DIRECTIONAL CORRELATION-COEFFICIENT FOR CHANNELED FLOW AND APPLICATION TO WIND DATA OVER COMPLEX TERRAIN

Analysis of vector quantities or directional data, such as the variabl es characterizing flow, is of significant interest to geophysical flui d dynamicists. For flows with strong channeling, a new simple correlat ion coefficient is defined. It is demonstrated by application to a mod el of channeled flow that the new correlation captures the flow featur es in the case of channeling better than other correlations taken from the literature. The new correlation coefficient is applied to wind da ta from a mesoscale network of anemometers in complex terrain. A clust er analysis based on the correlation matrix is used to group observati on sites into classes with similar behavior of the channeled flow. Sit es within the same class are not necessarily geographically close. A s imilar behavior of the wind directions indicated by these classes seem s to be more closely related to the orographic features and to the alt itude of the sites than to the horizontal distance between them.