海口市低温阴雨气候特征及对农业的影响

Climatic Characteristics of Low Temperature and Rainy Weather in Haikou City and Its Effects on Agricultural Production

基于海口市永庄地面观测站1956—2013年气候整编资料和20个乡镇2008—2013年观测的历史气象资料分析表明:近58年来海口市低温阴雨过程以轻度为主,重度过程具有持续时间偏长的特点。当年12月至次年1月低温阴雨过程以干冷为主,而2月低温阴雨过程以湿冷为主,且持续时间最长,影响程度最重。总体来说,海口市低温阴雨过程年频数和持续日数呈下降趋势,但变异性增大,过程持续日数在4 d和5 d比例最大。从分布空间来看,低温阴雨过程年均日数和次数自西南向东北逐渐递减,且厄尔尼诺发生年的冬季,低温阴雨过程偏轻,拉尼娜发生时,低温阴雨过程偏重。综上所述,海口市12月至次年2月低温阴雨过程强度总体减弱,这对减轻低温阴雨灾害对农业生产的影响有利,但过程变异性增大,这也增大了异常低温阴雨天气对农业生产造成重大灾害的风险,最终加剧了农业生产的不稳定性和不可持续性。故应重视极端气象事件对农业生产的监测与预警,并及时有效采取相应防灾减灾措施,以增强海口市农业生产的避灾防灾能力。

Based on the meteorological records from 1956 to 2013 in Yongzhuang Ground Weather Observation Stations and historical weather data from 2008 to 2013 of 20 townships in Haikou City ,the analysis results showed that： Over the past 58 years ,low temperature and rainy weather showed the dry-cold from December to January of next year,however,wet-cold usually occur in February,and have the longer duration and heavier influence.Overall ,annual frequency and continuous days of low temperature and rainy weather showed a downward trend ,but the variability increased, the proportion of continuous days in 4 days and 5 days was maximum.From the point of distn＇bution in space,the annual average days and times of low temperature and rainy weather gradually decreased from southwest to northeast,when the E1 Nino occurred,low temperature and rainy weather is light, and La Nina occurred,the process became severe.In summary,the process of low temperature and rainy weather overall weakened,and this had a favorable impact on agricultural preduction.However,the variability of process been increased,which increased the risk of abnormal meteorological disaster to agricultural production ,and ultimately exacerbate the instability of agricultural production.We should strengthen the capacity of monitoring and warning on agricultural production if extreme weather events occurred ,and take appropriate measures to enhance capacity of disaster prevention and reduction on agricultural production in Haikou City.