Winter snow conditions on Arctic sea ice north of Svalbard during the Norwegian young sea ICE (N‐ICE2015) expedition

Abstract

Snow is a crucial component of the Arctic sea ice system. Its thickness and thermal properties control heat conduction and radiative fluxes across the ocean, ice, and atmosphere interfaces. Hence, observations of the evolution of snow depth, density, thermal conductivity, and stratigraphy are crucial for the development of detailed snow numerical models predicting energy transfer through the snow pack. Snow depth is also a major uncertainty in predicting ice thickness using remote sensing algorithms. Here we examine the winter spatial and temporal evolution of snow physical properties on first‐year (FYI) and second‐year ice (SYI) in the Atlantic sector of the Arctic Ocean, during the Norwegian young sea ICE (N‐ICE2015) expedition (January to March 2015). During N‐ICE2015, the snow pack consisted of faceted grains (47%), depth hoar (28%), and wind slab (13%), indicating very different snow stratigraphy compared to what was observed in the Pacific sector of the Arctic Ocean during the SHEBA campaign (1997–1998). Average snow bulk density was 345 kg m−3 and it varied with ice type. Snow depth was 41 ± 19 cm in January and 56 ± 17 cm in February, which is significantly greater than earlier suggestions for this region. The snow water equivalent was 14.5 ± 5.3 cm over first‐year ice and 19 ± 5.4 cm over second‐year ice.

Winter to summer oceanographic observations in the Arctic Ocean north of Svalbard

“…Snow‐free and thinner sea ice would allow for further growth in particular during cold winters, despite the relatively large ocean heat flux in the region [ Peterson et al ., , ; Meyer et al , ]. Snow cover was however thick during N‐ICE2015 [ Merkouriadi et al , ; Rösel et al ., ] insulating the ice from the atmosphere and preventing sea ice growth (A. Rösel, personal communication, September 2016). It is instead in the many observed leads that strong thin ice growth was observed.…”

Thin Sea Ice, Thick Snow, and Widespread Negative Freeboard Observed During N‐ICE2015 North of Svalbard

“…In the context of sea‐ice and snow observations as well as heat fluxes during N‐ICE2015, some relevant studies have been already published: Merkouriadi et al () and Gallet et al () describe snow pack properties and it's transition from winter to summer. They describe a unique snow stratigraphy with a distinct depth hoar layer in the bottom that impacts the thermal conductivity of the snow.…”

The NASA Eulerian Snow on Sea Ice Model (NESOSIM): Initial model development and analysis

“…Snow depth and density information collected during the Norwegian young sea ICE (N-ICE2015) expedition (Merkouriadi et a., 2017) Geosci. Model Dev.…”