Turbulent fluxes during blowing snow: field tests of model sublimation predictions

Sublimation fluxes during blowing snow have been estimated to return 10-50% of seasonal snowfall to the atmosphere in North American prairie and arcti c environments. These fluxes are calculated as part of blowing snow two-pha se particle transport models with provision for phase change based upon a p article-scale energy balance. Blowing snow models have normally been evalua ted based upon their ability to reproduce diagnostic mass flux gradient mea surements and regional-scale snow redistribution patterns and snow mass. Di rect evidence is presented here that large latent heat fluxes (40-60 W m(-2 )) that result in sublimation rates of 0.05-0.075 mm snow water equivalent hour(-1), are associated with mid-winter, high-latitude blowing snow events . For events with wind speeds above the threshold level for snow transport, these fluxes are in the range of those predicted by the Prairie Blowing Sn ow Model. The fluxes are well in excess of those found during spring snowme lt and which can be predicted by standard bulk aerodynamic transfer equatio ns, suggesting that blowing snow physics will have to be incorporated in la nd surface schemes and hydrological models in order to properly represent s now surface mass and energy exchange during blowing snow events. Copyright (C) 1999 John Wiley & Sons, Ltd.