The availability of reliable sources of wind and wave data for climate studies used to be limited especially in enclosed basins. High quality numerical weather prediction models changed this situation. The degraded quality of early stages of models and the frequent changes to improve these models introduce inconsistencies that limit the use of operational model results for wind and wave climate studies. Reanalysis model fields, e.g. ERA-Interim, ERA-20C and the forthcoming ERA-5 of ECMWF, which are produced by frozen models and extend to several decades, are attractive source of data for climate computations. ERA-20C covers a period of 111 years (19002010) at a coarse horizontal resolution of similar to 150 km. It assimilates minimal amount of data making it more homogeneous than other reanalysis data sets. The suitability of this data set together with its sibling ERA-20CM (only model integration without any data assimilation) for wind and wave climate studies in the Black Sea as an example of a small enclosed basin is investigated.