关键词: 2018年秋季, 干旱状况及其演变, 影响, 成因

Abstract:

In autumn of 2018, the meteorological drought mainly occurred in Huabei, southeast of Northwest China，Huanghuai，Jianghuai, Jianghan, and parts of northern Jiangnan and Sichuan Province. The regional characteristics of drought in stages were obvious. Moderate to severe drought occurred in mid-early September, and the drought center was located in the western of Huanghuai. The drought eased from late September to early October, light drought occurred mainly and there was moderate drought in some places. The drought intensified in late October, and there was moderate to severe drought in Jianghan, Jianghuai and southern Huanghuai regions. The drought reduced significantly from the end of early November, light to medium drought occurred in parts of Huabei only. In addition,  there were two other regions experiencing staged drought in autumn of China. The light to moderate drought that existed in the south of Northeast China lasted from mid-late August to the end of September. The light to moderate drought occurred in late October in some border areas of Yunnan and Sichuan and developed in November, and in most of the southwest region moderate drought occurred by the end of November. Less precipitation and high temperature in summer and autumn were the main reasons of occurrence and development of autumn drought in these drought areas. The anomaly of 500 hPa height field caused by the change of sea temperature made regional drought occur in autumn in China.

Key words:  Autumn of 2018, drought conditions and their evolution, impact, cause