Basaglia Piero, Grunau Jonas, Drupp Moritz A
Department of Economics, University of Hamburg, 20146 Hamburg, Germany.
Center for Earth System Research and Sustainability, 20146 Hamburg, Germany.
Proc Natl Acad Sci U S A. 2024 Jul 9;121(28):e2319908121. doi: 10.1073/pnas.2319908121. Epub 2024 Jul 1.
Mitigating greenhouse gas emissions and reducing air pollution represent two pressing and interwoven environmental challenges. While international carbon markets, such as the European Union emissions trading system (EU ETS), have demonstrated their effectiveness in curbing carbon emissions (CO[Formula: see text]), their indirect impact on hazardous co-pollutants remains understudied. This study investigates how key toxic air pollutants-sulfur dioxide (SO[Formula: see text]), fine particulate matter (PM[Formula: see text]), and nitrogen oxides (NO[Formula: see text])-evolved after the introduction of the EU ETS with a comparative analysis of regulated and unregulated sectors. Leveraging the generalized synthetic control method, we offer an ex post analysis of how the EU ETS and concurrent emission standards may have jointly generated sizable pollution reductions in regulated sectors between 2005 and 2021. We provide an aggregate assessment that these pollution reductions could translate into large health co-benefits, potentially in the hundreds of billions of Euros, even when bounding the effect of emission standards. These order-of-magnitude estimates underscore key implications for policy appraisal and motivate further microlevel research around the health co-benefits of carbon abatement.
减轻温室气体排放和减少空气污染是两个紧迫且相互交织的环境挑战。虽然国际碳市场，如欧盟排放交易体系（EU ETS），已证明其在遏制碳排放（CO₂）方面的有效性，但其对有害协同污染物的间接影响仍未得到充分研究。本研究通过对受监管和不受监管部门的比较分析，调查了欧盟排放交易体系引入后关键有毒空气污染物——二氧化硫（SO₂）、细颗粒物（PM₂.₅）和氮氧化物（NOₓ）的变化情况。利用广义合成控制方法，我们对2005年至2021年期间欧盟排放交易体系和同期排放标准如何在受监管部门共同实现大幅污染减排进行了事后分析。我们提供了一项总体评估，即即使在限定排放标准影响的情况下，这些污染减排也可能转化为巨大的健康协同效益，潜在价值可能达数千亿欧元。这些数量级估计凸显了对政策评估的关键影响，并促使围绕碳减排的健康协同效益开展进一步的微观层面研究。
