• 论文 •

### 1960—2016年黄土高原多尺度干旱特征及影响因素

1. 陕西师范大学地理科学与旅游学院,西安 710119
• 收稿日期:2019-01-28 修回日期:2019-06-02 出版日期:2019-07-20 发布日期:2019-07-12
• 作者简介:

作者简介：孙艺杰（1991-）,女,辽宁兴城人,博士研究生,主要研究方向为资源环境与GIS。E-mail: jessicasun@snnu.edu.cn

• 基金资助:
国家自然科学基金项目(41801333,41701592);中国博士后科学基金(2019M650859,2019T120142)

### Spatiotemporal variations of multi-scale drought and its influencing factors across the Loess Plateau from 1960 to 2016

Yijie SUN(), Xianfeng LIU(), Zhiyuan REN, Shuangshuang LI

1. School of Geography and Tourism, Shaanxi Normal University, Xi’an 710119, China
• Received:2019-01-28 Revised:2019-06-02 Online:2019-07-20 Published:2019-07-12

Abstract:

Clarifying the spatiotemporal changes of drought and its influencing factors is of vital importance to the construction of ecological engineering and the sustainable development of social economy in the Loess Plateau. Using the daily precipitation data of 59 meteorological stations in the Loess Plateau, this paper attempts to describe the temporal and spatial variation trends of drought in the region on multi-time scales during 1960-2016. Based on Standardized Precipitation Evapotranspiration Index (SPEI), Sen+Mann-Kendall analysis, correlation analysis and other climate diagnosis methods, we analyzed the relationship between atmospheric circulation anomalies and drought variations. The results showed that: (1) The SPEI presented a downward trend in recent 57 years, showing a tendency from wet to dry. However, the change trend was not significant and the decline rate was only 0.032/10a. The significant drought trend occurred since the early 1970s and the late 1990s, the water-loggings were frequent during 1980s to the early 1990s. (2) The interannual SPEI (SPEI-12) indicated that there was a consistent drought trend in the whole Loess Plateau, the western part of Shanxi Province, the northern part of Ningxia Hui Autonomous Region, the central-eastern part of Gansu, Hohhot in Inner Mongolia Autonomous Region and Huashan in Shaanxi Province, which showed an significant drought trend, while a wetting tendency was observed in northwest and southwest parts of the Loess Plateau, and the north of Henan Province, moreover the increasing trend was obvious in Jingtai in Gansu Province and Xining in Qinghai Province, with the trend coefficient being respectively 0.36/10a and 0.35/10a. (3) On the inter-seasonal scales, drought trends were found in three seasons except winter, among them summer and autumn were remarkable, the decline rate was similar, at 0.03/10a. In spatial variation, there existed a regional difference of seasonal drought trend. The variation trend of spring drought was consistent with the interannual variation, in autumn the drought trend covered a larger range, which accounted for 64.53% of the total study area, while in winter the scope of drought decreased and was non-significant, and only 33.29% of meteorological stations showed a trend of drought. (4) IOD, NAO, PDO, AMO and ENSO3.4 were the dominant influencing factors for annual and seasonal precipitation variability over the Loess Plateau, the influence had obvious characteristics of interannual and interdecadal phase transition. Multiple regression model indicates that IOD and NAO could well explain drought variations over the Loess Plateau, which accounted for 22.98% and 12.23% of drought, respectively, compared to ENSO3.4. Our results suggest that precipitation over the Loess Plateau has a good correlation with Southwest Monsoon.