摘要1：Reductions in ambient pollution have been taken as an indisputable "silver lining" to the COVID-19 Pandemic. Indeed, worldwide economic contraction induced by COVID-19 lockdowns should generate global air quality improvements ceteris paribus, including to China's notoriously-poor air quality. We analyze China's official pollution monitor data and account for the large, recurrent improvement in air quality following Lunar New Year (LNY), which essentially coincided with lock-downs in 2020. With the important exception of NO2, China's air quality improvements in 2020 are smaller than we should expect near the pandemic's epicenter: Hubei province. Compared with LNY improvements experienced in 2018 and 2019 in Hubei, we see smaller improvements in SO2 while ozone concentrations increased in both relative and absolute terms (roughly doubling). Similar patterns are found for the six provinces neighboring Hubei. We conclude that COVID-19 had ambiguous impacts on China's pollution, with evidence of relative deterioration in air quality near the Pandemic's epicenter.  

 

摘要2： China emits twice as much CO2 as the United States. Launched in seven regions in 2013-2014, China’s pilot carbon trading programs cover roughly 7% of China’s CO2 emissions. These market-based policies offer the best existing evidence as to whether the national carbon trading program starting in 2021 will curb emissions. Here, we analyze changes in air quality using visibility measures from weather stations. We find the pilot programs improved local air quality and this was likely a co-benefit of reduced carbon emissions. However, these improvements were modest and there is some evidence of pollution leakage to the non-pilot regions.   

张爽，中欧国际工商学院经济学教授。在加入中欧之前，她任教于美国科罗拉多大学博尔德分校经济系并获终身教职。她还曾在斯坦福大学的斯坦福经济政策研究所担任博士后。她毕业于康奈尔大学并获得经济学博士学位，在复旦大学获得经济学硕士学位。

张教授的研究兴趣主要集中在能源与环境经济学、健康经济学、以及中国经济。她的论文多次发表于国际顶级学术期刊，包括政治经济学期刊 (Journal of Political Economy), 发展经济学期刊 (Journal of Development Economics), 美国国家科学院院刊 (Proceedings of the National Academy of Sciences) 等。张教授的研究成果广为权威媒体所报道，包括华尔街日报、经济学人，福布斯、彭博社等。张教授还曾连续四年担任美国国家科学基金重大研究项目的主要负责人。