Wu Yao, Wen Bo, Ye Tingting, Huang Wenzhong, Liu Yanming, Gasparrini Antonio, Sera Francesco, Tong Shilu, Lavigne Eric, Roye Dominic, Achilleos Souzana, Ryti Niilo, Pascal Mathilde, Zeka Ariana, de'Donato Francesca, das Neves Pereira da Silva Susana, Madureira Joana, Mistry Malcolm, Armstrong Ben, Bell Michelle L, Schwartz Joel, Guo Yuming, Li Shanshan
Climate, Air Quality Research Unit, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia.
Environment & Health Modelling Lab, Department of Public Health, Environments and Society, London School of Hygiene & Tropical Medicine, London, UK.
Lancet Planet Health. 2025 Jul;9(7):101235. doi: 10.1016/S2542-5196(25)00062-2. Epub 2025 Apr 30.
Heat exposure poses a substantial public health threat. Increasing greenness has been suggested as a mitigation strategy due to its cooling effect and potential to modify the heat-mortality association. This study aimed to comprehensively estimate the effects of increased greenness on heat-related deaths.
We applied a multistage meta-analytical approach to estimate the potential reduction in global heat-related deaths by increasing greenness in the warm season in 2000-19 in 11 534 urban areas. We used the enhanced vegetation index (EVI) to indicate greenness and a random forest model to predict daily temperatures in counterfactual EVI scenarios. In the factual EVI scenarios, daily mortality and weather variables from 830 locations in 53 countries were extracted from the Multi-Country Multi-City Collaborative Research Network and used to assess heat-mortality associations. These associations were then extrapolated to each urban area under both factual and counterfactual EVI scenarios based on meta-regression models.
We estimated that EVI increased by 10% would decrease the global population-weighted warm-season mean temperature by 0·08°C, EVI increased by 20% would decrease temperature by 0·14°C, and EVI increased by 30% would decrease temperature by 0·19°C. In the factual scenario, 3 153 225 (2·48%) of 127 179 341 total deaths could be attributed to heat exposure. The attributable fraction of heat-related deaths (as a fraction of total deaths) in 2000-19 would decrease by 0·67 (95% empirical CI 0·53-0·82) percentage points in the 10% scenario, 0·80 (0·63-0·97) percentage points in the 20% scenario, and 0·91 (0·72-1·10) percentage points in the 30% scenario, compared with the factual scenario. South Europe was modelled to have the largest decrease in attributable fraction of heat-related mortality.
This modelling study suggests that increased greenness could substantially reduce the heat-related mortality burden. Preserving and expanding greenness might be potential strategies to lower ambient temperature and reduce the health impacts of heat exposure.
Australian Research Council and Australian National Health and Medical Research Council.
高温暴露对公众健康构成重大威胁。由于其降温作用以及改变高温与死亡率之间关联的潜力，增加城市绿化被提议作为一种缓解策略。本研究旨在全面评估绿化增加对与高温相关死亡的影响。
我们采用多阶段荟萃分析方法，以估算2000年至2019年期间11534个城市地区在暖季增加绿化可能使全球与高温相关死亡人数减少的情况。我们使用增强植被指数（EVI）来表示绿化程度，并使用随机森林模型预测在反事实EVI情景下的每日气温。在实际EVI情景中，从多国多城市合作研究网络中提取了53个国家830个地点的每日死亡率和天气变量，用于评估高温与死亡率之间的关联。然后，基于荟萃回归模型，将这些关联外推到实际和反事实EVI情景下的每个城市地区。
我们估计，EVI增加10%将使全球人口加权暖季平均气温降低0.08°C，EVI增加20%将使气温降低0.14°C，EVI增加30%将使气温降低0.19°C。在实际情景中，127179341例总死亡中的3153225例（2.48%）可归因于高温暴露。与实际情景相比，在EVI增加10%的情景下，2000年至2019年期间与高温相关死亡的归因比例（占总死亡的比例）将降低0.67（95%经验置信区间0.53 - 0.82）个百分点，在EVI增加20%的情景下降低0.80（0.63 - 0.97）个百分点，在EVI增加30%的情景下降低0.91（0.72 - 1.10）个百分点。模拟结果显示，南欧与高温相关死亡率的归因比例下降幅度最大。
这项建模研究表明，增加绿化可以大幅减轻与高温相关的死亡负担。保护和扩大绿化可能是降低环境温度以及减少高温暴露对健康影响的潜在策略。
澳大利亚研究理事会和澳大利亚国家卫生与医学研究理事会。
