Morris Ralph E, McNally Dennis E, Tesche Thomas W, Tonnesen Gail, Boylan James W, Brewer Patricia
ENVIRON International Corporation, Novato, CA, USA.
J Air Waste Manag Assoc. 2005 Nov;55(11):1694-708. doi: 10.1080/10473289.2005.10464765.
The Visibility Improvement State and Tribal Association of the Southeast (VISTAS) is one of five Regional Planning Organizations that is charged with the management of haze, visibility, and other regional air quality issues in the United States. The VISTAS Phase I work effort modeled three episodes (January 2002, July 1999, and July 2001) to identify the optimal model configuration(s) to be used for the 2002 annual modeling in Phase II. Using model configurations recommended in the Phase I analysis, 2002 annual meteorological (Mesoscale Meterological Model [MM5]), emissions (Sparse Matrix Operator Kernal Emissions [SMOKE]), and air quality (Community Multiscale Air Quality [CMAQ]) simulations were performed on a 36-km grid covering the continental United States and a 12-km grid covering the Eastern United States. Model estimates were then compared against observations. This paper presents the results of the preliminary CMAQ model performance evaluation for the initial 2002 annual base case simulation. Model performance is presented for the Eastern United States using speciated fine particle concentration and wet deposition measurements from several monitoring networks. Initial results indicate fairly good performance for sulfate with fractional bias values generally within +/-20%. Nitrate is overestimated in the winter by approximately +50% and underestimated in the summer by more than -100%. Organic carbon exhibits a large summer underestimation bias of approximately -100% with much improved performance seen in the winter with a bias near zero. Performance for elemental carbon is reasonable with fractional bias values within +/- 40%. Other fine particulate (soil) and coarse particular matter exhibit large (80-150%) overestimation in the winter but improved performance in the summer. The preliminary 2002 CMAQ runs identified several areas of enhancements to improve model performance, including revised temporal allocation factors for ammonia emissions to improve nitrate performance and addressing missing processes in the secondary organic aerosol module to improve OC performance.
美国东南部能见度改善状况与部落协会（VISTAS）是负责管理美国雾霾、能见度及其他区域空气质量问题的五个区域规划组织之一。VISTAS第一阶段的工作对三个时段（2002年1月、1999年7月和2001年7月）进行了模拟，以确定用于第二阶段2002年年度模拟的最佳模型配置。利用第一阶段分析中推荐的模型配置，在覆盖美国大陆的36公里网格和覆盖美国东部的12公里网格上进行了2002年年度气象（中尺度气象模型[MM5]）、排放（稀疏矩阵算子核排放[SMOKE]）和空气质量（社区多尺度空气质量模型[CMAQ]）模拟。然后将模型估算值与观测值进行比较。本文介绍了2002年年度初始基础案例模拟的CMAQ模型初步性能评估结果。使用来自多个监测网络的特定细颗粒物浓度和湿沉降测量数据，展示了美国东部地区的模型性能。初步结果表明，硫酸盐的性能相当不错，分数偏差值一般在+/-20%以内。冬季硝酸盐被高估约+50%，夏季被低估超过-100%。有机碳在夏季表现出约-100%的较大低估偏差，冬季性能有很大改善，偏差接近零。元素碳的性能合理，分数偏差值在+/-40%以内。其他细颗粒物（土壤）和粗颗粒物在冬季表现出较大（80-150%）的高估，但夏季性能有所改善。2002年CMAQ的初步运行确定了几个需要改进的方面以提高模型性能，包括修订氨排放的时间分配因子以改善硝酸盐性能，以及解决二次有机气溶胶模块中缺失的过程以改善有机碳性能。
