Daily County-Level PM2.5 Concentrations, 2001-2019

This dataset provides modeled predictions of PM2.5 levels from the EPA's Downscaler model. Data are at the county level for 2001-2019. These data are used by the CDC's National Environmental Public Health Tracking Network to generate air quality measures. Census tract-level datasets contain estimates of the mean predicted concentration and associated standard error. Please refer to the metadata attachment for more information. Learn more about outdoor air quality on the Tracking Network's website: https://ephtracking.cdc.gov/showAirLanding.action. By using these data, you signify your agreement to comply with the following requirements: 1. Use the data for statistical reporting and analysis only. 2. Do not attempt to learn the identity of any person included in the data and do not combine these data with other data for the purpose of matching records to identify individuals. 3. Do not disclose of or make use of the identity of any person or establishment discovered inadvertently and report the discovery to: [e-mail]. 4. Do not imply or state, either in written or oral form, that interpretations based on the data are those of the original data sources and CDC unless the data user and data source are formally collaborating. 5. Acknowledge, in all reports or presentations based on these data, the original source of the data and CDC. 6. Suggested citation: Centers for Disease Control and Prevention. National Environmental Public Health Tracking Network. Web. Accessed: insert date. www.cdc.gov/ephtracking.

本数据集提供基于美国环境保护署（EPA）降尺度模型（Downscaler model）的PM2.5浓度模拟预测结果。数据覆盖2001-2019年的县级行政区域尺度。这些数据被美国疾病控制与预防中心（CDC）的国家环境公共卫生追踪网络用于生成空气质量指标。普查小区尺度数据集包含预测浓度均值的估计值及其相关标准误差。更多信息请参考元数据附件。如需了解更多室外空气质量相关内容，请访问追踪网络官网：https://ephtracking.cdc.gov/showAirLanding.action。使用本数据即表示您同意遵守以下要求：1. 仅将数据用于统计报告与分析。2. 不得试图识别数据中包含的任何个人身份，亦不得将本数据与其他数据结合以匹配记录并识别个体。3. 如无意中发现任何个人或机构身份信息，不得披露或使用该信息，并需向以下邮箱报告：[e-mail]。4. 除非数据使用者与数据源方存在正式合作，否则不得以书面或口头形式暗示或声明基于本数据的解读代表原始数据源方及CDC的观点。5. 在所有基于本数据的报告或展示中，需注明数据原始来源及CDC。6. 建议引用格式：美国疾病控制与预防中心. 国家环境公共卫生追踪网络. 网络. 访问日期：[插入日期]. www.cdc.gov/ephtracking。