在TEMPO NO2列密度中对偏差的全面分析通过潘多拉观测
Masoud Ghahremanloo1, Caroline Nowlan1, Gonzalo González Abad1
1Center for Astrophysics | Harvard & Smithsonian, Cambridge, MA, USA.
概括
卫星TEMPO显示在监测北美空气污染,特别是NO2的高度准确性. 它的表现最好是在晴朗的天空和中午观测时,与TROPOMI相似.
科学领域:
- 大气科学 大气科学
- 遥感 遥感 遥感 遥感
- 空气质量监测 空气质量监测
背景情况:
- 热带气体排放:污染监测 (TEMPO) 是一个先进的地球静止卫星仪器,用于观察北美空气污染物.
- 精确测量二氧化 (NO2) 对于了解空气质量和污染动态至关重要.
研究的目的:
- 为了评估TEMPO Level-3 NO2 (TOTNO2) 数据总列密度的偏差和准确性.
- 将TEMPO的NO2测量与地面的潘多拉观测和卫星TROPOMI进行比较.
主要方法:
- 对TEMPO TOTNO2数据与Pandora在2023年8月至2024年12月的地面测量数据进行分析.
- 在不同的云过门和太阳顶点角度 (SZAs) 下评估TEMPO的准确性.
- 对TEMPO验证结果与TROPOMI卫星数据进行比较.
主要成果:
- 在5%的云过门下,TEMPO可以实现高精度 (R: 0.86,IOA: 0.91,MABP: 23.1%),但随着云覆盖增加,精度会降低.
- 在10-20°的SZAs观察到最佳准确性,而更高的SZAs (70-80°) 显示可靠性降低.
- 在低NO2度 (+16%) 时,TEMPO表现出高度 (-31%) 的高估值和低估值,站到站的变化很大.
结论:
- 时间为监测NO2提供了有价值的数据集,其准确性取决于云层覆盖和太阳顶峰角度.
- 中午的观测结果与最小的云层覆盖产生最可靠的TEMPO NO2数据.
- 与潘多拉相比,TEMPO的验证性能与TROPOMI卫星的性能相当.
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