江苏沿江和江淮区褐飞虱前期迁入量与太平洋海温场的遥相关及其可能机制

Teleconnection between Pacific sea surface temperature and the early immigration of brown planthopper (Nilaparvata lugens Stl) in the Yangtze and Yangtze-Huai River Valley of Jiangsu Province and its possible mechanism

为筛选出有效的长期预测因子,对江苏通州和江苏淮安褐飞虱前期迁入量与太平洋海温场遥相关时空分布分别进行了相关分析及其稳定性检验。结果表明:与褐飞虱前期迁入量连续稳定显著相关的海温区,在空间上主要分布在中太平洋和南太平洋(72.4%),在时间上主要分布在前两年和前一年(82.7%)。分别分析褐飞虱前期迁入量与当年4-8月上旬各旬降水量、平均温度、当年1-8月500hPa西太平洋副高月平均指数之间的两两相关关系,并比较这三者与前期太平洋海温场遥相关时空分布的异同。根据对两地的个例分析表明:前一冬春季赤道中东太平洋海温的变化引起当年6月副高面积指数的变化,影响江苏通州当年6月下旬降水,从而影响江苏通州褐飞虱的前期迁入量;前两年春夏季赤道中东太平洋海温的变化引起当年5月副高北界位置的变化,影响江苏淮安当年7月上旬降水,从而影响江苏淮安褐飞虱的前期迁入量。在此基础上,对褐飞虱前期迁入量与太平洋海温场遥相关的可能机制提出“海温→大气环流(副高)→气候→褐飞虱前期迁入”的一般假想模式。

To select effective long-term forecasting factors, teleconnection between the early immigration of brown planthopper （BPH） in Tongzhou and Huai＇ an, Jiangsu and Pacific sea surface temperature （SST） anomalies from January 2 years ago to the current June was analyzed, and their correlation stabilities were tested. The results indicated that there were different spatio-temporal distributions of significant correlative SST regions in the two stations. These SST regions were mainly distributed in the Central and South Pacific （72.4%） and in one and two years earlier （82.7%）. The relationship between every two of the following three factors was investigated： the eady immigration of BPH, the average temperature or precipitation of every ten days from April to August and the monthly mean indices of 500 hPa Western Pacific Subtropical High. Then, teleconnection between Pacific SST anomalies and each of the above three factors, which were significantly correlated with each other, were compared. The case analysis indicated that SST over the midEastern Equatorial Pacific of the previous winter and spring affected the area index of Western Pacific Subtropical High in this June, which influenced the precipitation of the last ten days of June in Tongzhou, accordingly influencing the early immigration of BPH in Tongzhou; while the SST over the mid-Eastern Equatorial Pacific of spring and summer two years ago affected the North boundary of Western Pacific Subtropical High in the current May, which influenced the precipitation of the first ten days of July in Huai＇an, accordingly influencing the early immigration of BPH in Huai＇an. Finally, the possible mechanism of the teleconnection between the early immigration of brown planthopper and Pacific sea surface temperature was proposed as ＂sea surface temperature → atmospheric circulation → climate → the early immigration of brown planthopper＂.