Examination of shipboard measurements of the vertical profiles of mean temperature, humidity and wind speed

Abstract

The suitability of shipboard profile measurements of mean temperature, mean humidity and mean wind over the open ocean is examined on the basis of six hours and 20 minutes of simultaneous profile measurements made from the R/V Acania on 20-21 September 1973 near San Nicolas Island, California. Comparisons of the profiles obtained from the shipboard measurements, as well as the meteorological parameters derived from those profiles are made with results obtained from more stable platforms. Parameters examined include the Richardson number, the friction velocity, the drag coefficient and the roughness length. The drag coefficient and roughness length were found to be generally larger than those obtained from more stable platforms, but the Richardson number and the relationships between the various parameters, as well as the profiles of wind speed and temperature themselves, compare favorably. The results indicate that a ship can be a suitable platform for measuring profiles.