NMME and the Frontier of Climate Scale Decision Support in Alaska

The advent of the near real-time North American Multi-Model Ensemble (NMME) project has opened up significant impact based decision support opportunities for the National Weather Service Alaska Region. Several high impact sectors are sensitive to climate scale variation at sub-seasonal time scales, and the higher temporal resolution combined with multi-model approach of the NMME allows, for the first time, a measurable of confidence in outlooks provided to federal and state partners working in these areas. The severity of spring river ice break-up ice jam flooding on Alaska's major rivers is strongly controlled by temperatures during April and May. The duration and overall severity of wildfire season are, unlike the inter-mountain West, not well correlated with preceding winter precipitation but by late spring and early summer temperature and both convective and stratiform precipitation. Previously available guidance was too coarse to allow for strategic planning of resources associated with these hazards. Future work using multi-model ensembles has the potential to provide one source of long lead outlooks for autumn Bering Sea storminess, which is historically the most economically costly weather event in Alaska and seasonal scale, regionally tailored sea ice outlooks, which is an emerging need by many partners, ranging from shipping to tourism to national security in a rapidly changing Arctic.