The Influence of Melting Snow in the Ocean Surface Heat Budget

Abstract:

Over half of all snow that falls in the planet falls in the ocean. However, the cooling that occurs when snow melts into the ocean is often left out of weather and climate simulations, even though the cooling effect of melting ice in the atmosphere is calculated during near-identical cold rain storms. In order to determine whether there may be consequences in omitting this ocean snowfall cooling effect, we use satellite observations and reanalysis to estimate the influence of melting snow on the net ocean surface heat flux on instantaneous and seasonal time scales. During snow storms, we find that the cooling of melting snow may often be more powerful than all other heat fluxes (compared to radiation, evaporation, and sensible heat transfer). During SON and MAM when the average heat flux of the ocean is close to thermodynamic equilibrium, the 0-10 W/m^2 average cooling flux from snow can average up to 10% of the ocean surface heat flux, especially in ocean regions close to sea-ice formation zones. These results demonstrate that the cooling influence of melting snow is a considerable force, and it is reasonable to suspect that it could be influencing various oceanic, atmospheric, and/or cryospheric phenomena. We plan to demonstrate and quantify the influences in future research.