Urban overheating affects the energy, health, power, survivability and environmental quality of cities. We calculated the magnitude of overheating in Sydney, Australia, at close to 9°C, which causes a cooling penalty of up to 16% and an increase in the indoor overheating levels of up to 56%. We developed and evaluated eight heat mitigation scenarios based on the use of reflective surfaces, additional greenery, an increase in the evapotranspiration rate and several combinations of these factors. We estimated that mitigation can decrease the peak ambient temperature by up to 2.9°C, reduce the maximum annual cooling consumption by up to 1.5 TWh, decrease the CO2 emissions by as much as 1.21 MT CO₂, reduce indoor overheating by up to 80%, decrease the heat-related morbidity by 1.07-1.49, and decrease the heat-related mortality anomaly by as much as 1.39 per 100,000 citizens. We estimated the associated water penalty range to be between 80 and 100 Gl/year or between 13 and 16.7% of the water consumption in Sydney.

城市过热会影响城市的能源，健康，能源，生存能力和环境质量。我们计算了接近9°C的澳大利亚悉尼的过热程度，这将导致最高16％的降温损失以及室内最高56％的室内过热度增加。我们基于反射面的使用，额外的绿化，蒸散速率的提高以及这些因素的几种组合，开发并评估了八种减热方案。我们估计，缓解措施可将最高峰值环境温度降低2.9°C，将最大年度制冷量降低多达1.5 TWh，将CO2排放量降低多达1.21 MT CO ₂，最多可将室内过热降低80％，将与热相关的发病率降低1.07-1.49，并将与热相关的死亡率异常降低多达每10万人1.39。我们估计相关的水罚范围为每年80至100 Gl，或悉尼耗水量的13至16.7％。