We present a data‐guided framework to explore the hydrological basis of the Budyko curve, focusing on the role of soil moisture in mediating the partitioning of precipitation into runoff and evaporation and the role of climate in this partitioning. The conceptual framework for the derivation of the Budyko curve builds on empirically based power law relationships for long‐term average scaled runoff (Q/P) and scaled evaporation (E/E_p), both as functions of long‐term average (equilibrium) soil moisture. A second component of the framework is an empirical power law relationship between equilibrium soil moisture and the aridity index, E_p/P. Combinations of these empirical power law relationships with the long‐term water balance equation give rise to a form of the Budyko curve, which is a close approximation to Budyko's original relationship and is mathematically similar to the Turc‐Pike equation, thus supporting the role of equilibrium soil moisture in giving rise to the Budyko curve. In the remainder of the paper, for special cases of the parameter values of the power law relationships, we independently derive both the soil moisture dependence on E_p/P as well as the Budyko curve itself that not only reproduces a new Budyko‐type curve, but can also explain the spread of the empirical data points away from the mean curve. The paper also raises fresh questions about how the empirical power law relationships that govern the soil‐mediated precipitation partitioning may have emerged and the role of vegetation in that mediation.

中文翻译：

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Budyko曲线的水文基础：土壤水分中介作用的数据导引探索

我们提出了一个数据指导框架，以探索Budyko曲线的水文基础，重点是土壤水分在介导降水向径流和蒸发的分区中的作用以及气候在分区中的作用。Budyko曲线推导的概念框架建立在基于经验的幂律关系上，作为长期平均（均衡）的函数，长期平均比例径流量（Q / P）和比例蒸发量（E / E _p）土壤湿度。该框架的第二个组成部分是平衡土壤水分与干旱指数E _p / P之间的经验幂律关系。。这些经验幂定律关系与长期水平衡方程的组合产生了Budyko曲线的形式，该曲线非常接近Budyko的原始关系，并且在数学上类似于Turc-Pike方程，因此支持了平衡土壤水分，从而产生Budyko曲线。在本文的其余部分，对于幂律关系的参数值的特殊情况，我们独立推导了土壤水分对E _p / P的依赖性Budyko曲线本身不仅可以重现新的Budyko型曲线，而且还可以解释经验数据点偏离均值曲线的范围。本文还提出了一些新的问题，即如何可能出现控制土壤介导的降水分配的经验幂律关系以及植被在该介导中的作用。