Correlation of real and model wind speeds in different terrains

Wind speeds over a 6-month period from 21 surface stations, 3 upper-wind st ations, and 2 different models are compared. Similar data are used for thre e different topographic regions of New Zealand broadly classed as having lo w, moderate, and high terrain. Mesoscale model winds are obtained in the th ree regions over 300 km by 300 km squares. The dataset is at 40-km grid spa cing but some 20-km winds are also used. Correlation coefficients among the surface wind speeds decrease more quickly with separation the more mountai nous the terrain. Correlation coefficients of observed surface speeds are l ower than for model winds but composites of the observed station winds in e ach region have similar spatial variations to the model winds. An extrapola tion technique for estimating the quality of model wind speed fields is inf erred.