The water resource sector is one of those most likely to experience significant effects from climate change; however, water resource managers are unable to directly use the output from climate models to inform their planning. Such models do not adequately represent important hydroclimate phenomena; most notably, the effect of regional mountain ranges on precipitation and temperature is not resolved. As a result, water managers have turned to simplistic statistical downscaling methods, though these methods may not represent the physical processes any better than the global model. Even regional climate models (RCMs) have too great a computational cost at the spatial resolutions desired. Here we present a new modeling approach, the Intermediate Complexity Atmospheric Research model (ICAR) developed to represent processes important for water resources, particularly orographic effects. ICAR uses an analytical solution for flow over topography to adjust the large scale wind field; this is used to advect heat and moisture through the domain while calculating the same physical processes that a traditional RCM would (e.g. cloud microphysics and land surface feedbacks.) Because of its simplifying assumptions, ICAR is capable of running 100-1000 times faster than a traditional RCM, while still reproducing key facets of the regional climate. In addition, we can use ICAR to explore some of the, often ignored, uncertainties within regional and global climate modeling including the strength of the snow-albedo feedback effect and the variability in cloud microphysical parameters.
GFDL Formal Seminar
Thu, May 2, 2019, 2:00 pm to 3:00 pm
Smagorinsky Seminar Room 209