Provençal Simon, Buchard Virginie, da Silva Arlindo M, Leduc Richard, Barrette Nathalie, Elhacham Emily, Wang Sheng-Hsiang
Département de géographie, Université Laval, Quebec City, Quebec, Canada.
Goddard Space Flight Center, National Aeronautics and Space Administration, Greenbelt, Maryland, USA.
Aerosol Air Qual Res. 2017 Jan;17(1):253-261. doi: 10.4209/aaqr.2016.04.0145. Epub 2017 Jan 1.
Version 1 of the NASA MERRA Aerosol Reanalysis (MERRAero) assimilates bias-corrected aerosol optical depth (AOD) data from MODIS-Terra and MODIS-Aqua, and simulates particulate matter (PM) concentration data to reproduce a consistent database of AOD and PM concentration around the world from 2002 to the end of 2015. The purpose of this paper is to evaluate MERRAero's simulation of fine PM concentration against surface measurements in two regions of the world with relatively high levels of PM concentration but with profoundly different PM composition, those of Israel and Taiwan. Being surrounded by major deserts, Israel's PM load is characterized by a significant contribution of mineral dust, and secondary contributions of sea salt particles, given its proximity to the Mediterranean Sea, and sulfate particles originating from Israel's own urban activities and transported from Europe. Taiwan's PM load is composed primarily of anthropogenic particles (sulfate, nitrate and carbonaceous particles) locally produced or transported from China, with an additional contribution of springtime transport of mineral dust originating from Chinese and Mongolian deserts. The evaluation in Israel produced favorable results with MERRAero slightly overestimating measurements by 6% on average and reproducing an excellent year-to-year and seasonal fluctuation. The evaluation in Taiwan was less favorable with MERRAero underestimating measurements by 42% on average. Two likely reasons explain this discrepancy: emissions of anthropogenic PM and their precursors are largely uncertain in China, and MERRAero doesn't include nitrate particles in its simulation, a pollutant of predominately anthropogenic sources. MERRAero nevertheless simulates well the concentration of fine PM during the summer, when Taiwan is least affected by the advection of pollution from China.
美国国家航空航天局（NASA）的现代-era再分析资料集-气溶胶再分析（MERRAero）版本1同化了来自MODIS-Terra和MODIS-Aqua的经偏差校正的气溶胶光学厚度（AOD）数据，并模拟了颗粒物（PM）浓度数据，以重现2002年至2015年底全球范围内一致的AOD和PM浓度数据库。本文的目的是针对世界上两个PM浓度相对较高但PM成分差异很大的地区（以色列和台湾地区），将MERRAero对细颗粒物PM浓度的模拟结果与地面测量值进行评估。以色列被主要沙漠环绕，其PM负荷的特点是矿物粉尘贡献显著，鉴于其靠近地中海，海盐颗粒有次要贡献，还有来自以色列自身城市活动以及从欧洲传输过来的硫酸盐颗粒。台湾地区的PM负荷主要由本地产生或从中国大陆传输过来的人为颗粒物（硫酸盐、硝酸盐和含碳颗粒物）组成，此外还有春季从中国和蒙古沙漠传输过来的矿物粉尘的贡献。在以色列进行的评估产生了良好的结果，MERRAero平均略微高估测量值6%，并重现了出色的逐年和季节性波动。在台湾地区的评估结果不太理想，MERRAero平均低估测量值42%。有两个可能的原因解释这种差异：中国的人为PM及其前体的排放很大程度上不确定，并且MERRAero在其模拟中不包括硝酸盐颗粒，而硝酸盐颗粒主要是人为来源的污染物。不过，MERRAero在夏季能很好地模拟细颗粒物PM的浓度，此时台湾地区受来自中国大陆的污染平流影响最小。
