发表机构
Department of Earth and Atmospheric Sciences, Cornell University（康奈尔大学地球与大气科学系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究揭示降水强度分布随观测空间和时间分辨率变化，提出对数空间平移分布（平移模式）的框架来表征这种变化，强调比较网格化降水时需考虑尺度效应。
AI 中文摘要
降水强度随空间和时间分辨率的变化而变化，这对气候科学具有广泛的影响，然而这种依赖性的本质特征尚未得到充分刻画。我们研究了降水强度分布如何随空间和时间分辨率变化，并引入了一个框架来近似这些在不同分辨率之间的变化。利用重新网格化到不同网格尺寸的卫星-雨量计融合数据，我们构建了从IMERG的0.1°基础分辨率和FROGS数据库的1°基础分辨率到粗分辨率10°的空间分辨率范围内的降水量分布。类似地，我们使用雨量计观测数据，将其粗化到从1分钟到24小时的时间分辨率，以构建降水量分布。这种方法使我们能够排除物理差异，从而隔离分辨率对降水的影响。结果表明，即使物理过程没有变化，降水强度分布也会随空间和时间分辨率而变化。我们证明，这些依赖于分辨率的降水量分布变化可以通过在对数空间中平移分布而不改变其形状来有效表征，这种模式称为平移模式。我们的研究结果强调，在比较和解释来自模型或观测的网格化降水差异时，需要考虑尺度对降水的影响。
英文摘要
Precipitation intensity varies with both spatial and temporal resolution, with broad implications across climate science, yet the nature of this dependence is poorly characterized. We investigate how precipitation intensity distributions change with spatial and temporal resolutions and introduce a framework that approximates these changes between resolutions. Using merged satellite-gauge data regridded to various grid sizes, we construct precipitation amount distributions for spatial resolutions ranging from a base resolution of 0.1$^\circ$ for IMERG and 1$^\circ$ for the FROGS database to a coarse 10$^\circ$. Similarly, we use gauge observations coarsened to temporal resolutions ranging from 1-minute to 24-hours to construct precipitation amount distributions. This approach allows us to remove physical differences in order to isolate the effect of resolution on precipitation. Results show that the precipitation intensity distribution varies across spatial and temporal resolutions even without changes in physical processes. We demonstrate that these resolution-dependent changes in the precipitation amount distribution can be effectively characterized by shifting the distribution in logarithmic space without changing its shape, called the shift mode. Our findings emphasize the need to account for the effects of scale on precipitation when comparing and interpreting differences in gridded precipitation from models or observations.
Comments38 pages, 10 figures, plus supplementary material (3 pages, 2 figures). Submitted to Journal of Climate
