引入区域干旱评估的规范化表面调整降水指数 (NSPI)
Preeti Rajput1, Manish Kumar Sinha2, Nikhil Ghodichore3
1Department of Civil Engineering, Government Engineering College Raipur, Raipur 492015, Chhattisgarh, India; Department of Environmental & Water Resources Engineering, University Teaching Department, Chhattisgarh Swami Vivekanand Technical University Bhilai, Bhilai 491107, Chhattisgarh, India.
The Science of the total environment
|September 3, 2025
概括
通过将气候数据与陆地表面特征相结合, 一个新的干旱指数 - - 规范化表面调整降水指数 (NSPI) 更好地捕捉干旱的演变. 这种先进的指数为早期预警系统提供了更好的干旱模式检测.
科学领域:
- 水文学
- 气候科学
- 环境监测
背景情况:
- 干旱的频率和严重程度越来越受到人类活动和气候变化的影响.
- 传统的干旱指数,如标准化降雨指数 (SPI),往往无法捕捉大气和陆地表面过程之间的复杂相互作用.
- 人类引起的水文循环变化正在重塑人类时期的干旱发展和持续性.
研究的目的:
- 引入正常化表面调整降水指数 (NSPI),以更好地代表干旱演变.
- 整合气候数据与水域规模的表面特征,以改善干旱评估.
- 解决传统指数在捕捉大气和陆地表面对干旱的影响方面的局限性.
主要方法:
- 通过将气候数据与表面特征合并,开发了标准化表面调整降水指数 (NSPI).
- 利用遥感,再分析数据集,陆地表面模型和地面观测的数据.
- 结合了"损失术语"和使用主要组件分析推导的复合变量,以计算水分可用性,能量输入和水分传输效率.
主要成果:
- 与传统指数相比,NSPI在多个时间尺度上表现优异.
- 该指数通过与卫星衍生的植被数据 (NDVI) 对齐,准确地反映干旱模式.
- 在Mahanadi河流域的应用揭示了比SPI更详细的空间干旱模式.
结论:
- 通过整合土地表面特性, NSPI提供了更全面的干旱动态表现.
- 提高国家干旱预警指数的准确性为开发有效的干旱预警系统提供了更强大的基础.
- 气候变化对干旱状况的影响,如气温和风速的上升.
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