By 2080, many urban areas in the United States could have a climate similar to today's cities hundreds of kilometers to the south and southwest, according to a new study conducted in Nature Communications.
Why it's important: The projected climate changes if greenhouse gas emissions are not mitigated show that the climate with which young people are growing today will be radically different as soon as it will be older – and could even be unhealthy. to have "no modern equivalent".
- In the uncontrolled emission scenarios, the 540 cities all showed an increase in average annual temperature between the current city and its contemporary analogue, with an average increase of 8.2 ° F.
- Annual rainfall was more mixed, with 218 cities recording less rain and 322 with more, with an average variation of + 3 mm.
- On average, the contemporary analog city was 528 miles from its partner 2080.
- With lower emissions, the average distance decreases to 230 miles, average annual temperatures increase by 4.6 ° F and precipitation increases by 22 mm.
How they did it: The study, led by Matt Fitzpatrick at the Environmental Science Center of the University of Maryland, used 12 temperature and precipitation variables to create 27 climate projections for each city.
- The projections are based on two underlying emission scenarios, which have been combined with terrestrial system models to generate 54 future climate scenarios.
- One of the emission scenarios involves a reduction in global greenhouse gas emissions, but not enough to reach the temperature target of the Paris Agreement.
- The other scenario, presented on the map, implies that emissions continue to increase without control.
The researchers took the average projections of the 2080s for the 540 cities surveyed and compared it to the contemporary city with the most similar climate.