关键词: 中国, 低风速, 气候平均特征

Abstract:

 Based on the surface data of NCDC (National Climatic Data Center), the wind data of 345 stations during 1985 to 2014 are chosen, the characteristics of low wind-speed meteorology and the distribution of low wind-speed’s mean percentage in China are analyzed. Harbin, Urumqi, Beijing and Chengdu are chosen from 345 stations as representative cities, and the characteristics and annual variabilities of low wind-speed’s percentage are studied. The results show that: 1) The probability of occurrence of low wind-speed is about 40% in China during recent 30 years, as for the four representative cities, Harbin is the lowest (25%), Chengdu is the highest (60%); 2) Time-of-day occurrence: during the period of midnight and early morning, the probability of occurrence of low wind-speed is high; 3) Monthly occurrence: from September or October to next year January, the probability of low wind-speed maintains at a high level, the lowest probability happens in April; 4) Persistence, 36% low wind-speed condition can last at least 3 hours in China, in the four cities, 20% low wind-speed conditon can lasts at leat 12 hours in Chengdu; 5) Distribution, the probability of low wind-speed is high in the South and the inland, while it is low in the North and the coastal; 6) Annual variabilities, Harbin has increasing trend, while other three stations’s long-term trend is not obvious.

Key words: China, low wind speed(LWS), climatological characteristics