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The importance of the Pliocene and PlioMIP. Prof. Alan M. Haywood. School of Earth and Environment, University of Leeds, UK Thanks to Harry Dowsett and the PRISM Team and the PlioMIP Advisory Group plus many more…. Inspiration. To slight irritation....
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The importance of the Pliocene and PlioMIP Prof. Alan M. Haywood School of Earth and Environment, University of Leeds, UK Thanks to Harry Dowsett and the PRISM Team and the PlioMIP Advisory Group plus many more…
To slight irritation.... • CO2 change moderate compared to 21st century estimates • Represents a long term steady-state not a transient style forcing • Solution: PETM ideal analogue perturbation • ?
Analogue Issues Haywood et al. (2011). Phil Trans R. Soc. A.
Analogue Issues MODERN: Annual mean Precip. minus Evap. 2 × minus 1× PAL CO2 EOCENE: annual mean Precip. minus Evap. 2 × minus 1× PAL CO2 Haywood et al. (2011). Phil Trans R. Soc. A.
So why the Pliocene? • We have abundant geological data for the Pliocene • Pliocene CO2 concentrations were almost the same as today • Continents were in their modern positions • Pliocene ecosystems were similar to modern
Again... why the Pliocene? Climate Sensitivity Earth System Sensitivity Lunt et al. (2010). Nature Geoscience “The panellists were convinced of the utility of the Pliocene as a means to distinguish short and longer term climate/earth system sensitivity and associated ramifications for identifying a CO2 threshold that should not be crossed to avoid dangerous climate change”.
Policy relevant tipping elements Lenton et al. (2008).
Mechanisms, Forcings and Feedbacks... Annual mean temperature change (Pliocene minus Pre-Ind)
Mechanisms, Forcings and Feedbacks... CO2 Orog. Veg. Ice
Ocean Circulation and Heat Transport Ravelo et al. (2007)
Climate Variability/Oscillations Mg/Ca SSTs 0 3 5 Age (Ma) Wara et al. (2005)
High Latitude Climate/Polar Amplification Ballantyne et al. (2011)
Our job at this workshop... Generate ideas Prioritise those ideas Deliver those ideas...