Atmospheric CO2 during the Early cenozoic from (mainly) boron isotopes (from Anagnostou et al. 2016 & Gutjahr et al. 2017). Also shown (bottom panel) is benthic oxygen isotopic composition - a proxy for climate (high values = cold, low values = warm).  The intervals Sweet will focus on are shown in grey.  Nacholite based CO2 in green (from Jagneicki et al. 2015)

Atmospheric CO2 during the Early cenozoic from (mainly) boron isotopes (from Anagnostou et al. 2016 & Gutjahr et al. 2017). Also shown (bottom panel) is benthic oxygen isotopic composition - a proxy for climate (high values = cold, low values = warm).  The intervals Sweet will focus on are shown in grey.  Nacholite based CO2 in green (from Jagneicki et al. 2015)

About

 In order to assess our confidence in predictions from climate models they need to be tested. However, our state-of-the-art climate models have never been tested under the high CO2, super-warm climate conditions to which they are primarily applied, and upon which major policy decisions are made. Luckily there exist time periods in Earth’s deeper past (for example the Eocene, about 50 million years ago) when CO2 concentrations were similar to those expected by the end of this century; but climatological information from these time periods is currently sparse and is associated with large uncertainties, and the exact concentrations of CO2 are only poorly known. In SWEET we will apply new and emerging techniques, and develop new methodologies and tools, to produce a global dataset of Eocene temperatures. Coupled with new and high-fidelity reconstructions of Eocene CO2 concentrations, and state-of-the-art maps of the ‘palaeogeograpy’ (continental positions, mountain ranges, ocean depths etc.), we will use this dataset to test a state-of-the art climate model under high atmospheric CO2, Eocene conditions.

SWEET has strong links to UK Met Office, and to the international DeepMIP project, which is part of the ‘Palaeoclimate Modelling Intercomparison Project’, itself part of CMIP6. To find out more please visit these DeepMIP and SWEET pages