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Super-Typhoon RAMMASUN Crosses the Philippines and Southern China in July 2014 Dr

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Super-Typhoon RAMMASUN Crosses the Philippines and Southern China in July 2014 Dr Super-typhoon RAMMASUN crosses the Philippines and southern China in July 2014 Dr. Susanne Haeseler; updated: 22 July 2014 Introduction On 18 July, super-typhoon RAMMASUN crossed southeastern China (Fig. 1 and 2). The China Meteorological Administration assessed it as “the most violent typhoon landing in South China since 1973”. RAMMASUN raged in the Philippines just before. In the capital city Manila, which was affected by the typhoon, schools and airport were closed as a precaution- ary measure. There were power outages in the Philippines and also in southern China. RAMMASUN claimed numerous lives, more than 90 in the Philippines alone. Fig. 1: Satellite image of typhoon RAMMASUN over southeastern China, acquired on 18 July 2014, 05:35 UTC. [Source: NASA, Earth Observatory] 1 Fig. 2: Track of super-typhoon RAMMASUN across the Philippines and southern China in July 2014. The points show the position of the storm at 6-hour intervals; the colour repre- sents the maximum sustained wind speeds as classified in the Saffir-Simpson Scale. [Source: Wikipedia] Precipitation and wind On 15 July 2014, typhoon RAMMASUN moved across the northern Philippines reaching 1- minute sustained wind speeds of about 200 km/h. In the Philippines the typhoon was named GLENDA. At the weather station of Legazpi in the east of the Philippines, across which the typhoon passed, a 10-minute sustained wind speed of 45 kn (83 km/h) was recorded on 15 July 2014, 11 UTC. A total of 181 mm of rain fell at this location between 06 and 12 UTC. Continuing in northwestern directions across the South China Sea, RAMMASUN weakened slightly, but then it strengthened again over the warm waters. On 18 July, it was classified as a super-typhoon, reaching 1-minute sustained wind speeds of up to 250 km/h. RAMMASUN moved across the northeastern part of the island of Hainan and the southeastern Chinese mainland where the typhoon weakened to a tropical storm and then to a tropical depression in the course of the 19 July. Figure 3 shows the 24-hour precipitation totals for China from 18 July, 00 UTC, to 21 July, 00 UTC. The heavy rains in the south of the country are in clearly visible. They were trig- gered by RAMMASUN and relocated with the typhoon in western directions. On Hainan, re- gionally more than 250 mm of rain fell during 24 hours on the 18th, at Haikou in the north of the island even 400 mm. On 18 Juli 2014, 12 UTC, Haikou recorded a 10-minute sustained wind speed of 43 kn (80 km/h). Even when weakened to a tropical depression, precipitation totals of more than 100 mm in 24 hours were measured in the area covered by RAMMASUN on the Chinese mainland. 2 Fig. 3: 24-hour precipitation totals (in mm) for China. [Source: National Meteorologi- cal Center of CMA] Top: on 18 July 2014. Middle: on 19 July 2014. Bottom: on 20 July 2014. 3 Sources and further information . Deutscher Wetterdienst: Data archive. http://www.dwd.de . China Meteorological Administration (CMA): Products Service – Observations. http://www.cma.gov.cn/tqyb/v2/product/product_en.php . China Meteorological Administration (CMA): Super typhoon “Rammasun” has landed in Hainan. (18-07-2014) http://www.cma.gov.cn/en/NewsReleases/News/201407/t20140718_252812.html . China Meteorological Administration (CMA): Typhoon Rammasun has landed in coast of China for 3 times. (19-07-2014) http://www.cma.gov.cn/en/NewsReleases/News/201407/t20140719_252854.html . NASA: Rammasun (was 09W – Northwestern Pacific Ocean). http://www.nasa.gov/content/goddard/09w-northwestern-pacific-ocean/#.U8lwqBaUKA0 . NASA, Earth Observatory: Typhoon Rammasun Drenches Philippines. http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=84027 . NASA, Earth Observatory: Typhoon Rammasun Making Landfall in China. http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=84050 . National Meteorological Center of CMA: Observations – Observed precipitation. http://eng.weather.gov.cn/forecast.php?scroll=1&class_id=04080106 . Philippine Atmospheric, Geophysical & Astronomical Services Administration (PAGASA): http://www.pagasa.dost.gov.ph/ . Unisys: 2014 Hurricane / Tropical Data for Western Pacific. http://weather.unisys.com/hurricane/w_pacific/2014/index.php . Unisys: Tropical Advisory Archive. http://weather.unisys.com/hurricane/archive/ . Wikipedia: Typhoon Rammasun (2014). http://en.wikipedia.org/wiki/Typhoon_Rammasun_(2014) 4 .
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