基于地理加权回归和卫星地球观测的综合干燥指数
Younes Khosravi1, Saeid Homayouni2, Andre St-Hilaire3
1Environmental Science Research Laboratory, Department of Environmental Science, Faculty of Science, University of Zanjan, 45371-38791 Zanjan, Iran; Centre Eau Terre Environnement, Institut National de la Recherche Scientifique (INRS), Quebe, QC G1K 9A9 Quebec, Canada.
The Science of the total environment
|November 24, 2023
概括
一个综合地理加权干旱指数 (IGWDI) 已开发,以模拟干旱条件. IGWDI-CP模型被证明是最有效的,揭示了伊朗各地广泛的干旱严重程度,特别是在西南部.
科学领域:
- 环境科学 环境科学
- 气候学 气候学 气候学
- 遥感 遥感 遥感 遥感
背景情况:
- 干旱是一种具有复杂影响的破坏性自然灾害.
- 单变量干旱指数不足以进行全面评估.
- 需要综合的方法来捕捉多面干旱条件.
研究的目的:
- 为干旱建模开发和验证一个综合地理加权干旱指数 (IGWDI).
- 通过IGWDI评估伊朗高原的干旱状况.
- 确定干旱监测最有效的模型.
主要方法:
- 开发了综合地理加权干燥指数 (IGWDI).
- 综合气候参数 (降水,温度,蒸发) 和基于遥感的干旱指数 (PCI,VCI,TCI,SMCI).
- 使用地理加权回归 (GWR) 模型预测TVDI (训练变量干旱指数) 在两个不同的模型中:IGWDI-CP和IGWDI-RSDI.
主要成果:
- 确定IGWDI-CP模型是所有月份干旱监测最适合的模型.
- 在20多年 (2003-2022年) 中,约90%的伊朗高原经历了不同程度的干旱.
- 严重和极端的干旱状况在7月份最为明显,影响了71%的地区,特别是在中部,南部和西南部地区.
结论:
- IGWDI-CP模型有效地描述了伊朗高原的干旱状况.
- 广泛的干旱严重程度需要有针对性的管理策略,特别是在伊朗西南部.
- 这些发现支持环境可持续性,农业规划和气候变化适应努力.
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