Seasonality in onshore normalized wind profiles above the surface layer

摘要

This work aims to study the seasonal difference in normalized wind speedabove the surface layer as it is observed at the 160 m high mast at thecoastal site H?vs?re at winds from the sea (westerly).Normalized and stability averaged wind speeds above the surface layer areobserved to be 20 to 50% larger in the winter/spring seasons compared tothe summer/autumn seasons at winds from west within the same atmosphericstability class.A method combining the mesoscale model, COAMPS, and observations of thesurface stability of the marine boundary layer is presented. The objectiveof the method is to reconstruct the seasonal signal in normalized wind speedand identify the physical process behind. The method proved reasonablysuccessful in capturing the relative difference in wind speed betweenseasons, indicating that the simulated physical processes are likelycandidates to the observed seasonal signal in normalized wind speed.