Starting in January 2020, the novel coronavirus, now known as acute respiratory syndrome coronavirus (SARS-CoV-2) and the disease that it causes (COVID-19) has had significant impacts on human health, the environment, and the economy globally. The rapid lockdown that occurred as well as its well documented timing allows for an unprecedented opportunity to examine the impact of air pollution from densely populated regions has on adjacent and pristine environments. Here, we use in situ and satellite observations to show that there was a step function decrease in two key indicators of air quality, nitrogen dioxide and airborne particulates, in locations within the Indo-Gangetic Plan (IGP) as a result of the Spring 2020 lockdown. Based on anomaly patterns, we find a dipole response with a statistically significant reduction in air pollution along the western IGP and Himalaya and an increase in air pollution in the eastern IGP and Himalaya. We show that spatial variability in the reductions in economic activity across northern India and the adjoining countries of Nepal, Pakistan, and Bangladesh contributed to this dipole as did a persistent atmospheric circulation anomaly across the region during the lockdown.

中文翻译：

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印度恒河平原 COVID-19 封锁对喜马拉雅山空气质量的影响


自 2020 年 1 月开始，新型冠状病毒（现称为急性呼吸综合征冠状病毒 (SARS-CoV-2)）及其引起的疾病 (COVID-19) 对全球人类健康、环境和经济产生了重大影响。迅速发生的封锁及其有据可查的时间安排为研究人口稠密地区的空气污染对邻近和原始环境的影响提供了前所未有的机会。在此，我们利用现场观测和卫星观测结果表明，由于 2020 年春季的影响，印度恒河计划 (IGP) 范围内的两个关键空气质量指标（二氧化氮和空气颗粒物）出现阶跃函数下降封锁。根据异常模式，我们发现偶极子响应，IGP 西部和喜马拉雅地区空气污染统计显着减少，而 IGP 东部和喜马拉雅地区空气污染增加。我们发现，印度北部以及毗邻的尼泊尔、巴基斯坦和孟加拉国经济活动减少的空间变异性以及封锁期间该地区持续的大气环流异常也导致了这种偶极子的产生。