Abstract. An ensemble-variational inversion system is developed for the estimation of ammonia emissions using ammonia retrievals from the Cross-track Infrared Sounder (CrIS) for use in the Global Environmental Multiscale – Modelling Air quality and Chemistry (GEM-MACH) chemical weather model. A novel hybrid method to compare logarithmic retrieval parameters to model profiles is presented. Inversions for the monthly mean ammonia emissions over North America were performed for May to August 2016. Inversions using the hybrid comparison method increased ammonia emissions at most locations within the model domain, with total monthly mean emissions increasing by 11–41 %. The use of these revised emissions in GEM-MACH reduced biases with surface ammonia observations by as much as 25 %. The revised ammonia emissions also improved the forecasts of total (fine+coarse) ammonium and nitrate and ammonium wet deposition, with biases decreasing by as much as 13 %, but did not improve the forecasts of just the fine components of ammonium and nitrate. An additional area of 1.3 × 10⁵ km² of upland forests in Canada were estimated to exceed the ecosystem's critical load due to the changes in ammonia deposition from the inversion. A comparison of biases resulting from inversions using different comparison methods shows favourable results for the hybrid comparison method.

中文翻译：

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使用 CrIS 卫星氨反演估算氨排放的集合变分反演系统

摘要。开发了一个集合变分反演系统，用于使用来自跨径红外测深仪 (CrIS) 的氨气反演估算氨气排放，以用于全球环境多尺度 - 空气质量和化学建模 (GEM-MACH) 化学天气模型。提出了一种将对数检索参数与模型配置文件进行比较的新混合方法。2016 年 5 月至 8 月对北美的月平均氨排放量进行了反演。使用混合比较方法的反演增加了模型域内大多数位置的氨气排放量，总月平均排放量增加了 11-41%。在 GEM-MACH 中使用这些修订后的排放量减少了多达 25% 的表面氨观测偏差。修订后的氨排放量也改进了对总（细+粗）铵盐和硝酸盐以及铵盐湿沉降的预测，偏差减少了 13%，但并没有改进仅对铵盐和硝酸盐的细组分的预测。1.3 × 10 的附加面积由于反演引起的氨沉积变化，估计加拿大⁵公里²的高地森林超过了生态系统的临界负荷。使用不同比较方法对反演产生的偏差进行比较显示了混合比较方法的有利结果。