01.07.2016: SFB754 Kolloquium

08:45 Uhr, Gr. Konferenzraum GEOMAR, Düsternbrooker Weg 20

Abstract:

Global mean surface temperatures are rising in response to anthropogenic greenhouse gas emissions. The magnitude of this warming at equilibrium for a given radiative forcing – referred to as specific equilibrium climate sensitivity (S) – is still subject to uncertainties. Here we estimate global mean temperature variations and S using a 784,000-year-long field reconstruction of Sea Surface Temperatures and a transient paleo-climate model simulation. Our results reveal that S is strongly dependent on the climate background state with significantly larger values attained during warm phases. Using the Representative Concentration Pathway 8.5 for future greenhouse radiative forcing, we find that the range of paleo-based estimates of earth’s future warming by year 2100 overlaps with the upper range of climate simulations published in the current IPCC. Furthermore, we find that it is very likely that within the 21^st century global mean temperatures will exceed maximum levels reconstructed for the last 784,000 years.

Kontakt:
Andreas Oschlies