Enhanced Arctic warming amplification revealed in a low-emission scenario

The Arctic region has warmed faster than the global mean in past decades. Future climate change projections also suggest this Arctic warming amplification will continue. Here, using 50-member historical and future scenario simulations by a single climate model, we find that Arctic warming amplification is stronger in a low-emission scenario, compared to a high-emission scenario, after the mid-2040s. This is because in the low-emission scenario, sea ice continues to exist beyond 2040 and the ice-albedo feedback therefore maintains Arctic warming, unlike other latitudes. By contrast, in the high-emission scenario summer sea ice melts away by about 2050. Multi-model analyses show that the strength of Arctic amplification in the low-emission scenario is highly correlated with the amount of sea-ice reduction, whereas this relationship weakens in the high-emission scenario. Our results indicate that climate change mitigation may have a side effect because Arctic warming persists even if the global warming is stabilized. Arctic warming amplification is intensified in a low-emission scenario after the mid-2040s, compared to a high-emission scenario, because of a continuing ice-albedo feedback, according to 50-member ensemble simulations with a climate model.

Automated summary

Research indicates that Arctic warming amplification is expected to be stronger in a low-emission scenario compared to a high-emission scenario. In the high-emission scenario, summer sea ice may completely melt away by around 2050, while in the low-emission scenario, the reduction of sea ice contributes to Arctic warming amplification.