ASA 127th Meeting M.I.T. 1994 June 6-10

3aAO2. Acoustical rainfall analysis.

Jeffrey A. Nystuen

Ocean Acoust. Div., Atlantic Oceanogr. and Meteorol. Lab., 4301 Rickenbacker Cswy., Miami, FL 33149

Acoustical rainfall analysis (ARA) will provide the means to make needed rainfall measurements in oceanic regions. A prototype ARA algorithm will be presented. It consists of (1) the detection of rainfall in the presence of other underwater noise sources, (2) the classification of rainfall type based on drop size distribution, and (3) the acoustic quantification of rainfall rate. Historical data will be presented to document the acoustic detection of rainfall in oceanic situations. Recent field data demonstrating acoustic classification of rainfall type will be presented and explained using laboratory studies of sound produced by individual raindrops. Classification of rainfall type (stratiform/convective) will allow meteorologists to infer the vertical distribution of latent heat release in the atmosphere. Quantification of rainfall rate can be achieved by several different types of algorithms. Selected quantification algorithms will be presented, compared, and evaluated.