资源环境科技发展态势分析平台

Constructing an accurate, continental, in-situ-based, kilometer-scale, long-term record of the precipitation field and its spatiotemporal changes remains a significant challenge. Here we determine the extreme-value behavior of the NEXRAD Stage IV radar-based quantitative precipitation estimate (QPE). We find that the climatology of 5-year daily return values in CONUS East of the Rocky Mountains shows only slight variability on spatial scales smaller than 100 km. In light of this finding, we test whether rain-gauge-only daily precipitation datasets can produce accurate extreme-value behavior at spatial scales finer than the spacing between gauges. We find that the 5-year daily return values are accurate at locations far from rain gauges only if the interpolation between gauges is carried out appropriately for extremes. Precipitation statistics derived from in-situ rain gauge data are therefore of sufficient spatial resolution to faithfully capture daily extremes over much of the eastern United States.