Manhattan may see deaths from heat rise by as much as 20 percent in the 2020s and 90 percent by the 2080s in a worst-case scenario, a study found.
The study, published this week in the journal Nature Climate Change, was done by Columbia University’s Earth Institute and the Mailman School of Public Health. Higher winter temperatures may cut cold-related mortality, though net temperature-related deaths may still climb by a third by the 2080s, according to a statement detailing the findings.
“This serves as reminder that heat events are one of the greatest hazards faced by urban populations around the globe,” said Radley Horton, a climate scientist at the Earth Institute’s Center for Climate Systems Research and a co-author.
Governor Andrew Cuomo has said New York must prepare for a “new reality” of climate change after Hurricane Sandy, the largest Atlantic storm in history, smashed into New York City Oct. 29. It caused the worst flooding in the more than 100-year history of the subway system and about $40 billion in damage statewide. The 55-year-old Democrat has included climate change as a risk to bond investors in offering statements.
Horton said there’s already evidence of deaths caused by rising temperatures. In 2010, a heat wave in Russia killed about 55,000, he said. A similar event in Central and Western Europe killed 70,000 in 2003.
The study used temperature projections from 16 global climate models and put them against two backdrops, according to the statement. One backdrop assumed rapid population growth and few attempts to limit greenhouse-gas emissions. The other assumed slower population growth and technological changes that reduced emissions by 2040.
It used as a baseline the 1980s, when an estimated 370 Manhattan residents died annually from overheating and 340 were killed by cold weather. The worst-case scenario translates to more than 1,000 annual temperature-related deaths by the 2080s, the study found.
Daily records from Central Park in New York show that average monthly temperatures increased 3.6 degrees Fahrenheit from 1901 to 2000, the statement said. Last year was the warmest on record in Manhattan, it said. In cities, heat is concentrated by buildings and pavement. The temperature in New York is expected to climb by as much as 4.2 degrees Fahrenheit by the 2050s, the statement said.
The study found that the largest percentage increase of deaths in Manhattan will come during May and September rather than the traditionally hottest months of June through August.
Heat-related mortalities would be offset by a 12 percent drop in deaths due to cold in the 2020s, the statement said. That means a net increase of 5 percent or 6 percent in temperature-related deaths for that decade. By the 2080s, the best-case scenario is a net 15 percent rise, the worst about 30 percent, it said.
“This points to the need for cities to look for ways to make themselves and their people more resilient to heat,” said Patrick Kinney, an environmental scientist at the Mailman School and the study’s senior author.