Climate change, in response to increasing levels of greenhouse gases, has become a major societal and political issue. Potential changes in the mean and variability of climate over Canada, particularly changes in the frequency and occurrence of extreme weather events, may lead to substantial impacts on society, ecosystems and the economy. Governments, businesses and impact and adaptation planners all require detailed and reliable information on potential future climate change to support their long-term planning. The majority of planning agencies and government bodies require high-resolution climate information, at the regional or local scale, this being the scale at which they operate. Furthermore, information on the possible spread of future regional climate change and the probability of occurrence of individual projections is needed so clients can make a suitable risk-assessment of their planned operations factoring in appropriate information on the probable range of regional climate change. The need for a risk-based assessment of future climate change is particularly important with respect to changes in extreme weather and climate conditions that impact heavily on society and natural ecosystems.
The most efficient method to generate detailed information on regional climate change, at the spatial and temporal scales required, is through the use of a Regional Climate Model (RCM) dynamically embedded within a Global Climate Model (GCM). The GCM is run with a range of possible greenhouse gas emission scenarios and provides large-scale atmospheric and oceanic surface boundary conditions to a high-resolution RCM which provides a detailed estimate of the regional climate change, consistent with the evolving large-scale climate simulated by the GCM.
The Canadian Regional Climate Modelling and Diagnostics Network (CRCMD) will build on the achievements of past CRCM Networks to further improve the tools available to Canadian researchers and planners in the field of regional climate modelling and climate change assessment. This will be achieved by combining the main Canadian academic and government centres engaged in climate modelling and diagnostics into a single Network; the CRCMD Network. This Network will lead future development, application and evaluation of regional climate models within Canada.
The CRCMD Network has four primary aims. The first is to further
develop the new Canadian RCM (CRCM5) for optimum performance at
high-resolution (~10-20km). This will occur through the targeted
improvement of key parameterisation schemes. This work will utilise new
observations along with detailed, explicit models to improve the
performance of existing parameterisation schemes or, where necessary,
develop new parametric approaches targeted for high-resolution.
Parallel to this, an analysis of the scalability of present parametric
approaches from GCM to RCM resolutions will be made. This will indicate
the best approach for the combined development of GCMs and RCMs needed
for generating improved high-resolution, regional climate projections.
The second focus of the Network is to increase the physical realism of
surface-atmosphere interactions in CRCM5, with emphasis on regionally
specific processes over Canada. In doing this we aim to include more of
the local feedbacks that might alter an initial climate change over
Canada. To achieve this, the Network will incorporate interactive
modules for vegetation, lakes and regional oceans into CRCM5 and
evaluate the schemes at appropriate spatial and temporal scales. The
third focus is on improving diagnostic techniques used to analyse the
increasingly large amount of regional climate information available
today and in the near-future. These improvements will be aimed
specifically at high-resolution RCMs and extreme event analysis.
Furthermore, techniques will be developed to better evaluate and
communicate the uncertainty inherent in generating an ensemble of
regional climate change projections. The final focus of the Network,
cutting across all three science themes, is to continue the training of
Highly Qualified Personnel (HQPs) in the field of regional climate
modelling and diagnostics. This is a crucial requirement to maintain a
high-level of competence in this discipline within Canada and fulfill
an increasing demand for modelling expertise within the impact and