To study emissions of CO₂ in the Baltimore, MD‐Washington, D.C. (Balt‐Wash) area, an aircraft campaign was conducted in February 2015, as part of the Fluxes of Atmospheric Greenhouse‐Gases in Maryland (FLAGG‐MD) project. During the campaign, elevated mole fractions of CO₂ were observed downwind of the urban center and local power plants. Upwind flight data and Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model analyses help account for the impact of emissions outside the Balt‐Wash area. The accuracy, precision, and sensitivity of CO₂ emissions estimates based on the mass balance approach were assessed for both power plants and cities. Our estimates of CO₂ emissions from two local power plants agree well with their Continuous Emissions Monitoring Systems (CEMS) records. For the 16 power plant plumes captured by the aircraft, the mean percentage difference of CO₂ emissions was −0.3%. For the Balt‐Wash area as a whole, the 1𝜎 CO₂ emission rate uncertainty for any individual aircraft‐based mass balance approach experiment was ±38%. Treating the mass balance experiments, which were repeated seven times within 9 days, as individual quantifications of the Balt‐Wash CO₂ emissions, the estimation uncertainty was ±16% (standard error of the mean at 95% CL). Our aircraft‐based estimate was compared to various bottom‐up fossil fuel CO₂ (FFCO₂) emission inventories. Based on the FLAGG‐MD aircraft observations, we estimate 1.9 ± 0.3 MtC of FFCO₂ from the Balt‐Wash area during the month of February 2015. The mean estimate of FFCO₂ from the four bottom‐up models was 2.2 ± 0.3 MtC.

中文翻译：

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马里兰州大气温室气体的通量（FLAGG-MD）：马里兰特区华盛顿-巴尔的摩的二氧化碳排放量

为了研究马里兰州华盛顿特区巴尔的摩市（巴尔什市）地区的CO ₂排放量，作为马里兰大气温室气体通量（FLAGG‐MD）项目的一部分，于2015年2月开展了一次飞机运动。在竞选期间，在市中心和当地发电厂的顺风处观察到了较高的CO ₂摩尔分数。迎风飞行数据和混合单粒子拉格朗日综合轨迹（HYSPLIT）模型分析有助于说明Balt-Wash区域以外的排放影响。在电厂和城市中，都基于质量平衡方法评估了CO ₂排放估算的准确性，准确性和敏感性。我们对CO _2的估计两个当地发电厂的排放与他们的连续排放监控系统（CEMS）记录非常吻合。对于飞机捕获的16个电厂烟柱，CO ₂排放的平均百分比差为-0.3％。对于整个Balt-Wash地区，任何基于飞机的质量平衡方法实验的1𝜎 CO ₂排放率不确定度均为±38％。处理质量平衡实验（在9天内重复进行7次）作为Balt-Wash CO ₂排放量的单独量化，估计不确定度为±16％（95％CL时平均值的标准误）。我们将基于飞机的估计值与各种自下而上的化石燃料CO ₂（FFCO ₂）排放清单。根据FLAGG-MD飞机的观测，我们估计2015年2月Balt-Wash地区的FFCO ₂为1.9±0.3 MtC 。四个自下而上模型的FFCO ₂的平均估计值为2.2±0.3 MtC。