Climate change is raising temperatures, but the impact could be worse in the world’s cities. Researchers say the urban heat island effect – or the fact that cities are hotter thanks to human activity – combined with climate change could increase temperatures in urban areas by around 14.4 degrees Fahrenheit, or eight degrees Celsius, by the end of the 21st century.
Three researchers led by Francisco Estrada of the Universidad Nacional Autónoma de México and the Institute of Environmental Studies projected city temperatures could rise by around five degrees Celsius due to climate change, as well as an additional two or three degrees Celsius as asphalt and concrete crowd out parks and lakes in metropolises, inducing the urban heat island effect. Such increased temperatures could impact human health and burden natural resources.
As major cities prepare for the impacts of climate change, many of them likely haven’t been considering the urban heat island effect. The researchers said many impact estimates don’t include the effect. So they drew on average planetary warming projections combined with the effect, and used data from 1,692 of Earth’s biggest cities between 1950 and 2015, to determine the economic costs of climate change. They also built their research on worse case scenarios: if carbon emissions continue to rise instead of declining. The results aren’t pretty: cities hit the hardest could lose 10.9 percent of GDP by 2100.
Only around one percent of the planet’s surface is covered with cities, but the urban centers produce around 80 percent of gross world product. Around 78 percent of the energy consumed worldwide happens in cities. They also generate over 60 percent of global carbon emissions from burning fossil fuels.
The journal Nature Climate Change published the research online this week.
Via The Guardian