Because of the uncertainties surrounding prediction of climate change, it is common to employ climate scenarios to estimate its imapcts ona system. Climate scenarios are setsof climatic perturbations used with models to test system sensitivity to projected changes. In the study, four general circulation model (GCM) predictions are overlaid and the composite used to derive climate change scenarios that will be used in the future in rice models to estimate potential future change in yield and other agronomically important variables. This approach provides a means to identify model uncertainties and provides error bars for the projections. A review of current climatic conditions in Thailand provides a simple test of the predictions validity. Temperature changes are important for rice culture which provides food and economic stability to the country. Increased precipitation could mean greater flooding problems in the plains.