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Typhoon Longwang, known in the Philippines as Typhoon Maring, was the deadliest tropical cyclone to impact China during the 2005 Pacific typhoon season. Longwang was first identified as a tropical depression on September 25 north of the Mariana Islands. Moving along a general westward track, the system quickly intensified and reached typhoon status on September 27. After reaching Category 4-equivalent intensity on the Saffir–Simpson hurricane scale, adverse atmospheric conditions along with internal structural changes resulted in temporary weakening. The structural change culminated in Longwang becoming an annular typhoon and prompted re-intensification. The storm attained peak strength with winds of 175 km/h (110 mph) and a pressure of 930 mbar (hPa; 27.46 inHg) on October 1 as it approached Taiwan. Interaction with the mountainous terrain of the island and further structural changes caused some weakening before the typhoon made landfall near Hualien City early on October 2. Crossing the island in six hours, Longwang emerged over the Taiwan Strait before moving onshore again later that day, this time in Fujian Province, China as a minimal typhoon. Once over mainland China, the storm quickly weakened and ultimately dissipated late on October 3. Prior to the storm's arrival, officials in Taiwan activated all emergency operations centers and urged residents to take serious precautions. The storm brought record-breaking winds, peaking at in Hualien City, and torrential rains. Despite the intensity of the storm, damage was relatively limited there. Two people lost their lives, 73 were injured, and damage reached NT$570 million (US$17.7 million). Large-scale evacuations took place in mainland China, with 684,860 people relocating. Losses were extensive in Fujian Province where 1-in-100 year rains caused disastrous flooding in Fuzhou, killing 62 people. In Minhou County, 85 paramilitary police perished when a landslide destroyed their barracks. Throughout China, 147 people were killed and damage amounted to 7.81 billion RMB (US$944.6 million). Due to the severe damage, the name ''Longwang'' was later retired. ==Meteorological history== On September 24, 2005, the Joint Typhoon Warning Center (JTWC) began monitoring a tropical disturbance a tropical disturbance north of the Mariana Islands. Convective banding features soon consolidated around a low pressure area associated with the system, prompting the issuance of a Tropical Cyclone Formation Alert the following day. Later on September 25, the Japan Meteorological Agency (JMA) declared the system a tropical depression. Situated in a region characterized by low wind shear and favorable upper-level divergence, steady intensification ensued.〔 Early on September 26, the JTWC also classified the system as a tropical depression, designating it as ''19W''. Hours later, both agencies assessed sustained winds to have reached 65 km/h (40 mph), indicating tropical storm intensity. As such, the JMA named the storm ''Longwang''. Situated to the southwest of a ridge, the storm tracked slowly west-northwest, while strengthening at an increasing rate. A temporary turn northwest occurred on September 26 as Longwang approached a weakness in the ridge which had previously steered it west-northwestward.〔 In the 24 hours following the storm's naming, Longwang quickly intensified into a typhoon.〔 Once at typhoon status, the storm resumed a more westerly track as a second ridge extending from eastern Asia became the dominant steering factor.〔 On a westerly course toward Taiwan and eastern China, Longwang underwent a period of rapid intensification from September 27–28.〔 At the end of this phase, the JMA assessed peak winds at 155 km/h (100 mph) while the JTWC rated it as a Category 4-equivalent typhoon on the Saffir–Simpson hurricane scale.〔〔 On September 29, the Philippine Atmospheric, Geophysical and Astronomical Services Administration assigned the typhoon the local name ''Maring'' as it entered their area of responsibility.〔 The following day, Longwang underwent a structural change, transitioning from asymmetrical banding to symmetrical, making it an annular tropical cyclone. During the transition, upper-level divergence and outflow significantly decreased, resulting in temporary weakening of the typhoon. Additionally, an increase in westerly wind shear caused the interior structure to become asymmetric, with a southwest to northeast tilt noted by dropsondes released by the Dropwinsonde Observations for Typhoon Surveillance project.〔 Once the transition into an annular cyclone completed,〔 Longwang re-intensified and attained its peak intensity on October 1 while situated 400 km (250 mi) south of Okinawa. The JMA assessed winds at 175 km/h (110 mph) along with a barometric pressure of 930 mbar (hPa; 27.46 inHg).〔 The JTWC estimated Longwang to have been slightly stronger, with one-minute sustained winds of 230 km/h (145 mph).〔 At the time of peak intensity, an unmanned weather reconnaissance vehicle, known as Aerosonde, was flown into the typhoon and recorded peak winds of at an altitude of . As the storm approached Taiwan late on October 1, an eyewall replacement cycle began, with a large secondary eyewall forming around the inner one. At 1848 UTC, Doppler weather radar velocity estimates indicated winds of 240 km/h (145 mph) at an altitude of . An interpolated surface pressure of 924.5 mb (hPa; 27.30 inHg) was obtained based on data from the Aerosonde. After flying in the storm for ten hours, the unmanned vehicle encountered severe turbulence and crashed about east of Taitung City. Interaction with the mountainous terrain of Taiwan caused Longwang to weaken somewhat.〔 The system ultimately made landfall near Hualien City at 0500 UTC on October 2. Just six hours after moving inland, Longwang emerged over the Taiwan Strait with its circulation mostly intact; however, weakening continued as it approached eastern China. Remaining over water for less than 12 hours, the typhoon made its second and ultimate landfall in Fujian Province late on October 2.〔 The storm quickly degraded over the following day, with winds decreasing below gale-force within 12 hours. The former typhoon slowed and turned northward over western Fujian before dissipating late on October 3.〔〔 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 Longwang」の詳細全文を読む スポンサード リンク
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