Abstract Anthropogenic climate change has been increasingly confirmed by weather observation and scientific literature in recent decades. Atmospheric stability, which has strong effects on vertical mixing of air pollutants and thus air quality, may be affected under climate change. This study aims to statistically assess the impacts of climate change alone on the future air quality in the Pearl River Delta region in the near future (2030–2039) and the far future (2090–2099) under two Representative Concentration Pathways (RCP) scenarios, i.e., RCP 4.5 and RCP 8.5, based on the future surface and upper level meteorological data projected by one regional climate model (RCM): WRF, and by four general circulation models (GCMs): CanESM2, MIROC, MRI-CGCM3 and MPI-ESM-LR. The arithmetic means of projections reveal an increase in the levels of air pollutants [ozone (O3), respirable suspended particulates (RSP) and sulphur dioxide (SO2)] in various seasons, even though a decrease is projected to occur in June-July-August. These changes in projected mean concentration are more significant in the far future, and under the RCP8.5 scenario. Among difference meteorological variables, surface temperature is most associated with the projected change in the three pollutants, with a range from 56.9% to 65.2% in all seasons and for all pollutants, relative to all contributions in RCP8.5 for example. Other notable associations include positive effects of vertical temperature gradient and the temperature–dew point difference on pollutant concentration. We found an increase in frequency of high pollution levels in December–January–February and March–April–May, as the occurrence proportion of pollutant concentration greater than the recent 95th percentile is 9.5%–9.6% and 6.4%–9.2%, respectively. We conclude that climate change alone is projected to have significant effect on air quality in the Pearl River Delta region in future, implying the necessity of more stringent air pollutant emission control policies to mitigate air pollution in the future.

中文翻译：

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气候变化下大气条件对珠江三角洲地区空气质量影响的预测

摘要 近几十年来，天气观测和科学文献越来越多地证实了人为气候变化。大气稳定性对空气污染物的垂直混合和空气质量有很大影响，可能会受到气候变化的影响。本研究旨在统计评估气候变化对珠江三角洲地区近期（2030-2039）和远期（2090-2099）两种代表性浓度路径（RCP）情景下未来空气质量的影响，即 RCP 4.5 和 RCP 8.5，基于一个区域气候模型 (RCM)：WRF 和四个大环流模型 (GCM)：CanESM2、MIROC、MRI-CGCM3 和 MPI 预测的未来地表和高层气象数据-ESM-LR。推算的算术平均值显示，不同季节的空气污染物 [臭氧 (O3)、可吸入悬浮颗粒物 (RSP) 和二氧化硫 (SO2)] 的水平有所增加，尽管预计 6-7 月会有所减少——八月。在遥远的未来，以及在 RCP8.5 情景下，预计平均浓度的这些变化更为显着。在不同的气象变量中，地表温度与三种污染物的预测变化最相关，所有季节和所有污染物的变化范围为 56.9% 至 65.2%，例如相对于 RCP8.5 中的所有贡献。其他值得注意的关联包括垂直温度梯度和温度-露点差异对污染物浓度的积极影响。我们发现12-1-2月和3-4-5月高污染水平频率增加，污染物浓度大于最近95%的发生比例分别为9.5%-9.6%和6.4%-9.2% . 我们的结论是，预计未来仅气候变化就会对珠江三角洲地区的空气质量产生重大影响，这意味着未来有必要采取更严格的空气污染物排放控制政策来缓解空气污染。