OPTIMISTION
OF AN ARCTIC SEA ICE
MODEL USING SPACEBORNE
ESTIMATES
OF ICE THICKNESS
Seymour Laxon, Danny Feltham, and Doug Cresswell
Physically based numerical models are powerful tools in research into polar
climate, where bservations are sparse and limited in time to the relatively
recent past. The construction of these models involves the parameterization
of many physical processes and choices of how to formulate the model - which
components to include, and what to prescribe. The parameterizations and
formulation choices lead to uncertainty in the validity of the model set
up. The aim of the project I am working on is to focus on models of sea
ice, and use the observational data set of remotely sensed ice thickness
developped at UCL (along with other observations) to constrain the uncertainties
in model formulation, increase our understanding of the relative importance
of different mechanisms acting, and construct an optimised model of Arctic
sea ice. This model can then be used with increased confidence to try to
explain the recent changes in Arctic sea ice.
The basis of the model will be a basin-scale dynamic-thermodynamic sea ice model of the Arctic forced by prescribed atmospheric and oceanic forcing, the precise nature of the forcing may be among the formulation choices explored. The ice dynamics will be the elastic-viscous-plastic Hibler-type model, and to begin with most effort will concentrate on the thermodynamic formulation. In addition, one dimensional column models of sea ice will be used and compared to observations from the SHEBA observational experiment.
This work is funded under the NERC funded COAPEC thematic programme, is lead by Seymour Laxon and Danny Feltham, and is collaborative with the Hadley Centre. Doug Cresswell has taken three years leave (starting August 2001) from the Met Office to work on this project at CPOM (UCL).