Antarctic Sea Ice Response to Tides

Adding Tides to Ice Models

Some problems with models

We have assumed so far that tidal currents are mostly barotropic. That is, currents are uniform with depth. Even if this is true, there are several problems with predicting tidal currents in high-latitude seas. Heights are easier to predict, but are not so interesting in terms of oceanographic effects.


The main prediction problems we have are as follows:

  • Water depth data are sparse in many Antarctic and Arctic regions;

  • Gradients of depth are important, causing current fields to have smaller spatial scales than the height fields; and

  • Stratification causes currents to vary throughout the water column: one can’t always use depth-averaged currents to estimate tidal interactions with ice.

Despite these problems, we find reasonable agreement between modeled currents and various data types that we look at, including buoy and iceberg drift, moored current meters, and vessel ADCP currents. Improved bathymetry is critical to improving the skill of barotropic models.

We will discuss the last point, the role of baroclinicity, in the following slides.