Circulation-regulated impacts of aerosol pollution on urban heat island in Beijing

Abstract. Unprecedented urbanization in China has led to serious urban heat island (UHI) issues, exerting intense stress on residents. Based the observed temperature and PM2.5 concentrations Beijing over 2016–2020, we find diverse influences of aerosol pollution intensity (UHII) under different circulations. When northerly winds are prevalent Beijing, UHII tends be much higher both daytime nighttime it is less affected by concentrations. However, when southerly westerly dominant rural significantly reduced pollution. Using coupled aerosol-radiation weather simulations, demonstrate underlying physical mechanism which associated with local circulation resulting spatial distribution aerosols. Our results also highlight role black carbon aggravating UHI, especially during nighttime. It could thus targeted for cooperative management islands