XCH\u2084 Measurements for High-Resolution Methane Concentration Mapping

The dataset utilized in this study corresponds to the year 2019 (all months) and covers an extensive region within the Mediterranean Basin. This particular year was selected to investigate seasonal variations in column-averaged dry-air mole fraction of methane (XCH\u2084), providing insights into methane dynamics over different climatic periods.Furthermore, to assess long-term trends in methane emissions in the world, data from four distinct years\u20142019 and 2021\u2014were analyzed, and they cover 4 months (January, April, July, and October). By comparing these periods, we aimed to identify potential increases in atmospheric XCH\u2084 concentrations and detect emerging emission patterns. Specific intervals within these years were carefully selected based on data quality, spatial coverage, and relevance to the research objectives, ensuring robust and reliable methane estimations.For the purposes of this study, two different geographical domains were defined:A global study area, encompassing longitudes from 180\u00b0W to 180\u00b0E and latitudes from 90\u00b0S to 90\u00b0N.A regional study area, focused on longitudes between 1\u00b0E and 40\u00b0E and latitudes between 20\u00b0N and 50\u00b0N, covering a substantial portion of the Mediterranean region.This approach allowed for a comprehensive analysis, integrating both broad-scale atmospheric observations and more localized assessments to enhance the understanding of methane distribution and its temporal evolution.

本研究使用的数据集对应2019年（全年各月），覆盖地中海盆地内的广阔区域。选择该年份旨在研究甲烷柱平均干空气摩尔分数（column-averaged dry-air mole fraction of methane）的季节变化，以解析不同气候周期下的甲烷动力学特征。此外，为评估全球甲烷排放的长期趋势，本研究还分析了4个不同年份的数据（其中涵盖2019年与2021年），这些数据覆盖了1月、4月、7月和10月四个月份。通过对比上述时段，本研究旨在识别大气XCH₄浓度的潜在增长，并检测新出现的排放模式。研究人员基于数据质量、空间覆盖范围以及与研究目标的相关性，精心筛选了上述年份中的特定时段，以确保甲烷估算结果的稳健性与可靠性。

本研究定义了两类地理研究域：
1. 全球研究区域：经度范围为180°W至180°E，纬度范围为90°S至90°N。
2. 区域研究区域：聚焦于经度1°E至40°E、纬度20°N至50°N的范围，覆盖地中海地区的大部分区域。

该研究方法可实现全面分析，整合大范围大气观测与局域评估，以加深对甲烷分布及其时间演变的理解。