N-ICE2015: Atmosphere

The objective of this project is to understand how atmospheric forcing affects the sea ice mass balance and dynamics in a thinner first-year sea ice regime.

The focus is on the atmospheric boundary layer interactions with the snow and ice cover, and what factors are critical for the growth and melt of the sea ice. Special focus is put on the fate of solar radiation as a major factor in ice melt and how the solar heating is partitioned to snow, ice and the ocean below. Clouds are an important but rather unknown factor in the surface energy balance of the Arctic Ocean, and observations will carried out for cloud coverage and properties. Exchange of greenhouse gases between the ice cover and atmosphere is also quantified. To put the local weather observations in context, a radiosonde programme will also cover the upper atmosphere and provide near-real-time data to global data bases. Overall the proposed research programme will cover key aspects of the atmosphere as driver in the evolution of the sea ice cover.

Core observations will be obtained from a 10 meter weather mast, radiation sensors to measure the downwelling and upwelling radiation components, and eddy covariance systems for turbulent fluxes of heat, momentum and greenhouse gases. An all-sky camera and depolarization lidar will provide information on the clouds. Daily radiosondes will provide information on the upper atmosphere throughout the campaign. On campaign basis the solar radiation transmitted to the ocean will also be observed using divers and ROV, and the CO2 fluxes from sea ice will be measured using the chamber technique. Some autonomous buoys measuring the incident and transmitted radiation will also be deployed away from the ship.