Intercomparison of Different Wind–Wave Reanalyses

Abstract
This paper describes the comparison of wind speed and significant wave height data from several reanalyses. The data are assessed against time-averaged altimeter and buoy measurements. The comparisons between the datasets are made in terms of description of short-scale features, monthly means, and long-scale features— namely trends and variability. The results show that although the quality of the datasets in terms of their comparisons with observations differs, most of the long-scale features are equally present in all datasets. The differences between the several wave datasets are larger than those between the wind speed datasets; moreover, differences in wave datasets exist even when the forcing winds used to produce the different wave reanalyses are the same. Most of the discrepancies between the datasets occur in the Tropics, testifying that the physics in that region is still poorly known. The data before the mid-1980s show significant discrepancies also in the Southern Hemisphere, most of which is a consequence of the lack of measurements in those regions in the presatellite era.