Concurrent heat stress and air pollution episodes by considering future projection of climate change.

The simultaneous effect of heat stress and air pollutants such as ozone can cause many health issues in cities. The situation exacerbates in the context of climate change and temperature rise. Furthermore, ground-level ozone, worsened by climate change, needs investigation for effective management. Therefore, this study projects heat stress and ozone levels in two Coupled Model Intercomparison Project Phase 6 (CMIP6) climate scenarios, SSP245 and SSP585. Results indicate heightened heat stress with increased ozone levels, especially in severe climate scenarios like SSP585. Besides, the study shows that in the SSP245 and SSP585 scenarios, the seasonal shift of high Heat Index (HI) values as well as high ozone concentrations is happening toward the previous months of June-July-August (JJA). High values in the HI classification and the Maximum Daily 8-hour average (MDA8) ozone happen sooner in the March-April-May (MAM) months than the expected JJA months. Furthermore, in the SSP585 scenario, the HI classification above 105 (very hot equal to danger category) is 10% high in all months in comparison to the SSP245 scenario. The study emphasizes the importance of understanding the interactions between heat stress and ozone pollution for implementing effective adaptation and mitigation measures.