• CN 62-1175/P
• ISSN 1006-7639
• 双月刊
• 中国科技核心期刊
• 中国学术期刊综合评价数据库统计源期刊
• 中文科技期刊数据库收录期刊

• 论文 •

### 基于SPEI的黄淮地区夏季干旱时空异常特征及成因

1. 1.江苏省徐州市气象局，江苏徐州221000；2.南京信息工程大学气象灾害预报预警与评估协同创新中心，
气象灾害教育部重点实验室，气候与环境变化国际合作联合实验室，江苏 南京210044；
3.中国气象局，北京100081；4.国家气象中心，北京100081）
• 出版日期:2018-09-04 发布日期:2018-09-04

### Spatial and Temporal Characteristics of Summer Drought Anomaly and Its Causes Based on SPEI in Huang-Huai Area

AN Di1, LI Dongliang2, WANG Ziqiang3,WU Yan1, LV Xiang1, YANG Xuan4

1. (1. Xuzhou Meteorological Bureau of Jiangsu Province, Xuzhou 221000, Jiangsu, China;
2. College of Atmospheric Science, Nanjing University of Information Science & Technology,
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,
Key Laboratory of Meteorological Disaster, Ministry of Education, Nanjing 210044, China;
3. China Meteorological Administration, Beijing 100081, China;
4. National Meteorological Centre of China Meteorological Administration, Beijing 100081, China)
• Online:2018-09-04 Published:2018-09-04

Abstract:

Based on the monthly temperature and precipitation observation data from 147 meteorological stations during 1962-2015 in the Huang-Huai River Basin and surrounding area. The standardized precipitation evapotranspiration index (SPEI) was used to analyze the summer drought change and its abnormal cause. The results show that the Huang-Huai area has maintained a stable and slightly drought trend in summer in recent 54 a. In the 1990s, the area experienced the evolution of the first wet and then dry. The first three EOF （empirical orthogonal function） modes of SPEI in summer in the Huang-Huai area showed consistent variation, the north-south anti-phase variation and northeast-southwest anti-phase variation, respectively. Discussion on the causes of drought in summer indicated that compared with flood years, it occurred either type I or type III rain in drought years. From June to August, the causes of drought in the Huang-Huai area were intra-seasonal differences. Using composite analysis method to discuss the characteristics of atmospheric circulation under the spatial distribution pattern of drought anomaly in the Huang-Huai area, when the intensity of the polar vortex in Asia was relatively weak in June, the precipitation in the Huang-Huai area was less and the drought was more frequent. The position variation of the western Pacific subtropical high (WPSH) in July had an important impact on drought and flood in the Huang-Huai area. The westward ridge point of the WPSH extended eastward, which was located east of 129°E, the possibility of drought in the Huang-Huai area was greater in July. When the intensity of WPSH was weak in August, the risk of drought in the Huang-Huai area increased. When the intensity of the surface heat field on the Tibetan Plateau was stronger in summer, cold air from the mid-latitude was weak, and it was difficult to affect the Huang-Huai area. At the same time, the position of WPSH was abnormally northward and westward, which resulted in drought in the area.

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