Data from: The 1991 California "Miracle March”: Precipitation Myth or Miracle?

This object contains the data and code necessary to reproduce the plots and analysis for "The 1991 California “Miracle March”: Precipitation Myth or Miracle?", published in Environmental Research Communications by Poulsen et al. (2025). The gridded precipitation data sets used in this study and included in this collection are from the PRISM Climate Group at Oregon State University. The Livneh daily precipitation data set used for Figure 3 is from NOAA PSL. The geopotential height and wind data are from NCEP/NCAR. The vertically integrated vapor transport (IVT) data set was computed by the Center for Western Weather and Water Extremes (CW3E) using NASA data (MERRA-2). All data is publicly available from the institutions listed, and citations for data sets are located in the "Data availability statement" at the end of the manuscript.

In California, water year 1991 was characterized by heavy precipitation in March, following one of the driest winters on record, lessening the burden of drought entering the dry season. The methods used to analyze the data in this collection can be viewed in the code included (Python and R) and act as a model to work with this data to analyze the climate context and impacts of extreme precipitation events on seasonal totals. All of the data sets in this collection are in the NetCDF file format. The data files and scripts are organized into collection components based on data type and named respectively as Python code, Precipitation data, Geopotential height and wind data, Vertically-integrated water vapor transport (IVT) data, and Figure 3 data. The Readme file provides greater details on the files located in each collection component.

本数据集包含复现Poulsen等人（2025）发表于《环境研究通讯（Environmental Research Communications）》的论文《1991年加利福尼亚“奇迹三月”：降水神话还是奇迹？》所需的全部绘图与分析数据及代码。本研究使用并收录于本数据集的网格化降水数据集，源自俄勒冈州立大学PRISM气候组（PRISM Climate Group）；用于制作图3的Livneh逐日降水数据集取自NOAA PSL；位势高度与风场数据源自NCEP/NCAR；垂直积分水汽输送（Vertically Integrated Vapor Transport, IVT）数据集由西部天气与水极端事件中心（Center for Western Weather and Water Extremes, CW3E）基于NASA的MERRA-2数据计算生成。所有数据均可从上述机构公开获取，数据集的引用信息详见论文末尾的“数据可用性声明”。

1991年加利福尼亚水年以3月出现强降水为显著特征——此前该冬季为有记录以来最干燥的冬季之一，此次强降水有效缓解了旱季来临前的干旱压力。本数据集中的数据分析方法可通过附带的Python与R代码查阅，该方法可作为处理此类数据、分析极端降水事件对季节降水总量的气候背景与影响的参考范式。本数据集收录的所有数据集均采用NetCDF文件格式存储。数据文件与脚本按数据类型划分为多个组件，分别命名为Python代码、降水数据、位势高度与风场数据、垂直积分水汽输送（IVT）数据以及图3数据。自述文件（Readme）将详细说明各组件内的文件详情。