Introduction
General Circulation Models (GCMs) are routinely used to simulate and predict Earth’s past, present and future climate (e.g. IPCC, 2007). Although models broadly agree, significant differences exist in the detail of their predictions (e.g. Randall et al., 2007). Unfortunately, paleoclimate modeling studies often utilize only a single model, meaning the results obtained may be highly model-dependant. To combat this bias, the international Palaeoclimate Modelling Intercomparison Project (PMIP) was initiated to coordinate and encourage the systematic study of several GCMs and to assess their ability to simulate large changes in paleoclimate (e.g. Joussaume and Taylor, 1995). In 2007 PMIP coverage was extended beyond the Last Glacial Maximum and the mid-Holocene climatic optimum to the mid-Pliocene, a time period identified by the IPCC as a potential analogue for future climate change (Jansen et al., 2007).
The mid-Pliocene warm period has provided a focus for data synthesis and paleoclimate modeling for the last two decades (e.g. Chandler et al., 1994; Sloan et al., 1996; Dowsett et al., 1994, 1999; Haywood et al., 2000). Though numerous GCM simulations of the Pliocene have been conducted, rarely has any systematic attempt been made to conduct experiments in a fashion that would make direct comparisons possible, and our view of the mid-Pliocene world is still largely based on outputs from only a few GCMs.
Recently, a pilot intercomparison using the NASA GISS and Hadley Centre GCMs, using prescribed PRISM boundary conditions, has revealed a number of important differences in the model results, raising questions regarding both the Pliocene climate and the ability of GCMs to simulate warm climates. This pilot study serves as a springboard for the larger internationally coordinated Pliocene Paleoclimate Modeling Intercomparison Project (PlioMIP), a component of the new PMIP3 initiative. PlioMIP has multi-agency support in the U.S. and numerous participants from the international community . The project will help enable the systematic study of GCMs for a warm period in Earth history that roughly parallels climate predictions for the end of this century.
Haywood, A.M. et al. (2009). Global & Planetary Change.
IPCC, (2007). Climate Change 2007: The Physical Science Basis.
Jansen, E. et al. (2007). Palaeoclimate. In: Climate Change 2007: The Physical Science Basis.
Randall, D.A. et al. (2007). Climate Models and Their Evaluation. In: Climate Change 2007: The Physical Science Basis.
Haywood, A.M. et al. (2000). Geology 28, 1063-1066.
Dowsett, H.J. et al. (1999). USGS Open File Report 99-535.
Sloan, L.C. et al. (1996). Marine Micropaleontology 27, 51-61.
Joussaume, S. and K. E. Taylor, (1995). Proceedings of the first international AMIP scientific conference. WCRP Report, 425-430.
Chandler, M.A. et al. (1994). Global & Planetary Change 9, 197-219.
Dowsett, H.J.et al. (1994). Joint investigations of the middle Pliocene climate I: PRISM paleoenvironmental reconstructions. Global and Planetary Change 9: 169-195.
Background information information useful for PlioMIP research proposals. Supplied by Haywood and Lunt.
Planned Analyses
Send an e-mail describing your related research or ideas for related research. Information on your analysis will be posted here. Include:
- Title of analysis
- Leader
- A short description of the analysis (less than 100 words)
- Proposed start and completion dates
- A list of other interested participants
Input data for analysis are found here.
Results of PlioMIP research are found here.
Join a discussion of PRISM and PlioMIP topics on Google Groups or send the group a message.
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