Intersectional weights between two different 12-digit Hydrologic Unit Code 12(HUC12) boundaries

This data release contains fractional intersectional weights used to crosswalk data from the National Water Use Program to the National Integrated Water Availability Assessment (IWAAs) projects. The Watershed Boundary Dataset (WBD; https://www.usgs.gov/national-hydrography/watershed-boundary-dataset) is a companion dataset to the National Hydrography Dataset and contains polygons that define the spatial boundaries of hydrologic units (i.e., the area of land the landscape that drains into a portion of the stream network). These are periodically updated as these boundary definitions are refined by incorporating better, more localized data. When aggregating data from multiple sources that rely on data from the WBD, a situation can occur where different datasets rely on different versions (or “snapshots”) of the WBD. This was the case for the IWAAs National Report which relied upon data using a version of the WBD found in the Mainstem Rivers data release (https://doi.org/10.5066/P92U7ZUT) as well as data that relied upon a version used by the National Water Use Program (https://doi.org/10.5066/P9FUL880). This dataset is the output of a pipeline of R code published as a software release (https://doi.org/10.5066/P1UANON8) and contains the fraction of spatial overlap (i.e., weights) between the subwatershed (HUC12) boundaries from these two versions of the WBD. These weights can be used as a crosswalk between the two snapshots of the WBD.

本数据集发布包含用于将美国国家用水计划（National Water Use Program）的数据转换至国家综合水可用性评估（National Integrated Water Availability Assessment, IWAAs）项目的分数相交权重。
流域边界数据集（Watershed Boundary Dataset, WBD；https://www.usgs.gov/national-hydrography/watershed-boundary-dataset）是国家水文数据集（National Hydrography Dataset）的配套数据集，包含用于定义水文单元（hydrologic units）空间边界的多边形——即汇入河网特定区段的陆地区域范围。该数据集会通过整合更优质、更具本地化特征的数据细化边界定义，并据此定期更新。
当对多个依赖流域边界数据集的源数据进行聚合时，可能出现不同数据集采用流域边界数据集不同版本（或“快照”）的情况。IWAAs国家报告即为此类情形：其既采用了主干河数据发布（https://doi.org/10.5066/P92U7ZUT）中的流域边界数据集版本，也采用了美国国家用水计划所使用的版本（https://doi.org/10.5066/P9FUL880）。
本数据集为以软件发布形式公开的R代码工作流的输出成果（https://doi.org/10.5066/P1UANON8），包含上述两个版本流域边界数据集的子流域（HUC12）边界之间的空间重叠占比（即权重）。此类权重可作为两个流域边界数据集快照之间的跨版本映射对照表。