Estimating Convective Atmospheric Boundary Layer Depth from Microwave Radar Imagery of the Sea Surface

Abstract Kilometer-scale mottling seen on real and synthetic aperture radar imagery of the sea surface can be linked to the presence of microscale cellular convection (thermals) spanning the marine atmospheric boundary layer. In the current study, it is hypothesized that the typical scale of the mottling, found via standard Fourier spectral analysis, can be used to estimate the depth of the convective marine atmospheric boundary layer (zi) using a modified form of traditional mixed-layer similarity theory for these thermals’ aspect ratio. The hypothesis linking the typical scale of mottling to zi is substantiated using previously published boundary layer results and supporting meteorological and oceanographic data from a number of case studies.

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