LOS ANGELES, May 3 (Xinhua) -- Climate change might cause more heat waves which may in turn lead to more fatalities in U.S. cities in the coming decades, a new study has found.
For the study, researchers at the Johns Hopkins Bloomberg School of Public Health developed three climate change scenarios for 2081 to 2100, which were based on estimates from seven global climate change models and from mortality and air pollution data for the city of Chicago from 1987 to 2005.
The data were limited to the warm season from May to October of each year.
The researchers calculated that the city of Chicago could experience between 166 and 2,217 excess deaths per year attributable to heat waves using three different climate change scenarios for the final decades of the 21st century.
Global climate change is anticipated to bring more extreme weather phenomena such as heat waves that could impact human health in the coming decades, the researchers concluded in the study published in the May edition of the journal Environmental Health Perspectives.
"Our study looks to quantify the impact of increased heat waves on human mortality. For a major U.S. city like Chicago, the impact will likely be profound and potentially devastating," said Roger Peng, PhD, lead author of the study and associate professor in the Department of Biostatistics at the Bloomberg School of Public Health. "We would expect the impact to be less severe with mitigation efforts including lowering CO2 emissions."
From 1987 to 2005, Chicago experienced 14 heat waves lasting an average of 9.2 days, which resulted in an estimated 53 excess deaths per year, according to background information provided by the researchers.
The researchers calculated that in the future, excess mortality attributable to heat waves would range from 166 to 2,217 per year in the city.
The projections of excess deaths could not be explained by projected increases in city population alone, the researchers noted, adding that the exact change due to global warming in annual mortality projections, however, is sensitive to the choice of climate model used in analysis.
"It's very difficult to make predictions, but given what we know now -- absent any form of adaptation or mitigation -- our study shows that climate change will exacerbate the health impact of heat waves across a range of plausible future scenarios," added Peng.