SYDNEY, May 1 (Xinhua) -- Increasing vegetation in cities by 30 percent could have prevented more than 1.1 million heat-related deaths globally between 2000 and 2019, a Monash University study said on Thursday.
The 20-year modelling study assessed the health impact of urban greening in over 11,000 cities across the globe. Regions with the most significant gains included Southern Asia, Eastern Europe, and Eastern Asia, where heat-related mortality is highest, according to a news release by Australia's Monash University on Thursday.
The research found that adding 10 percent, 20 percent and 30 percent more vegetation in urban areas would reduce warm-season temperatures by 0.08, 0.14, and 0.19 degree respectively, potentially averting 0.86 million, 1.02 million, and 1.16 million deaths, or up to 36.7 percent of all heat-related fatalities over the study period.
The study, published in The Lancet Planetary Health, used data from 830 locations in 53 countries and regions, with greenness measured via the United States' National Aeronautics and Space Administration's Enhanced Vegetation Index, derived from satellite imagery.
Urban greenery cools cities through shading, evapotranspiration and radiation deflection, helping to reduce heat exposure. Beyond cooling, vegetation may also offer indirect health benefits by improving air quality, mental health, and physical activity levels, said Guo Yuming, professor of Monash University and leader of the study.
"These findings indicate that preserving and expanding greenness might be potential strategies to lower temperature and mitigate the health impacts of heat exposure," Guo said.
Heat currently causes around 0.5 million deaths annually and is projected to account for up to 16.7 percent of total mortality in Southeast Asia by the end of the century if global warming continues unchecked, he said. ■
