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机构地区:[1]宁夏气象防灾减灾重点实验室,银川市750002
出 处:《干旱区资源与环境》2008年第12期97-102,共6页Journal of Arid Land Resources and Environment
基 金:科技部社会公益研究专项"宁夏气候对全球气候变化的响应及其机制"(2004DIB3J121)资助
摘 要:根据宁夏20个气象观测站1961~2004年的日最低气温和地表0厘米地温资料,组合建立具有一定代表性的霜冻指标。研究表明:近44a宁夏霜冻发生次数呈明显下降趋势,春霜冻发生几率明显高于秋霜冻,大多数站终霜日的绝对变率大于初霜日;霜冻发生频次和各地拔海高度呈正相关关系,生长季、年均日最低温度与霜冻发生次数呈负相关关系;全区累积发生连续2d以上霜冻几率占发生总数的1/3以上,最多持续时间在5~6d;过程性霜冻主要表现为局地眭霜冻,虽然全区性霜冻发生几率不到1/5,但危害很大;春、秋霜冻随地域在农事关键期的发生几率差异较大。Based on the data of the day minimum temperature and the ground temperature of 20 meteorological observation stations of Ningxia from 1961 - 2004, the indication of frost was set. The results showed that the frequencies of frost in Ningxia declined obviously in the near 44a, the probability was of the spring frost higher than the autumn frost, the absolute variability of the last frost date in majority stations was larger than that of the first frost date. The frequency of frost correlated positively with the altitude, negatively with the growing season and the annual minimum temperature. The frost frequency that lasted over 2 days accounted for 1/3, most durations was 5 6d. The continuous frosts were mainly the local frost. Although the entire district frost had the probability less than 1/5, the harms was very serious. The spring frost and the autumn frost occurred differently with the region in the agronomic key period.
分 类 号:P468.021[天文地球—大气科学及气象学]
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