云浮高温天气及其环流形势统计与分析

Statistical Summary and Analysis of the High-Temperature Weather in Yunfu City and Its Associated Circulation Patterns

为加深对云浮高温天气特征的认识,对云浮地区1981-2010年高温天气及其与副高、热带气旋之间关系进行统计分析.结果表明：云浮地区年高温天气大体呈增加趋势,测站局地环境不一致导致各测站高温天气年变化的并不一致.云浮地区高温天气主要出现在6-8月,7月最多,8月次之.云浮地区高温环流形势可分为4类：副高型、台风Ⅰ型、台风Ⅱ型和其它型.500 hPa位势高度（台风强度）与云浮地区台风Ⅰ型（台风Ⅱ型）高温的关系不明显.500hPa位势高度较高有利于台风Ⅱ型、副高型、其它型高温的发生发展.500hPa位势高度大值中心位于测站以北（以西）有利于台风Ⅱ型（其它型）高温发生发展,位于测站以东时副高型高温较多,位于测站东南则不利于高温天气发生发展.台风中心位于测站东北、东、东南三个方位,台风中心与测站距离600～1 600 km,台风强度在TS及以上时,有利于台风Ⅰ型高温的发生发展.台风中心位于测站东方方位,台风中心与测站距离1600～2 200 km,有利于台风Ⅱ型高温的发生发展.

To have deeper understanding of the characteristics of the high-temperature weather in Yunfu, this work runs a statistical analysis of the relationships between the high-temperature weather in Yunfu in 1981 to 2010 and the subtropical high and tropical cyclones. As shown in our study, the high-temperature weather shows a generally increasing annual trend and inconsistent local environment of observation sites result in inconsistent annual variation across the area. It mainly happens in June to August and July is the month with the most occurrences, followed by August. Circulation patterns are of the subtropical high, tropi- cal cyclones and other systems. A relatively high 500 hPa geopotential height is conducive to the generation and development of the high-temperature weather. The position of the large-value center of this height rela- tive to the observation site can be indicative of whether high temperature can occur; when it is to the east of an observation station, high temperature is likely to happen and when it is to the southeast it is unlikely to happen. When the eye of a tropical cyclone is located to the northeast, east and southeast of the site by distances between 600 and 1 600 km and with the intensity of tropical storm or above, high temperature is likely to happen. When the eye is to the east of the site by distances between 1 600 and 2 200 km, high temperature is also likely to happen.