Statistical Comparisons of Satellite and Model Wave Climatologies

Satellite and model climatologies of monthly mean wave height are compared globally and in the North Atlantic. All of the tested climatologies give a broadly consistent picture of regional variations in wave climate. There are however some systematic biases between climatologies and all the climatologies are subject to root-mean-square (rms) errors of the order of 0.1 meters or more. The global model climatology (WAM-ERA) is marred by large errors in some regions, and by a general tendency to underestimate large waves and overestimate small waves. Errors in climatologies based on a single satellite result primarily from sparse sampling and are largest where variability within a calendar month is greatest. A model of the North Atlantic (AES-40) is largely consistent with the satellite measurements, and the estimated rms errors of this model are less than the estimated satellite errors in the stormy northern North Atlantic of the winter period.