The U.S. EPA (United States Environmental Protection Agency) is leveraging recent advances in meteorological modeling to construct an air quality modeling system to allow consistency from global to local scales. The Model for Prediction Across Scales‐Atmosphere (MPAS‐A or MPAS) has been developed by the National Center for Atmospheric Research (NCAR) as a global complement to the Weather Research and Forecasting model (WRF). Patterned after a regional coupled system with WRF, the Community Multiscale Air Quality (CMAQ) modeling system has been coupled within MPAS to explore global‐to‐local chemical transport modeling. Several options were implemented into MPAS for retrospective applications. Nudging‐based data assimilation was added to support continuous simulations of past weather to minimize error growth that exists with a weather forecast configuration. The Pleim‐Xiu land‐surface model, the Asymmetric Convective Model 2 boundary layer scheme, and the Pleim surface layer scheme were added as the preferred options for retrospective air quality applications with WRF. Annual simulations were conducted using this EPA‐enhanced MPAS configuration on two different mesh structures and compared against WRF. MPAS generally compares well with WRF over the conterminous United States. Errors in MPAS surface meteorology are comparable to WRF throughout the year. Precipitation statistics indicate MPAS performs slightly better than WRF. Solar radiation in MPAS is higher than WRF and measurements, suggesting fewer clouds in MPAS than WRF. Upper‐air meteorology is well‐simulated by MPAS, but errors are slightly higher than WRF. These comparisons lend confidence to use MPAS for retrospective air quality modeling and suggest ways it can be further improved in the future.

中文翻译：

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为全球回顾性空气质量建模建立跨尺度预测模型的适用性

美国 EPA（美国环境保护署）正在利用气象建模的最新进展来构建空气质量建模系统，以实现从全球到地方尺度的一致性。美国国家大气研究中心 (NCAR) 开发了跨尺度大气预测模型 (MPAS-A 或 MPAS)，作为天气研究和预报模型 (WRF) 的全球补充。以 WRF 的区域耦合系统为模式，社区多尺度空气质量 (CMAQ) 建模系统已与 MPAS 耦合，以探索全球到本地的化学传输建模。在 MPAS 中实施了几个选项，用于追溯应用。添加了基于微调的数据同化以支持对过去天气的连续模拟，以最大限度地减少天气预报配置中存在的误差增长。Pleim-Xiu 地表模型、不对称对流模型 2 边界层方案和 Pleim 表层方案被添加为 WRF 回顾性空气质量应用的首选选项。使用这种 EPA 增强型 MPAS 配置在两种不同的网格结构上进行年度模拟，并与 WRF 进行比较。在美国本土，MPAS 通常与 WRF 相媲美。MPAS 地面气象学的误差全年与 WRF 相当。降水统计表明 MPAS 的表现略好于 WRF。MPAS 中的太阳辐射高于 WRF 和测量值，表明 MPAS 中的云少于 WRF。MPAS 可以很好地模拟高空气象，但误差略高于 WRF。这些比较增强了使用 MPAS 进行回顾性空气质量建模的信心，并提出了未来可以进一步改进的方法。