一个详细的研究量化和模拟干旱特征,使用不同的copula家庭
Ishfaq Ahmad1, Touqeer Ahmad2, Shafique Ur Rehman3
1Department of Mathematics and Statistics, Faculty of Basic and Applied Sciences, International Islamic University, 44000 Islamabad, Pakistan.
Heliyon
|February 15, 2024
概括
这项研究使用先进的形模型分析了巴鲁吉斯坦的干旱模式. 调查结果显示,严重的干旱可能会发生,返回时间更长,有助于水资源管理.
科学领域:
- 水文和水资源水文与水资源
- 环境科学 环境科学
- 统计建模 统计建模
背景情况:
- 干旱分析对于水资源管理至关重要,特别是在巴鲁吉斯坦等干旱和半干旱地区.
- 传统方法通常独立分析干旱的严重程度和持续时间,可能缺少关键的联合行为.
- 了解干旱模式需要强大的统计工具,能够捕捉复杂的依赖关系.
研究的目的:
- 为了分析巴鲁吉斯坦的干旱模式,使用基于copula的两变概率模型.
- 开发干旱特征的严重度持续时间频率 (SDF) 曲线.
- 评估不同合物适用于模拟干旱严重程度和持续时间的合适性.
主要方法:
- 标准化降水指数 (SPI) 的计算,使用六个月期间从十个地点的月度降水数据.
- 使用Log-Normal分布建模干旱的严重程度和持续时间.
- 应用和比较各种双变性,包括Gumbel,以模拟和验证干旱特征与观察到的数据.
主要成果:
- 对于模拟干旱的严重程度和持续时间,Log-Normal分布被认为是合适的.
- 在模拟关节干旱严重程度和持续时间特征方面,Gumbel copula与其他copula相比表现出更好的表现.
- 用得出的条件分布和回归期来构建SDF图表,表明在特定持续时间的更高回归期出现严重干旱的可能性.
结论:
- 基于的联合建模技术对于生成干旱严重程度和持续时间的频率曲线是有效的.
- 在干旱研究中,Gumbel copula是一种强大的选择,用于极端价值分析.
- 这项研究为加强脆弱地区的水资源管理和干旱减缓战略提供了有价值的见解.
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