On the compounding of nitrate loads and discharge
On the compounding of nitrate loads and discharge
复制标题
论硝酸盐负荷与排放的复合
DOI：
10.1002/jeq2.20458
复制
发表时间：
2023
影响因子：
2.4
通讯作者：
Wahl, Thomas
中科院分区：
文献类型：
--
作者：
Kim, Taereem;Villarini, Gabriele;Kim, Hanbeen;Jane, Robert;Wahl, Thomas
复合极端可能来自多个驱动因素的组合，甚至非极端单变量事件也可能联合收割机造成巨大的社会和经济影响。在这项研究中，我们模拟多变量复合事件，重点是潜在的相互作用的硝酸盐负荷和放电。我们在爱荷华州的七个美国地质调查站使用每日排放量和硝酸盐负荷。我们应用双侧条件抽样方法，该方法分别推导出以排放和硝酸盐负荷为条件的两个联合概率。我们的研究结果表明，排放量和硝酸盐负荷之间存在依赖关系，这可以通过双变量建模和随后的联合年度排放概率（AEPs）估计来描述。极端排放和极端硝酸盐负荷的联合AEP的大小在不同地点表现出不同的结构，突出了这两个量在控制其复合方面的不同作用。在检查给定AEP的设计值的范围时，我们发现最大的变异性通常与高农业强度、高生猪密度和肥料支出有关。
Compound extremes can arise from combinations of multiple drivers, and even non‐extreme univariate events can combine to cause large societal and economic impacts. In this study, we model multivariate compound events focusing on the potential interaction of nitrate loads and discharge. We use daily discharge and nitrate loads at seven US Geological Survey sites in the state of Iowa. We apply a two‐sided conditional sampling method, which derives two joint probabilities conditioning on discharge and nitrate loads, respectively. Our results show that there is a dependence between discharge and nitrate loads, which can be described through bivariate modeling and the subsequent estimation of their joint annual exceedance probabilities (AEPs). The magnitude of the joint AEPs to extreme discharge and extreme nitrate loads exhibit different structures across the different sites, highlighting the different roles of these two quantities in controlling their compounding. In examining the ranges in design values for a given AEP, we found that the largest variability in highly likely values was generally associated with high agricultural intensity, high hog density, and fertilizer expenditures.