For decades, global climate models (GCMs) have produced equilibrium climate sensitivities (ECSs) between 2 and 4.5°C, but interestingly that is now about to change: a subset of state-of-the-art GCMs participating in the 6th coupled model intercomparison project is producing ECSs well above 5°C. Here, analyses based on one such high-ECS model will be presented. In the past, it has been assumed that such very high simulated ECSs would make it practically impossible for GCMs to reproduce the historical temperature record, but that turns out not to be the case. This is because the model in question has a net positive cloud-climate feedback that grows with warming – in other words: the warmer it gets, the more clouds change in a way that further amplifies the warming, while for modest warming the amplification is much smaller. In this presentation Trude Storelvmo will explain the underlying physical mechanism responsible for the simulated state transition and discuss its general validity and broader implications.
Veranstalter: | Max-Planck-Institut für Meteorologie (MPI-M) |
Veranstaltungsort: | Raum 022/023 Bundesstrasse 53 20146, Hamburg |
Beginn: | 05.12.2019 15:15 Uhr |
Ende: | 05.12.2019 17:00 Uhr |
Internet: | Weitere Informationen |