基于非线性复合干旱指数的河南干旱的空间和时间演变分析
Chaojie Jin1, Ning Jiang2, Xiaoran Tian1
1College of Water Resources and Electricity, Heilongjiang University, Harbin, 150006, China.
Scientific reports
|November 26, 2024
概括
一个新的综合干旱指数 (CCDI) 有效地评估了河南省的气象和农业干旱. 分析显示,干旱趋势和干旱中心的变化越来越大,未来的预测表明,在某些季节持续存在干旱条件.
科学领域:
- 水文学的水文学
- 农业科学 农业科学
- 气候学 气候学 气候学
背景情况:
- 河南省的干旱减缓和水资源规划需要对气象和农业干旱进行准确的评估.
- 了解干旱的空间和时间演变对于有效的区域规划至关重要.
研究的目的:
- 为河南省构建和验证多变量复合干旱指数 (CCDI).
- 分析1982年至2022年干旱演变的空间和时间特征.
- 预测该地区未来的干旱趋势.
主要方法:
- 开发一个综合干旱指数 (CCDI),使用D Vine copula,结合降水量,潜在的蒸发透气,土壤水分和NDVI.
- 与标准化降水蒸发透气指数 (SPEI) 和标准化土壤湿度指数 (SSI) 的相关性分析.
- 用线性趋势,M-K测试,干旱重心和赫斯特指数对空间时间干旱演变的分析,用于未来的预测.
主要成果:
- CCDI有效地整合了气象和农业干旱评估,显示与SPEI和SSI有很强的相关性.
- 干旱频率在时间尺度上有所变化,所有季节都呈现着增加的趋势.
- 干旱强度主要为轻度至中度,重心以南北方向转移.
- 未来的预测表明春季和冬季持续的干旱趋势,夏季和秋季区域差异较大.
结论:
- 开发的CCDI为评估河南省综合干旱状况提供了可靠的工具.
- 观察到的干旱趋势和空间变化需要适应性水资源管理策略.
- 未来气候预测强调需要积极的干旱减缓和准备计划.
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