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Typhoon Pamela was a powerful typhoon that struck the U.S. territory of Guam in May 1976, causing about $500 million in damage (USD). The sixth named storm and third typhoon of the 1976 Pacific typhoon season, Pamela developed on May 14 from a trough in the Federated States of Micronesia in the area of the Nomoi Islands. It executed a counterclockwise loop and slowly intensified, bringing heavy rains to the islands in the region. Ten people died on Chuuk due to a landslide. After beginning a steady northwest motion toward Guam, Pamela attained its peak winds of 240 km/h (150 mph). On May 21, the large eye of the typhoon crossed Guam, producing typhoon-force winds (greater than 118 km/h or 73 mph) for a period of 18 hours. An estimated 80% of the buildings on the island were damaged to some degree, including 3,300 houses that were destroyed. Pamela's slow motion produced 856 mm (33.7 in) of rainfall, making May 1976 the wettest on record in Guam. Despite the high damage, well-executed warnings kept the death toll to only one. After affecting the island, the typhoon weakened and turned northeastward, passing near Iwo Jima before becoming an extratropical cyclone. ==Meteorological history== The origins of Typhoon Pamela were from a tropical disturbance that persisted in the eastern end of the equatorial trough on May 13. At the time, it was located about 425 km (265 mi) north of Chuuk in the Federated States of Micronesia. The disturbance was initially difficult to locate as it tracked generally to the south and southwest, a motion caused by a southward-moving tropical upper tropospheric trough.〔 On May 14, the Japan Meteorological Agency (JMA) indicated that the system developed into a tropical cyclone.〔 That same day, the Joint Typhoon Warning Center (JTWC) followed suit and classified it as Tropical Depression 06W. The next day, data from the Typhoon Chasers indicated that the depression intensified into Tropical Storm Pamela. It was able to intensify after the trough receded northward, developing outflow. The storm turned to the south and east, gradually executing a counterclockwise loop through the FSM. This was due to a building ridge between Pamela and Typhoon Olga to its west. On May 16, observations from Satawan in the Caroline Islands indicated that Pamela attained typhoon status, which is a tropical cyclone with maximum sustained winds of at least 118 km/h (74 mph). This was confirmed the next day by the Typhoon Chasers. Upon attaining typhoon status, Pamela was a small tropical cyclone with a central dense overcast spanning 280 km (175 mi) in diameter. After completing its counterclockwise loop, the typhoon began a slow motion to the northwest, once the ridge to its west diminished. On May 18, it passed within 95 km (60 mi) of Chuuk, and around that time Pamela developed a circular eye about 18 km (12 mi) in diameter. The typhoon steadily intensified as it began a more steady northwest movement due to a ridge to its east, and on May 19 Pamela attained peak winds of 240 km/h (150 mph) about 485 km (300 mi) southeast of Guam. At that time, it had gusts to 295 km/h (185 mph).〔 Typhoon Pamela maintained peak intensity for about 18 hours, during which the Typhoon Chasers reported an atmospheric pressure of ; the aircraft also reported concentric eyewalls.〔 The JMA estimated the minimum pressure was slightly lower at .〔 A trough passing to its north caused the typhoon to turn more to the north-northwest. Around 0400 UTC on May 21, the eyewall of Pamela struck southeastern Guam with winds of about 220 km/h (140 mph). Over a three-hour period, the 37 km (23 mi) wide eye crossed the island. After leaving the island, Pamela continued steadily northwestward for two days while maintaining its intensity. On May 23, it turned to the north and northeast due to a break in the subtropical ridge. The typhoon passed 28 km (17 mi) east of Iwo Jima with winds of 140 km/h (85 mph). As Pamela accelerated over cooler waters and into an area of higher wind shear, it rapidly weakened and was downgraded to a tropical storm on May 25. The next day, the storm became extratropical,〔 which lasted until June 1 before dissipating over the Bering Sea. 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「Typhoon Pamela (1976)」の詳細全文を読む スポンサード リンク
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