The loss of huge ice masses can contribute to the warming that is causing this loss and further risks. A new study now quantifies this feedback by exploring long-term if-then scenarios. If the Arctic summer sea ice were to melt completely, a scenario that is likely to become reality at least temporarily within this century, this could eventually add roughly 0.2 degrees C to global warming. It is, however, not in addition to IPCC projections of future warming, since these already take the relevant mechanisms into account. Still, the scientists have now separated the effects of the ice loss from other effects and quantified it.