To Reduce Mortality From High Heat in Cities, a New Study Recommends Trees - Inside Climate News

2023-03-03

Excerpt from this story from Inside Climate News:

Nearly 40 percent of the thousands of deaths that can be attributed to high heat levels in cities could have been avoided through increased tree coverage, a recent study from Barcelona’s Institute of Global Health found.

Past studies have linked urban heat with increased mortality rate and hospital admissions for adults and children. This link between high temperature and mortality holds both in times of extreme and moderate heat. In addition to conducting a similar analysis between urban heat and mortality, the Institute of Global Health’s study went on to estimate possible reductions in temperature and mortality that may result from increased tree coverage.

To establish the reduction in heat-induced urban mortality from increased tree coverage, researchers first compared mortality rates in warmer urban areas with mortality rates in cooler non-urban areas. This allowed them to estimate the relationship between increased temperature and mortality in urban areas. Researchers were then able to estimate the degree to which planting more trees could decrease temperature and thereby urban mortality rates. Specifically, a 30 percent increase in tree coverage could lead to 40 percent fewer deaths from urban heat.

Mark Nieuwenhuijsen, a research professor at ISGlobal and the study’s senior author, said the strength of their paper is in its holistic analysis of the issue. By linking heat, mortality and urban greening, the paper is able to stand at the “nexus of the climate crisis, urban forestry, health and urban planning,” said Nieuwenhuijsen, who also directs ISGlobal’s urban planning, environment and health initiative.