Formaldehyde (HCHO), a known carcinogen classified as a hazardous pollutant by the United States Environmental Protection Agency (U.S. EPA), is measured through monitoring networks across the U.S. Since these data are limited in spatial and temporal extent, model simulations from the U.S. EPA Community Multiscale Air Quality (CMAQ) model are used to estimate ambient HCHO exposure for the EPA National Air Toxics Assessment (NATA). Here, we employ satellite HCHO retrievals from the Ozone Monitoring Instrument (OMI)—the NASA retrieval developed by the Smithsonian Astrophysical Observatory (SAO), and the European Union Quality Assurance for Essential Climate Variables (QA4ECV) retrieval—to evaluate three CMAQ configurations, spanning the summers of 2011 and 2016, with differing biogenic emissions inputs and chemical mechanisms. These CMAQ configurations capture the general spatial and temporal behavior of both satellite retrievals, but underestimate column HCHO, particularly in the western U.S. In the southeastern U.S., the comparison with OMI HCHO highlights differences in modeled meteorology and biogenic emissions even with differences in satellite retrievals. All CMAQ configurations show low daily correlations with OMI HCHO (r = 0.26–0.38), however, we find higher monthly correlations (r = 0.52–0.73), and the models correlate best with the OMI‐QA4ECV product. Compared to surface observations, we find improved agreement over a 24‐h period compared to afternoon‐only, suggesting daily HCHO amounts are captured with more accuracy than afternoon amounts. This work highlights the potential for synergistic improvements in modeling and satellite retrievals to support near‐surface HCHO estimates for the NATA and other applications.

中文翻译：

---

卫星甲醛支持模型评估

甲醛 (HCHO) 是一种被美国环境保护署 (US EPA) 列为危险污染物的已知致癌物质，通过遍布美国的监测网络进行测量 由于这些数据在空间和时间范围内受到限制，美国 EPA 的模型模拟社区多尺度空气质量 (CMAQ) 模型用于估计 EPA 国家空气毒物评估 (NATA) 的环境 HCHO 暴露。在这里，我们使用来自臭氧监测仪器 (OMI) 的卫星 HCHO 反演——由史密森天体物理天文台 (SAO) 开发的 NASA 反演和欧盟基本气候变量质量保证 (QA4ECV) 反演——来评估三个 CMAQ 配置，跨越 2011 年和 2016 年的夏季，具有不同的生物排放输入和化学机制。这些 CMAQ 配置捕获了两种卫星反演的一般空间和时间行为，但低估了 HCHO 列，特别是在美国西部 在美国东南部，与 OMI HCHO 的比较突出了模拟气象和生物排放的差异，即使卫星反演存在差异。所有 CMAQ 配置都显示出与 OMI HCHO (r  = 0.26–0.38)，然而，我们发现更高的月相关性 ( r  = 0.52–0.73)，并且模型与 OMI-QA4ECV 产品的相关性最好。与地表观测相比，我们发现与仅下午相比，24 小时内的一致性有所提高，这表明每日 HCHO 量的捕获比下午量更准确。这项工作突出了建模和卫星反演的协同改进潜力，以支持 NATA 和其他应用的近地表 HCHO 估计。