Theme Leaders: Caya, de Elía and Laprise
Since the first reported regional climate modelling work in the late 1980s, it has been common to find at most a few regional climate projections for any given area of the world. Over recent years structured international programmes have enabled the generation of ensembles of simulations involving multiple global and regional models, following various emission scenarios. In addition to the increased number of simulations, the resolution of RCMs has evolved from values typically around 50km towards values closer to 20km. One such international project, the North American Climate Change Assessment Program (NARCCAP) makes use of 6 RCMs and 4 driving GCMs to generate an ensemble of simulations for current and future climates over a domain encompassing all of North America.
The NARCCAP bank of simulations in addition to the one generated by the Ouranos' Climate Simulations Team will provide an unprecedented availability of regional-climate information to the CRCMD Network. These two banks will have simulations resulting from various combinations of CGCMs (CGCM2, CGCM3, HadCM3, NCAR-CCSM and GFDL), AGCMs (ARPEGE and HadAM3) and RCMs (CRCM3, CRCM4, CRCM5, HadRCM3, RegCM, NCEP-RSM, MM5 and WRF, see appendix A for a list of model acronyms). As a consequence, diagnostic studies can be more thoroughly conducted and a more precise evaluation of the uncertainty associated with regional-climate projections can be addressed. A thorough evaluation of the uncertainty inherent in climate projections is important, since most impact and adaptation studies require such an evaluation in order to define an appropriate range of adaptive solutions.
One of the main objectives of this theme is to develop new approaches to take advantage of this newly available database. The amount of information available is both exciting and challenging; exciting because never before has such an amount of data been available to study the North American climate, and challenging because new approaches must be developed to handle such a large quantity of data (hundreds of Terabytes) and extract and disseminate useful information from it.
The majority of the diagnostic work in this theme will be dedicated to assessing this suite of regional climate simulations over North America. One diagnostic project will go a step further and evaluate the new CRCM5 as a regional modelling tool for other regions and climatic regimes on the globe. This effort will indicate the universal applicability of the system as a high-resolution downscaling tool, indicating its potential to generate regional climate-change projections in other regions of the world.