Marine boundary layer investigations in the False Bay, supported by optical refraction and scintillation measurements

Knowledge on the marine boundary layer is of importance for the prediction of the optical image quality obtained from long range targets. One property of the boundary layer, that can be studied rather easily by means of optical refraction measurements, is the vertical temperature profile. This profile can be compared with the profile, as predicted by the generally accepted Monin-Obukhov (M-O) similarity theory, such as applied in the EOSTAR model, developed at TNO. This model also predicts the atmospheric turbulence profile, for which a validation can be done by means of scintillation measurements. Along these lines we explored the data from the year-round FATMOSE experiment, arranged over the False Bay (South-Africa). Because of the large amount of refraction and scintillation data, supported by extensive data from various local weather stations, we could select the conditions for which the M-O theory is valid and determine the particular conditions where this theory is failing. In the paper model predictions (including Angle of Arrival calculations in non-homogeneous conditions along the 15.7 km path) and associated refraction and scintillation measurements are shown for a representative variety of conditions.