Peak Streamflow Data, Climate Data, and Results from Investigating Hydroclimatic Trends and Climate Change Effects on Peak Streamflow in the Central United States, 1921–2020

Peak-flow frequency analysis is crucial in various water-resources management applications, including floodplain management and critical structure design. Federal guidelines for peak-flow frequency analyses, provided in Bulletin 17C, assume that the statistical properties of the hydrologic processes driving variability in peak flows do not change over time and so the frequency distribution of annual peak flows is stationary. Better understanding of long-term climatic persistence and further consideration of potential climate and land-use changes have caused the assumption of stationarity to be reexamined. This data release contains input data and results of a study investigating hydroclimatic trends in peak streamflow (peak flow) in the Central United States, including nine states (Illinois, Iowa, Michigan, Minnesota, Missouri, Montana, North Dakota, South Dakota, and Wisconsin). Peak flow records from unregulated U.S. Geological Survey (USGS) streamgages were used to evaluate changes over 30-, 50-, 75-, and 100-year trend periods, all ending in water year 2020. This data release contains station lists of the streamgages used in each of the nine states, the peak streamflow input data and peak streamflow analysis results, and the climate input data and climate analysis results. See "Station_Lists.zip" on the landing page for station lists (in text file format) for each state included in the study.

洪峰流量频率分析在诸多水资源管理应用中至关重要，涵盖河漫滩管理与重要水工构筑物设计等场景。美国《Bulletin 17C》中提出的洪峰流量频率分析联邦指南，假设驱动洪峰流量变异性的水文过程统计特性不随时间改变，因此年度洪峰流量的频率分布为平稳分布。随着对长期气候持续性的认知不断深化，以及对潜在气候变化与土地利用变化的进一步考量，平稳性假设已受到重新审视。本数据集发布内容包含一项针对美国中部地区（涵盖伊利诺伊州、艾奥瓦州、密歇根州、明尼苏达州、密苏里州、蒙大拿州、北达科他州、南达科他州及威斯康星州共9个州）溪洪峰流量（peak streamflow，简称洪峰流量）的水文气候趋势研究的输入数据与分析结果。本研究采用未受调控的美国地质调查局（U.S. Geological Survey, USGS）水文测站的洪峰流量记录，针对均截至2020水文年的30年、50年、75年及100年趋势周期开展变化评估。本次数据集发布内容包含本次研究涉及的9个州各自所用水文测站的站点列表、溪洪峰流量输入数据与分析结果，以及气候输入数据与气候分析结果。可前往数据集首页的"Station_Lists.zip"下载本研究涉及各州的站点列表（文本文件格式）。