Science Source

Future risk of record-breaking summer temperatures and its mitigation

Projects the increased probability that summer temperatures in the future will exceed the hottest on record during 1920–2014 at all land locations with global warming
Investigates the sensitivity of this projected change in probability to the choice of emissions scenario using two large ensembles of simulations with the Community Earth System Model, within the BRACE project framework
States that the large ensemble size allows for a robust assessment of the probability of record-breaking temperatures
Finds that the global probability that any summer during the period 2061–2081 will be warmer than the hottest on record is 80 % for RCP 8.5 and 41 % for RCP 4.5
Results indicate that mitigation can reduce the risk of record-breaking temperatures by 39 %
States the potential for risk reduction is greatest for some of the most populated regions of the globe—in Europe, for example, a potential risk reduction of over 50 % is projected
States that model biases and future changes in temperature variance have only minor effects on the results, as their contribution stays well below 10 % for almost all locations