中国农业气象 ›› 2021, Vol. 42 ›› Issue (11): 962-974.doi: 10.3969/j.issn.1000-6362.2021.11.007

• 农业气象灾害 栏目 • 上一篇    下一篇

基于SPEI_PM指数的渭河流域气象干旱时空演变特征

杨睿,耿广坡,周洪奎,王涛   

  1. 1. 西安科技大学测绘科学与技术学院,西安 710054;2. 浙江省农业科学院数字农业研究所,杭州 310021
  • 收稿日期:2021-03-01 出版日期:2021-11-20 发布日期:2021-11-15
  • 通讯作者: 耿广坡,讲师,主要从事干旱监测和风险评估研究,E-mail: gengguangpo@xust.edu.cn E-mail:gengguangpo@xust.edu.cn
  • 作者简介:杨睿,E-mail: 15074292109@163.com
  • 基金资助:
    国家自然科学基金项目(41807503);陕西省教育厅科研计划项目(21JK0771);西安科技大学博士启动金项目(2017QDJ030)

Spatial-temporal Evolution of Meteorological Drought in the Wei River Basin Based on SPEI_PM

YANG Rui, GENG Guang-po, ZHOU Hong-kui, WANG Tao   

  1. 1. College of Geomatics, Xi'an University of Science and Technology, Xi’an 710054, China; 2. Institute of Digital Agriculture, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021
  • Received:2021-03-01 Online:2021-11-20 Published:2021-11-15

摘要: 利用渭河流域25个气象站点1980−2018年月值气象数据集,基于Penman-Monteith蒸散模型计算多个时间尺度的标准化降水蒸散发指数(SPEI),分析渭河流域气象干旱的演变、趋势、影响范围、发生频率和持续时间等时空变化特征,以期为渭河流域防灾减灾管理提供科学依据。结果表明:(1)近39a来渭河流域有明显的干湿周期变化,但整体上呈变干的趋势,干旱时段主要集中在1995−2009年,其中以2000−2009年的干旱站次比最大,平均达到36%,且干旱持续时间最长,约3.6个月,1980−1989年干旱持续时间最短,约1.6个月;(2)渭河流域秋季总体呈湿润变化趋势,而春季和夏季干旱在不断加剧,是区域年际干旱的主要驱动力;(3)渭河流域干旱以危害性较小的轻中旱为主,但2000年前后出现严重及极端干旱的站次相对较多,其中1997年研究区内发生的干旱程度较高,影响范围较广;(4)不同时间尺度各等级干旱发生频率的变化规律表现一致,均呈现出干旱等级越高发生频率越低的态势,且极端干旱在年际尺度内发生次数较为频繁,从空间上看渭河流域东北部是干旱多发区。总之,近39a来渭河流域总体干旱较为严重的时段为2000−2009年,且研究区内干旱呈北重南轻特征,因此北部地区仍需加强防灾管理。

关键词: SPEI_PM, 多时间尺度, 气象干旱, 时空特征, 渭河流域

Abstract: The frequent and long-lasting droughts have caused many adverse effects on the social economy and ecological environment. Understanding the drought characteristics in the Wei river basin is of great significance to the adjustment of regional economic structure and the rational utilization of water resources. Based on the monthly meteorological data set of 25 stations in the Wei river basin from 1980 to 2018 and the Penman-Monteith equation, the standardized precipitation evapotranspiration index (SPEI) of multiple time scales were calculated, and the spatial-temporal characteristics of drought were analyzed, including its evolution, trend, affected area, frequency and duration. The results showed that: (1) there was an obvious periodic variation of dry-wet status in the Wei river basin during the past 39 years, but the drying trend was appeared as a whole. The drought period was mainly concentrated in 1995−2009, among which the drought occurring stations ratio in 2000−2009 was the largest, with an average value of 36%. The longest drought duration was occurred in 2000−2009, about 3.6 months, and the shortest drought duration was occurred in1980−1989, about 1.6 months. (2) There was a trend of wetness in autumn, while the droughts in spring and summer was increasingly intensified, which was the main driving force of the inter-annual drought in the Wei river basin. (3) The droughts in the Wei river basin were dominated by mild and moderate droughts, but there were relatively more stations with severe and extreme droughts around 2000, among which the droughts occurred in 1997 had a higher degree and a wider range of impacts. (4) The variation of drought frequency for different drought levels at different time scales was consistent, showing that the higher the drought level, the lower the frequency. In addition, extreme droughts occurred more frequently at the annual scale, and the northeastern region of the Wei river basin was a drought-prone area in space. Above all, the drought condition in the Wei river basin was more severe from 2000 to 2009, and the droughts in the northern region was severer than that in the southern region, so more attentions should be paid to strengthening disaster prevention management in the northern area.

Key words: SPEI_PM, Multiple time scales, Meteorological drought, Spatial-temporal characteristics, Wei river basin