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疫情期间全球各地一次排放大幅削减,而臭氧等二次污染的响应则存在着区域间差异.结合地面和卫星观测发现,同在氮氧化物大幅下降的情况下,臭氧在东亚和欧洲呈现出可达14ppb的上升信号,而北美则下降为主(约2-4ppb).我们结合气象分析和臭氧敏感性进一步讨论了臭氧响应差异性的原因,一方面受臭氧与前体物间关系的影响;另一方面来自于气象,尤其是温度.研究明晰了人为排放,化学和气象三者的内在关联,强调了在臭氧控制过程中考虑前体物削减和气象条件协同的重要性.“,”The explosive spread of the 2019 novel coronavirus(COVID-19)provides a unique chance to rethink the rela-tionship between human activity and air pollution.Though related studies have revealed substantial reductions in primary emissions,obvious differences do exist in the responses of secondary pollutants,like ozone(O3)pol-lution.However,the regional disparities of O3 responses and their causes have still not been fully investigated.To better elucidate the interrelationship between anthropogenic emissions,chemical production,and meteoro-logical conditions,O3 responses caused by lockdowns over different regions were comprehensively explored at a global scale.Observational signals of air-quality change were derived from multi-year surface measurements and satellite retrievals.With similar substantial drops in nitrogen dioxide(NO2),ozone shows rising signals in most areas of both East Asia and Europe,even up to～14 ppb,while a non-negligible declining signal exists in North America,by about 2-4 ppb.Furthermore,the drivers behind the different O3 responses are discussed based on meteorological analysis and O3 sensitivity diagnosis.On the one hand,O3 responses to NO2 declines can be affected by the primary dependence on its precursors.On the other hand,it is also highly dependent on meteorological factors,especially temperature.Our study further highlights the great importance of taking into consideration both the regional disparities and synergistic effects of precursor reductions and meteorological influence for scientific mitigation of O3 pollution.