OBJECTIVES
Hypoheses Guiding our Research
- The sea ice cover must be considered an intrinsic part of the ocean boundary layer, such that a model of ice-ocean interaction should not simply transfer stress at the interface between ocean and ice components.
- High frequency motion of the ice-ocean boundary layer (tidal, inertial and ice mechanics induced motion) is a significant component of the ice-ocean momentum balance.
- The impact of ice mechanics on tides in the Arctic ocean is significant.
- This high frequency motion affects the pack ice strain rate, the divergence and shear of leads, in a way that significantly influences ice thickness redistribution and heat/moisture fluxes between the ocean and atmosphere.
Approaches
- This is a joint observation and modelling study.
- We will utilise drifting buoy data from the IABP, and previous Arctic field campaigns.
- We will deploy 2 mesoscale buoy arrays, to observe high frequency sea ice deformation at spatial and temporal scales that are not available in previous data sets.
- We employ a hierarchical model approach designed to elucidate the physical tide-inertial ice-ocean interaction and understand the impact of this on ice area and ice mass balance.
- This will provide insight into the role of sea ice in the Arctic heat and freshwater budgets:
How does sea ice modulate ocean-atmosphere and ocean-ice heat fluxes, i.e. how is this influenced by ice mechanics and high frequency fluctuations in sea ice deformation?
How does this high frequency deformation influence growth and melt of sea ice, relating to freshwater storage and transport throughout the Arctic?
Expected results
- Elucidation of the role of high frequency sea ice deformation on ocean-atmosphere fluxes, salt fluxes to the ocean and sea ice mass balance.
- Development of a barotropic ice-ocean model, including an upper ocean boundary layer with immbedded sea ice, so that net Ekman transport in the upprt ocean includes both ice and water.
- Calibration and validation of this model, driven by 6 hourly winds, against in-situ drift data.
- We will assess the effects of nonlinear ice mechanics and ice-ocean coupling on tidal characteristics, using a hyrarchy of models.
