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Listening to Raindrops and Other Curious Ways to Measure Rainfall Eyal Amitai, NASA/GSFC, and colleagues have listened to raindrops at sea using hydrophones 2000 meters below the surface. This promises to become a reliable method to obtain data from remote areas in the oceans and contribute to a global picture of rainfall. Scientists need these measurements to support climate studies of the distribution and intensity of global rainfall patterns. Deep water acoustical measurements of rainfall are compared to high resolution ground radar observations for the first time. The open sea measurements of underwater ambient sound were made from a sub-surface mooring near Methoni, Greece in 2004. The acoustical measurements were at 60, 200, 1000 and 2000 m depths. Simultaneous ground-based polarimetric X-band radar observations were made over the acoustic mooring. Comparisons show acoustic detection of rain events and storm structure that are in agreement with the radar observations. Results from the comparison between the underwater sound pressure level at different depths and the observed-radar reflectivities will be presented in session AS1.03. “For several years we have known that high correlation exists between radar reflectivity and underwater sound of rainfall based on observation in shallow water, but now, for the first time such correlation is found in the deep sea. The new results demonstrate the potential for evaluating ground and space-based radar rainfall observations using underwater sound. The listening area is proportional to the hydrophone depth, and for deep hydrophones it is in the order of the radar footprint,” says Dr Amitai. Session: AS1.03 Observation, Prediction and Verification of Precipitation | >>programme See for more news on precipitation observation:
Silas Chr. Michaelides silas@ucy.ac.cy |