Downscaled and Smoothed Surface Fluxes for GCM / Ice Model Coupling

Many questions still surround how ice sheets respond to climate forcing and what the magnitude of the impact will be on sea level. At present, state-of-the-art climate models can predict changes in ice-sheet surface mass balance. But the ice-sheet representations used in most climate models are not equipped to simulate rapid changes in ice dynamics and associated changes in mass. Developments to rectify this deficiency have become a high priority for both the climate and ice-sheet modeling communities. We present a series of surface mass and energy flux fields created by the GISS GCM for consumption by the ice model. We use a variety of techniques to generate these fields, including elevation classes in the GCM, temperature downscaling and QP regridding/smoothing. We focus on specific issues that arise in the GCM/ice coupling problem --- for example, artifacts introduced with temperature downscaling and discontinuities in runoff. Finally, we demonstrate how these techniques work together to create physically plausible surface mass and energy fluxes within the constraints of the GCM.