Three posters were prepared for the

Bjerknes Centenary 2004: Climate Change in High Latitudes.

Reduced images of the posters are shown below with respective abstracts.  Click on any poster image to download a PDF file (approx 2 MB each).


Under the Arctic Ocean Models Intercomparison Project (AOMIP), results from AWI, IOS   and LANL models are compared with respect to circulation, temperature and salinity   through the Atlantic Layer. Evaluations are performed as functions of depth and of time   over the period 1950 - 2000. Goals include identifying differences among AOMIP models   leading to different representations of the Atlantic Layer.

 The approach in AOMIP is to integrate all of the models in as nearly the same way as   possible (common initialization, common forcing, etc.) from Jan 1948 through 2000 (or   further). Goals are (1) to see how model results differ among themeselves and from   observations, (2) to discover the reasons for different results, and (3) to identify ways for   models’ improvement. This poster is concerned with (1) seeing how model results differ.


Along the eastern side of the N Pacific, shallow flows characterize the eastern limbs   of the subtropic and subpolar gyres. Beneath the surface, and sometimes at the   surface, poleward flows overlying the continental slope persists from Mexico to the   Aleutian Arc. These surface and subsurface flows here define ‘California Currents’.

 Shallow flows in the Arctic tend to form an anticyclonic and a cyclonic gyre.   Beneath  the surface, and sometimes at the surface, circumbasin boundary flows   overlie the slopes. Such themes are repeated in ocean basins and marginal seas   throughout the world. Why? The suggestion is that, of all ways ocean currents can   organize, largely independently of applied forcing, the overwhelming majority of   outcomes resemble California Currents. This is especially illustrated in the Arctic.



We utilize one of the AOMIP (Arctic Ocean Model Intercomparison Project) models to examine the influence that Arctic tides may exert upon the long term climate of the ocean and ice system. Output from a previous tidal model provides a parameterization of vertical mixing in the water column as well as affecting lead opening and mobility of sea ice. Results include loss of heat from the Atlantic Layer, leading to sea ice reduction which is offset by higher growth due to fracturing the ice cover. Climatic consequences are considered beyond the Arctic.