If they are correct, the transition will occur by 2020 in Manokwari, Indonesia; by 2023 in Kingston, Jamaica; by 2029 in Lagos, Nigeria; by 2047 in Washington; by 2066 in Reykjavik, Iceland; and by 2071 in Anchorage.
“The boundary of passing from the climate of the past to the climate of the future really happens surprisingly soon,” said Christopher Field, director of the Department of Global Ecology at the Carnegie Institution for Science. Field was not part of the research team but has read the study, published in the journal Nature.
Researchers said at a news briefing that their estimates are “conservative,” based on mountains of data from 39 models and accurate within five years in either direction for any of the locations they studied.
Although scientific research shows that more warming occurs nearer to Earth’s poles — and the melting of arctic ice sheets is the iconic image of a warming planet — the tropics are especially vulnerable because even a small change in climate will affect a wide range of species. It is also alarming because the area around the equator is home to billions of people in poor nations with fewer resources to help them cope.
The study is hardly the first to document the steady march toward hotter temperatures around the globe. Less than two weeks ago, the Intergovernmental Panel on Climate Change (IPCC) released its fifth report, describing a planet that is warming at an accelerated pace because of human activity. The past three decades have been the hottest since 1850, according to the panel established by the United Nations, which added that warming and sea-level rise will continue through the 21st century.
But by predicting the tipping point when traditional climates will be replaced by hotter futures, the new study’s group — led by Camilo Mora, an assistant professor in the University of Hawaii at Manoa geography department — provided a fresh way to look at a problem that often is seen as a global phenomenon, except by authorities who must respond to the increasing toll of floods, droughts, wildfires and severe weather, experts said.
“I think people don’t appreciate the fact that one of the metrics we are most familiar with, and definitely have the most difficulty dealing with, extreme heat, is coming down the track,” said Michael Oppenheimer, a professor of geosciences at Princeton University.