Quantifying the uncertainty of inversion-derived ${\mathrm{CO}}_2$ surface fluxes and attributing the uncertainty to errors in either flux or atmospheric transport simulations continue to be challenges in the characterization of surface sources and sinks of carbon dioxide ( ${\mathrm{CO}}_2$ ). Despite recent studies inferring fluxes while using higher-resolution modeling systems, the utility of regional-scale models remains unclear when compared to existing coarse-resolution global systems. Here, we present an off-line coupling of the mesoscale Weather Research and Forecasting (WRF) model to optimized biogenic ${\mathrm{CO}}_2$ fluxes and mole fractions from the global Carbon Monitoring System inversion system (CMS-Flux). The coupling framework consists of methods to constrain the mass of ${\mathrm{CO}}_2$ introduced into WRF, effectively nesting our regional domain covering most of North America (except the northern half of Canada) within the CMS global model. We test the coupling by simulating Greenhouse gases Observing SATellite (GOSAT) column-averaged dry-air mole fractions ( ${\mathrm{XCO}}_2$ ) over North America for 2010. We find mean model-model differences in summer of ∼0.12 ppm, significantly lower than the original coupling scheme (from 0.5 to 1.5 ppm, depending on the boundary). While 85% of the ${\mathrm{XCO}}_2$ values are due to long-range transport from outside our North American domain, most of the model-model differences appear to be due to transport differences in the fraction of the troposphere below 850 hPa. Satellite data from GOSAT and tower and aircraft data are used to show that vertical transport above the Planetary Boundary Layer is responsible for significant model-model differences in the horizontal distribution of column ${\mathrm{XCO}}_2$ across North America.

中文翻译：

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碳监测系统通量反演框架内从全球到中尺度的总柱二氧化碳摩尔分数的大气模拟

量化反演衍生的不确定性 ${\mathrm{一氧化碳}}_2$ 表面通量以及将不确定性归因于通量或大气传输模拟中的误差仍然是表征表面二氧化碳源和二氧化碳汇的挑战（ ${\mathrm{一氧化碳}}_2$ ）。尽管最近有研究在使用更高分辨率的建模系统时推断出通量，但与现有的粗分辨率全球系统相比，区域尺度模型的效用仍不清楚。在这里，我们提出了中尺度天气研究和预报（WRF）模型与优化的生物成因的离线耦合 ${\mathrm{一氧化碳}}_2$ 全球碳监测系统反演系统（CMS-Flux）的通量和摩尔分数。耦合框架由约束质量的方法组成 ${\mathrm{一氧化碳}}_2$ 引入到WRF中，从而有效地将覆盖北美大部分地区（加拿大北半部除外）的区域区域嵌套在CMS全球模型中。我们通过模拟温室气体观测卫星（GOSAT）列平均干空气摩尔分数（ ${\mathrm{XCO}}_2$ ）在2010年的北美地区。我们发现夏季的平均模型模型差异约为0.12 ppm，大大低于原始的耦合方案（从0.5到1.5 ppm，取决于边界）。而85％ ${\mathrm{XCO}}_2$ 数值是由于我们北美地区以外的远距离运输所致，大多数模型-模型差异似乎是由于对流层中低于850 hPa的运输差异所致。来自GOSAT的卫星数据以及塔架和飞机的数据用于表明，行星边界层上方的垂直传输是造成圆柱水平分布中模型与模型差异的重要原因 ${\mathrm{XCO}}_2$ 在整个北美。