Winds from SeaWinds on QuikSCAT & ERS-2 Radar altimeter

 Data are selected when the time difference of measurement between the two instruments is less than 30 mn, and when the distance between the centres of the SeaWinds wind cell and the closest ERS altimeter footprint is less than 12 km.

Every first order statistic is calculated for data selected over 140 orbits (10 days).

Mean values of wind speed differences over 10 days fluctuate between + 1 m/s and - 1 m/s. This large range is partly due to the sampling of different areas over successive 10-day time periods, with different wind speed distributions. For the same reasons the intercept values of the least squares fit fluctuate largely.

The geographical distribution of colocated data shows that the crossing points within 30 mn are located at high latitudes, and mainly in Northern hemisphere. This is due to the particular phasing of the two sun-synchroneous orbits of ERS-2 and QuikSCAT.


Data Period



1999/07/20 - 00437