Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria, South Africa.
Laboratoire de l'Atmosphère et des Cyclones (LACy, UMR 8105 CNRS, Université de La Réunion, Météo-France), Saint-Denis de La Réunion, France.
Photochem Photobiol. 2020 Nov;96(6):1342-1349. doi: 10.1111/php.13308. Epub 2020 Jul 27.
Satellite estimates of surface ultraviolet A (UVA) (315-400 nm) from the Global Ozone Monitoring Experiment (GOME)-2 were compared to ground-based measurements at four stations in South Africa for 2015. The comparison of daily exposure and daily maximum irradiance was completed for all-sky and clear-sky conditions. There is a strong linear correlation between the satellite and ground-based data with a correlation coefficient (r) between 0.86 and 0.97 for all-sky conditions. However, at three of the stations the satellite data are underestimated compared to ground-based data with a mean bias error (MBE) between -8.7% and -20.6%. A seasonal analysis indicated that there is a link between the bias in ground-based and GOME-2 UVA and cloud fraction. Factors such as aerosols, surface albedo, altitude and data resolution may contribute to the underestimations found at the three sites. These results indicate that satellite estimates of surface UVA over South Africa do not exhibit the same behavior as other stations around the world and therefore require further validation.
利用全球臭氧监测实验（GOME）-2 卫星观测的地表紫外 A（UVA）（315-400nm）与南非 4 个地面站的测量结果进行了 2015 年的对比。对全天空和晴空条件下的日暴露量和日最大辐照度进行了对比。全天空条件下，卫星和地面数据之间存在很强的线性相关性，相关系数（r）在 0.86 到 0.97 之间。然而，与地面数据相比，卫星数据在 3 个站被低估了，平均偏差误差（MBE）在-8.7%到-20.6%之间。季节性分析表明，地面和 GOME-2 UVA 与云量之间存在联系。气溶胶、地表反照率、海拔和数据分辨率等因素可能导致这 3 个站点的低估。这些结果表明，南非地表 UVA 的卫星估算值与世界其他地区的其他站点表现出不同的行为，因此需要进一步验证。
