Variation Characteristic of Chilling Dew Wind for Double-Season Late Rice across southern China in 2020
Based on land use/cover change dataset at a resolution of 30m*30m, degree monitoring and index for chilling dew wind are extracted under underlying surface for double-season late rice, which are used to reveal characteristics for chilling dew wind. It is clear that the start date of for chilling dew wind in 2020 is earlier and the number of lasting days is longer than the average values during 2000-2020. Low to heavy chilling dew wind is occurred across rice area. There are 24.7% of rice exposed to chilling dew wind, which is the third largest since 2000. The percent of low, medium and heavy chilling dew wind is 9.7%, 12.8% and 4.9%, respectively. In terms of statistic in provinces, it is obvious that 99.9%, 99.4% and 91.8% rice is respectively affected by chilling dew wind in Hunan, Jiangxi and Zhejiang, which are higher than that in other provinces. The area percent subjected to chilling dew wind in Hunan, Hubei, Anhui and Jiangsu is largest since 2000, while that in Guangdong is small. The area percent subjected to heavy chilling dew wind in Jiangxi is largest, though the percent subjected to chilling dew wind is fifth largest. The major degree of chilling dew wind is low in Zhejiang, Fujian and Guangxi. The integrated index is 4.21, 7.16, 7.16 and 12.59 for double-season late rice, Hunan, Jiangxi and Hubei, which is second largest. Moreover, the index is the largest in Jiangxi and Zhejiang.