Billions of people could be living in regions where temperatures are hotter than their historical ranges by mid-century, creating a “new normal” that would impose profound changes on nature and society, scientists said on Wednesday.
Temperatures in an typical location in an average year would be hotter by 2047, than those in the warmest year from 1860-2005 if greenhouse gas emissions continue to rise, with the tropics the first affected area, a new index indicated. Eventually, the coldest year in a particular city or region will be hotter than the hottest year in its past.
"The results shocked us. Regardless of the scenario, changes will be coming soon," lead author Camilo Mora of the University of Hawaii said. "Within my generation whatever climate we were used to will be a thing of the past."
The data, published in the journal Nature, suggested the cities to be hit earliest included Manokwari in Indonesia, which could shift to a new climate from 2020. The earliest U.S. cities to hit that threshold would be Honolulu in 2043 and Orlando in 2046.
Photo: Provided by the authors of “The projected timing of climate departure from recent variability”