC the next day, with 1-minute peak winds of 250 km/h (155 mph) (coinciding with strong Category 4 intensity on the Saffir–Simpson Hurricane Scale).〔 According to Météo-France, Bonita began to weaken slightly by early on January 9,〔〔 the eye becoming asymmetric and poorly defined. The ridge to the south prevented the storm from progressing to the south,〔 and after passing about 270 km (170 mi) north of Réunion, Bonita shifted due west and later roughly west-by-north, apparently steered by a building mid-to-upper-level anticyclone south of Madagascar.〔Le Goff, et al., pp. 25–26〕 It remained a strong tropical cyclone as it approached the eastern coast of Madagascar, making landfall near Mahavelona on the night of January 10 local time,〔 or about 2130 UTC. At the time of landfall, a clear eye was visible on satellite imagery.〔Le Goff, et al., p. 28〕 It crossed the island nation over the course of about a day, weakening significantly to a moderate tropical storm as it reemerged into the Mozambique Channel. Once over water, favorable conditions prompted quick reintensification of the cyclone, as it proceeded west-southwestward toward mainland Africa.〔Le Goff, et al., p. 26〕 At 1200 UTC on January 13, Bonita reattained severe tropical storm status, marking its secondary peak intensity with 10-minute winds of 95 km/h (60 mph).〔 With an expansive circulation and a good structure, the cyclone made its second and final landfall over the Zambezia Province of Mozambique, between Quelimane and Pebane District, on the night of January 13 local time. Bonita meandered inland, weakening only gradually and nearly tracking back over open water.〔 Although the cyclone's "best track" listings by both Météo-France and the JTWC end at 0600 UTC on January 15,〔〔 its residual tropical low remained distinct and active as it continued generally westward across the southern African continent. Where nearly all landfalling tropical cyclones in the area recurve toward the south or dissipate quickly on moving ashore, a rare synoptic pattern allowed the remnants of Bonita to persist, moving over northern Zimbabwe on January 16. For the next two days, the weakening storm remained prominent on satellite imagery, ultimately moving off the coast of Angola and entering the South Atlantic Ocean on January 19. By the next day, the system had succumbed to cold waters and days of land interaction, dissipating completely. According to a paper published by the Zambia Meteorological Department, Bonita was the first tropical cyclone known to have traversed southern Africa from the South-West Indian Ocean to the South Atlantic. 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「Cyclone Bonita」の詳細全文を読む スポンサード リンク
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