Exact assessment of urban atmospheric CO₂ enhancement, which is higher than background CO₂ concentrations, is critical to mitigate carbon emissions in the city. However, ground-based atmospheric CO₂ measurements covering the diverse landscape across the city are still limited. This study utilizes the column integrated CO₂ concentration (XCO₂) data obtained from the NASA Orbiting Carbon Observatory-2 (OCO-2) to evaluate urban CO₂ enhancements over Seoul Capital Area (SCA) of South Korea for the period 2014–2018. In this study, Jirisan National Park (JNP), which is the cleanest area on the same orbit track with SCA, is defined as the background area considering its strong vegetation activity and low anthropogenic carbon emissions. By comparing XCO₂ between SCA and JNP based on wind speed, we find an apparent increase in XCO₂ by 1.71 to 2.21 ppm over SCA only on the days with wind speed less than 4 m s⁻¹. Strong wind speed (e.g., over 4 m s⁻¹) disrupts the identification of XCO₂ enhancements over SCA due to atmospheric mixing between SCA and JNP. In addition, we compare estimated XCO₂ differences between SCA and JNP from OCO-2 with other low-resolution data. This increase in XCO₂ over SCA is only observed in OCO-2. Overall, our results suggest that high-resolution satellite remote sensing of XCO₂ constrained by wind speed has strong potential to open up the possibility of identifying atmospheric CO₂ enhancements in the city where ground-based observations are limited.

准确评估城市大气中CO _2的增加量要高于背景CO ₂浓度，这对于减轻城市的碳排放至关重要。但是，覆盖整个城市多样景观的地面大气CO ₂测量仍然有限。这项研究利用从NASA轨道碳观测站2（OCO-2）获得的柱综合CO ₂浓度（XCO ₂）数据来评估城市CO ₂2014-2018年期间韩国首尔首都地区（SCA）的改进。在这项研究中，吉里森国家公园（JNP）是与SCA在同一轨道上最干净的区域，考虑到其强烈的植被活动和低的人为碳排放，被定义为背景区域。通过基于风速比较SCA和JNP之间的XCO ₂，我们发现仅当风速小于4 m s ^-1时，XCO ₂才比SCA明显增加1.71至2.21 ppm 。由于SCA和JNP之间的大气混合，强风速（例如，超过4 m s ^-1）破坏了SCA上XCO ₂增强的识别。另外，我们比较估计的XCO ₂OCO-2的SCA和JNP与其他低分辨率数据之间的差异。XCO ₂超过SCA的增加仅在OCO-2中观察到。总体而言，我们的结果表明，受风速限制的XCO ₂高分辨率卫星遥感具有巨大的潜力，可以开辟出在地面观测受限的城市中识别大气CO ₂增强的可能性。