The collocation method can be fruitfully applied in SST estimation on
repeated mission tracks. Some applications have been carried out in the western
Mediterranean Sea using ERS1-ERM and TOPEX/POSEIDON data. In this work
some refinements of the method are analyzed to obtain improvements in the
estimates of the stationary component of the SST in the area mentioned above.
Moreover, seasonal variability is investigated, on the basis of the previous stationary
SST estimate, using ERS1 repeats. Some comparisons are made with the circulation
model obtained in the whole Mediterranean Sea from a different elaboration of the
TOPEX/POSEIDON data. They prove that altimetric-derived seasonal variability is
in quite good agreement with such circulation patterns, although they are extremely
weak and display irregular features.