Wave model with ice

Image of the Month - January 2017

Wave model errors depending on whether you take icebergs into account (bottom) or not (top). Taking icebergs into account to compute waves enables to lower the model error in the Southern Ocean (Credits Ifremer)
Mean monthy ice volume distribution (1992-2014) as computed from altimetry (Credits Ifremer)


The Southern ocean high waves are almost a cliché. Even if the highest waves may not be detected there (but rather in the North Atlantic), this Ocean has often very rough sea states. One of its other pecularities is the presence of icebergs, threatening navigation too. Since there's few in situ measurements in the region, satellite observation and modelling are of a particular importance there.

Wave models, which modelize wave heights and directions, did not take into account icebergs at first. But when iceberg distribution maps (from altimetry) were released, biases in wave models and iceberg distributions looked strangely alike... Investigations showed that icebergs are dampening waves, in fact. So, if you don't take them into account, you modelize waves even higher than the actual ones in the iceberg areas.
Altimetry can help for both subjects - significant wave height measurements and iceberg detection. With the CFOSat mission (CNSA/Cnes), a dedicated wave-measurement instrument similar to altimeters will be launched (planned 2018).

See also:

Other website on this subject: