Satellites provide global coverage for monitoring atmospheric greenhouse gases, crucial for understanding global climate dynamics. However, their temporal and spatial resolutions fall short in detecting urban-scale variations. To enhance satellite reliability over urban areas, this study presents the first comprehensive analysis of long-term observations of column-averaged dry air mole fractions of CO₂, CH₄, and CO (XCO₂, XCH₄, XCO) using two ground-based fourier transform infrared spectrometers, EM27/SUNs, in a megacity. With over 2 years of observations, our study shows that EM27/SUN measurements can effectively capture the daily and seasonal variability of XCO₂, XCH₄, and XCO over Seoul, a megacity with complex topography and various emission sources. In addition, we use the advantage of having multiple greenhouse gas satellites targeting Seoul to compare with the EM27/SUNs. Our study highlights the importance of EM27/SUN observations in Seoul to identify the need for improvements in satellites to monitor greenhouse gas behaviors and emissions in urban areas.

中文翻译：

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使用便携式地面光谱仪对首尔温室气体观测卫星的性能进行比较


卫星提供全球覆盖来监测大气温室气体，这对于了解全球气候动态至关重要。然而，它们的时间和空间分辨率不足以检测城市规模的变化。为了提高城市地区卫星的可靠性，本研究首次对 CO ₂ 、 CH ₄ 和 CO 的柱平均干燥空气摩尔分数的长期观测进行综合分析（ XCO ₂ 、 XCH ₄ 、 XCO) 在大城市使用两台地面傅里叶变换红外光谱仪 EM27/SUN。经过两年多的观察，我们的研究表明，EM27/SUN 测量可以有效捕捉首尔这个大城市的 XCO ₂ 、 XCH ₄ 和 XCO 的日变化和季节变化。地形复杂，排放源多样。此外，我们还利用拥有多颗以首尔为目标的温室气体卫星的优势来与 EM27/SUN 进行比较。我们的研究强调了首尔 EM27/SUN 观测的重要性，以确定改进卫星监测城市地区温室气体行为和排放的必要性。