The sensitivity of snowmelt processes to climate conditions and forest cover during rain‐on‐snow: a case study of the 1996 Pacific Northwest flood

Changes in Mechanisms and Characteristics of Western U.S. Floods Over the Last Sixty Years

“…Our classification corroborates results from previous studies, which show that ARs dominate flood events in the Pacific Northwest and coastal northern California, and that ROS is the dominant FGM throughout the Washington and Oregon Cascades (Barth et al., 2017; Konrad & Dettinger, 2017; Marks et al., 1998; McCabe et al., 2007; Ralph et al., 2006, 2011). For 70% of basins across our study domain, the dominant FGM accounts for more than 50% of all flood events (Figure S3b in the Supporting Information ).…”

The cold rain‐on‐snow event of June 2013 in the Canadian Rockies — characteristics and diagnosis

“…As a result, although snowmelt energy to existing snowpacks declined during the ROS as a result of the reduction in net shortwave radiation exceeding the net increases in advected heat, longwave radiation and the turbulent heat fluxes, the areally averaged snowmelt energy to the basin increased as a result of the increase in snow‐covered area and ground heat fluxes from newly snow‐covered warm ground into the snowpack. This differs substantially from the classic mid‐winter ROS of substantially increased sensible and latent heat fluxes along with advected energy driving more rapid snowmelt described by Marks et al (, ) and Mazurkiewicz et al (). So, although snowmelt rates of existing snowpacks dropped by one third during the flood, snowmelt from the basin increased by almost one half, and snowmelt formed an appreciable (>1/5th) contribution to water inputs to the alpine basin during the flood.…”

Distributed energy balance modeling of South Cascade Glacier, Washington and assessment of model uncertainty

“…Insolation is low, yet single time step energy flux totals achieve values ∼30% higher than during the subsequent clear, calm period. The magnitude of these heat fluxes is comparable to that modeled by Marks et al [1998] and demonstrates that high ablation rates during warm, rainy periods are accounted for by turbulent heat fluxes rather than conductive heat flux from precipitation. Overall, conditions during the clear period show low turbulent heat fluxes due to strongly stable stratification, negative longwave balance, and dominance of the solar radiation flux.…”