Climate Modeling (Meteo 523): Project Two

Climate Modeling (Meteo 523)
Project Two: Validation of Climate General Circulation Models

Assertion:If global climate models (GCM) can be demonstrated to simulate the present climate accurately, we can have increased faith in their ability to simulate other climate regimes through sensitivity studies.
Corrollary:If GCM do not accurately simulate the present climate, our faith in their validity when simulating other climate regimes is diminished.
The skill of Climate GCMs is assessed by comparison of simulations of the present climate with observations. This process of validation of the model in the present climate (hopefully) extends further than simple measures such as the global averaged surface temperature to include the model atmosphere's spatial structure (locations of key atmospheric features such as the Asian monsoon and the midlatitude storm track), and its range of temporal variability (diurnal, intra-annual, interannual and possibly interdecadal). For coupled models, similar studies of the ocean, cryosphere and biosphere would ideally be undertaken, although the period of record of observational data for validation (at least for the ocean and cryosphere) is problematic here. These validation studies are intended to impart confidence that the model is capable of simulating the key features of the present climate system.
The Atmospheric Model Intercomparison Project (AMIP) was set up to evaluate the skill of the suite of GCM available in 1990. Many papers resulted from this study, each concentrating on a specific aspect of the atmosphere. More on AMIP can be found here. AMIP II (covering the longer period 1 Jan 1979 - 1 March 1996) began in 1995. It is convened under the auspices of the Working Group on Numerical Experimentation (WGNE) of the World Climate Research Programme (WCRP).
Another coupled modeling study that,might be of more interest to this group is the Coupled Model Intercomparison Project (CMIP). Phase I of CMIP began in 1995 and encompasses studies of 18 GCM. CMIP is convened under the auspices of the Working Group on Coupled Models (WGCM) of CLIVAR.
Links to other model intercomparison projects, such as the Seasonal Prediction Model Intercomparison Project (SMIP), and the Paleoclimate Model Intercomparison Project (PMIP) can be found here.

Assessment
This project consists of a classroom presentation, leading one classroom discussion and an evaluation paper. All class members must read all papers to be used in the discussions.

Classroom presentation on a regional climate 6 April 1999
Model validation papers form the basis of six discussions (with each class member leading one of the discussions)
Write a summary paper based on your climate model discussion.

Project Assignments

Class Member Region Discussion Paper
Persa Amazon Sperber, K. R., and T.N. Palmer, 1996: Interannual tropical rainfall variability in general circulation model simulations associated with the Atmospheric Model Intercomparison Project. J. Climate, 9, 2727-2750.
Dave Canadian Northwest Territories Chen et al., 1995: Simulations of the 1979-1988 polar climates by global models. Annals of Glaciology, 21, 83-90.
Giang Antarctica Randal et al., 1992: Intercomparison and interpretation of surface energy fluxes in AGCM. J. Geophys. Res., 97, 3711-3724.
Phillip Siberia D'Andrea, et al., 1998: Northern Hemispheric atmospheric blocking as simulated by 15 atmospheric general circulation models in the period 1979-1988. Climate Dynamics, 14, 385-407.
Jeff Tibetan Plateau R. D. Cess et al., 1990: Intercomparison and interpretation of climate feedback processes in 19 atmospheric GCM's. J. Geophys. Res., 95, 16601-16615.
Manajit South Asia Barnett, T. P., 1999: Comparison of near-surface air temperature variability in 11 coupled global climate models. J. Climate, 12, 511-518.

Paper Focus
There are two obvious directions you could take your paper for this project. Either one is acceptable:
(1) Use this discussion paper as a springboard to recommend needed advances in climate models that would improve them and therefore increase confidence in the use of these models for sensitivity studies (climate change or palaeoclimate scenarios) and policy making; or

(2) Critique the model validation process, assessing the current procedures and potential new alternatives.
You should be certain that your paper is not too similar to Project 1. Hence, if your topic has the same focus, perhaps use alternative (2) for the paper to ensure that there is a clear distinction in my mind of the work you've done for each project.

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Last Updated: 9 April 1999

Class Member	Region	Discussion Paper
Persa	Amazon	Sperber, K. R., and T.N. Palmer, 1996: Interannual tropical rainfall variability in general circulation model simulations associated with the Atmospheric Model Intercomparison Project. J. Climate, 9, 2727-2750.
Dave	Canadian Northwest Territories	Chen et al., 1995: Simulations of the 1979-1988 polar climates by global models. Annals of Glaciology, 21, 83-90.
Giang	Antarctica	Randal et al., 1992: Intercomparison and interpretation of surface energy fluxes in AGCM. J. Geophys. Res., 97, 3711-3724.
Phillip	Siberia	D'Andrea, et al., 1998: Northern Hemispheric atmospheric blocking as simulated by 15 atmospheric general circulation models in the period 1979-1988. Climate Dynamics, 14, 385-407.
Jeff	Tibetan Plateau	R. D. Cess et al., 1990: Intercomparison and interpretation of climate feedback processes in 19 atmospheric GCM's. J. Geophys. Res., 95, 16601-16615.
Manajit	South Asia	Barnett, T. P., 1999: Comparison of near-surface air temperature variability in 11 coupled global climate models. J. Climate, 12, 511-518.