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This paper also addresses the contribution of urban land use change to near-surface air temperature during the summer extreme heat events of the early 21 st century in the Beijing-Tianjin-Hebei metropolitan area.This study uses the Weather Research Forecasting (WRF) model with a single urban canopy model and the newest actual urban cover datasets.The results show that urban land use characteristics that have evolved over the past ~20 years in the Beijing-Tianjin-Hebei metropolitan area have had a significant impact on the extreme temperatures occurring during extreme heat events.Simulations show that new urban development has caused an intensification and expansion of the areas experiencing extreme heat waves with an average increase in temperature of approximately 0.60 ℃.This change is most obvious at night with an increase up to 0.95 ℃, for which the total contribution of anthropogenic heat is 34%.We also simulate the effects of geo-engineering strategies increasing the albedo of urban roofs, an effective way of reducing the urban heat island, which can reduce the urban mean temperature by approximately 0.51 ℃ and counter approximately 80% of the heat wave results from urban sprawl during the last 20 years.We proposed that white roofs may be an effective strategy to complement urban heat wave mitigation efforts as a way of further slowing the rate of global temperature increase in response to continued greenhouse gas emissions.