Project Title: Comparison of GCM predictions for 2099
Eleven GCM (Global Circulation Models) are provided in in climate models Each models predicts different climate varaibles like
Surface temperarure, Atmospheric temperature,
Snow Cover etc.
AR5 provides an excellent platform for viewing the results of all these eleven models on world map. It helps common people to understand the degree and extent of climatic changes looming over earth. Different models adopt different types of couplings of submodels or follow slightly different methodologies. Exhaustive comparison of eleven model results for all variables for year 2000 as well as future predictions (say 2099) are beyond the scope of this work. However two observations are provided in following paragraphs as examples of variation in prediction results:
1. CNRM-CM5 simulates that Green land as a cooler zone ( temperature is less by -10deg over vast area, close to -40 deg C ) for year 2000 as well as 2099 in comparison to other standard models like CCSM4 (Figur1a & b).
2. CSIRO-Mk3-6 predicts the hotter climate for south America, Africa and India in 2099.
These GCMs are usually named on basis of the source institutes. The reasons for the above mentioned differences in predictions are a briefly discussed in the following section.
1. bcc-csm1-1 (Beijing Climate Centre Climate System Model)
2. BNU-ESM ((Beijing Normal University-ESM))
(Canadian Earth System Model) .
4. CCSM4 (The Community Climate System Model (CCSM) is a coupled Global Climate Model developed by the University Corporation for Atmospheric Research (UCAR) with funding from the National Science Foundation, Department of Energy, and NASA. This model is used as a standard tool.
(NRM-CM5) is an Earth system model.
Greenland is simulated to be more cooler in 2000 as well as 2009. This may be due to a very strong cold bias imbibed in the model. This ‘‘blue spot’’ of north Atlantic is a known problem that is amplified in the new NEMO configuration.(Figure 1b) (Reference: 1)
6. CSIRO-Mk3-6-0 predicts south America, Africa India to be hotter by +10 deg C in future.
In almost all models historical climate forcing is used, which is a reconstruction of both the anthropogenic and the natural climate forcing. For the future, the RCP8.5 scenario is taking to represent "business as usual" and are compared for RCP 2.6. However, CSIRO uses RCP 4.5 and thus differs in prediction from other models (Reference 2).
7. GISS-E2-H (Goddard Institute for Space Studies)
IPSL-CM5A-LR The Institute Pierre
Simon Laplace (IPSL)
is a governmental funded research centre devoted to research in the climate
system and global environment.
MIROC-ESM”, is based on a global climate model MIROC (Model for Interdisciplinary Research on Climate) which has been cooperatively developed by he University of Tokyo, NIES, and JAMSTEC
10. MRI-CGCM3 (Meterological Reserch Institute /JMA)
11. NorESM1-M Surf Temp Annual Mean, 2099
The Norwegian Climate
Center's Earth System Model, named NorESM1-M, is presented.
Al though all models show warming trend but the results of every model should reviewed and compared before accepting it as a final result.
Reference 1:http://www.cnrm.meteo.fr/cmip5/IMG/pdf/Voldoire_et_al_CD_online.pdf (page 12 of 31)