ocean currents
Unlike the tidal currents for example in the north sea which are well known and predictable but always subject to variation such as due to weather. Ocean currents can only be predicted in terms of a long term average drift because there are rotational patterns which move generally in the direction of average drift. Consequentially the drift experienced on a particular day may be in any direction even counter to the long term average drift. This in no way can be extrapolated to previous or subsequent days.
When the search planes first arrived on scene bouys were dropped which will provide very interesting information. How useful will depend on the position relationship to any debris. Hopefully there are a significant number of bouys deployed over a wide area.
What is interesting is the dispersal power of the sea, if you observe two items close to each other it is often amazing to watch them drift apart.
There are particular area of the world where debris accumulates, if this sad saga does continue for many years it may be worthwhile stationing vessels in these area to analyse what turns up.
The BBC had a supposed expert on who postulated that because there is new satellite image 75 miles SW of previous then there is a 1.8 knot drift over the whole period (he failed to use the term knot) fortunately they have just now found an oceanographer who has strongly disputed this.
Rory