Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, 55128, Germany.
School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
Nat Commun. 2020 Jan 28;11(1):447. doi: 10.1038/s41467-020-14375-0.
Non-methane hydrocarbons (NMHCs) such as ethane and propane are significant atmospheric pollutants and precursors of tropospheric ozone, while the Middle East is a global emission hotspot due to extensive oil and gas production. Here we compare in situ hydrocarbon measurements, performed around the Arabian Peninsula, with global model simulations that include current emission inventories (EDGAR) and state-of-the-art atmospheric circulation and chemistry mechanisms (EMAC model). While measurements of high mixing ratios over the Arabian Gulf are adequately simulated, strong underprediction by the model was found over the northern Red Sea. By examining the individual sources in the model and by utilizing air mass back-trajectory investigations and Positive Matrix Factorization (PMF) analysis, we deduce that Red Sea Deep Water (RSDW) is an unexpected, potent source of atmospheric NMHCs. This overlooked underwater source is comparable with total anthropogenic emissions from entire Middle Eastern countries, and significantly impacts the regional atmospheric chemistry.
非甲烷烃（NMHCs），如乙烷和丙烷，是重要的大气污染物和对流层臭氧的前体，而中东地区由于广泛的石油和天然气生产，是全球排放的热点地区。在这里，我们将对在阿拉伯半岛周围进行的现场烃类测量与包括当前排放清单（EDGAR）和最先进的大气环流和化学机制（EMAC 模型）的全球模型模拟进行比较。虽然对阿拉伯湾上空高混合比的测量得到了很好的模拟，但模型对北红海地区的预测值明显偏低。通过检查模型中的个别源，并利用空气团后向轨迹研究和正定矩阵因子分析（PMF 分析），我们推断红海深部水（RSDW）是大气 NMHCs 的一个意外的、强大的来源。这个被忽视的水下源与整个中东地区的人为总排放量相当，对区域大气化学有重大影响。
