Jungho Im

Abstract The 2025 Los Angeles wildfires highlighted growing risks from climate-driven extremes and the need for reliable wildfire forecasting beyond short lead times. Although the European Centre for Medium-Range Weather Forecasts provides global fire weather index forecasts, these products are primarily designed for long-range climate outlooks, and their practical effectiveness remains uncertain in regions with limited local forecasting infrastructure.

Abstract Urban morphology and background climate are evolving drivers of the urban heat island (UHI) effect, yet the thermal influence of surrounding urban structure and its coupling with climate remain elusive. Here, we show that climate and morphology jointly shape global urban heat. Using a six-class urban typology, long-term climatology, and machine learning, we quantify the thermal influence of surrounding urban structure and project future urban heat across 2,213 cities.

The legend colors for NO2 and O3 were interchanged in Figure 3. This has been corrected in the revised figure. The legends in the related time series plots have also been corrected in Figures S16 and S17 in the Supporting Information, and the Supporting Information has been updated accordingly. The hourly O3 time-series and corresponding statistics in Figure 3 (BTH) and Supporting Information Figures S16 (YRD) and S17 (SMA) have been corrected. The underlying model predictions remain unchanged.