WIND-PROFILE DIAGNOSIS FROM SURFACE ROUTINE METEOROLOGICAL DATA OVER A COASTAL AREA

A simple algorithm is proposed in order to transform routine surface w ind speed observations near the coast to a wind at the height of the e quilibrium planetary boundary layer as well as to any other height ove r a relatively hat coastal region. The model is based on the well know n internal boundary layer (IBL) concept, Monin-Obukhov similarity theo ry and the resistance law, and describes the effects of the roughness transition from sea to land as well as the effect of stability on the shape of the profiles and the IBL growth. The required input weather d ata are no more than surface wind speed, air temperature and total clo ud cover. Satisfactory agreement was found between measurements at Hel linikon airport and estimations made with the scheme. The introduction of a transition layer above the IBL did not improve the agreement to any significant extent. Mean values of the estimated wind differed by less than 1 m s(-1) from the observed ones, a difference within the ac curacy of the reported rawinsonde values. The rms error varied in the range of 17-22% of the observed average value, giving the best agreeme nt under unstable conditions. The correlation coefficient between the observed and the estimated values of the wind, at the height of the eq uilibrium planetary boundary layer, ranged between 0.74 and 0.90.