IAOOS winter SIMBA data during N-ICE 2015 North of Svalbard
|Temporal extent||2015-01-24 -2015-03-16|
|Author(s)||Sennéchael Nathalie1, Provost Christine1, Villacieros-Robineau Nicolas1, Calzas Michel2, Guillot Antoine2, Savy Jean-Philippe3, Garracio Magali4, Koenig Zoé1|
|Affiliation(s)||1 : Laboratoire LOCEAN-IPSL Sorbonne Université (UPMC, Univ. Paris 6)-CNRS-IRD-MNHN, Paris, France
2 : Division Technique de l'INSU/CNRS, Brest, France
3 : Laboratoire d'Etudes en Géophysique et d'Océanographie Spatiales (LEGOS), Toulouse, France
4 : Institut Polaire Francais Paul-Emile Victor (IPEV)
|Keyword(s)||sea ice, snow, ice growth, basal melt, flooding, snow-ice, mass balance|
Two ice mass balance instruments (part of IAOOS7 and IAOOS8 platforms) deployed near 83°N on the same ice floe, documented the evolution of snow and ice conditions in the Arctic Ocean north of Svalbard in Jan-Mar 2015. Frequent profiles of temperature (every 3 hours) and temperature change after 30s and 120s heating (once a day) were recorded. The ratio of the temperature changes after heating provides a proxy for thermal diffusivity. Both instruments documented flooding and snow-ice formation. Flooding was clearly detectable in the simultaneous changes in thermal diffusivity proxy, increased temperature, and heat propagation through the underlying ice. Slush then progressively transformed into snow-ice. Flooding resulted from two different processes; i) after storm-induced break-up of snow-loaded floes for IAOOS8 and ii) after loss of buoyancy due to basal ice melt for IAOOS7. The instrument on IAOOS7 documented basal sea-ice melt over warm Atlantic waters and ocean-to-ice heat flux peaked at up to 400 Wm-2 in winter.
|Acknowledgments||Equipment and participation to the N-ICE2015 Ice camp (organized by the Norsk Polar Institute, Norway on board R.V. Lance, Granskog et al., 2017) were funded under EQUIPEX IAOOS (Ice Atmosphere Ocean Observing System) (ANR-10-EQPX-32-01).|
On both IAOOS7 and IAOOS8 platforms, the ice instrument is a SIMBA (SAMS Ice Mass Balance for the Arctic). A SIMBA comprises a GPS and a 5 m long chain cable hanging through air, snow, sea-ice and ocean. The chain comprises solid-state sensors located every 2 cm measuring temperature at approximately 0.18°C accuracy (resolution 1/16°C). The SIMBA also features a heating mode which can be used to discriminate between different media, especially between snow and ice [Jackson et al., 2013].