Ph.D. Workshop iPlus：Impact of Corporate Green Bond Issuance on Air Pollution Reduction in Asia
How effective are corporate green bonds in mitigating air pollution in Asia? On October 15 2024, the CSS held the “CSS Ph.D. Workshop” for Natjanan Chujit, a third-year master student of NCCU IMES, to present her thesis research. The workshop was chaired by Professor Huey-Lin Lee from the Department of Economics, CSS. Prof. Ken Itakura from the Faculty of Economics, Nagoya City University, Japan, was invited to discuss this research paper, via GoogleMeet.
Natjanan’s study examines the effectiveness of corporate green bonds in reducing air pollution across 28 Asian cities from 2018 to 2023. It utilizes a detailed dataset combining green bond issuance data with various air quality metrics, including PM2.5, PM10, sulfate, sulfur dioxide, organic carbon, and black carbon. By applying a high-dimensional fixed effects (HDFE) regression model with multiple time lags, the study assesses long-term effects of the corporate green bonds, noting that funded projects often take over a year to manifest pollution reduction. The results show a significant 14-month lag in reductions of sulfate, black carbon, and organic carbon, while impacts on PM2.5, PM10, and sulfur dioxide are less substantial. Regional variations in urbanization and industrialization levels may complicate the effectiveness of these projects. Natjanan’s research advances understanding of how targeted financial investments can yield environmental and health benefits, while also addressing greenwashing concerns, where companies may overstate their environmental impact.
Prof. Ken Itakura noted that Natjanan’s thesis provided valuable insights into the ongoing debate regarding the effectiveness of corporate green bonds, an area that remains relatively underexplored, especially within developing Asian economies.. Prof. Itakura suggested some alternative model specifications to better capture the impact of green bonds. The comments and feedback from Prof. Itakura sparked further research ideas and new approaches for analyzing this important topic.
The workshop audience, representing various disciplines, engaged in a lively discussion following Natjanan’s talk and Prof. Itakura’s discussion. Several students raised questions about what drives companies to issue green bonds. An international student from NCCU IMPIS, with a European perspective, voiced particular concern about greenwashing—a pressing and high-priority issue in Europe today.
In concluding the workshop, Professor Huey-Lin Lee encouraged participants to further pursue research on the critical issue of air pollution mitigation in Asia. Prof. Lee hoped that the developing economies could strike a good balance between economic growth and environmental sustainability. Research like Natjanan’s study plays a vital role in advancing this goal and can contribute significantly to solving real-world environmental challenges.
