Investigation of the Air-Wave-Sea Interaction Modes Using an Airborne Doppler Wind Lidar: Analyses of the HRDL Data Taken during DYNAMO

Utilizing experienced gained from analysis of TODWL and P3DWL data , we have been analyzing the shipboard HRDL data taken during DYNAMO with a focus on occasions when rain is in the field of view. In particular, investigating if the HRDL data can be used to discriminate between the air motions and the hydrometeor motions occurring simultaneously within the illuminated volumes. A second main objective of the past years' research was to use the HRDL data and the W band radar data taken aboard the USS Revelle to investigate vertical motions within physically thick (optically thin) cirrus layers. Much of the first year's effort has been in acquiring HRDL data, W-band radar data, shipboard flux measurements and observer notes for cases studies with and without rain. This has been followed by a total reprocessing of the raw HRDL data in order to understand what can be obtained from it regarding our main objectives. The HRDL data is recorded using auto-correlations of 6 lags. A main conclusion from our analyses and reprocessing were that 6 lags are insufficient to allow us to discriminate rain from air motions under most conditions. In addition , we also found that using just 10 data points from the HRDL data to obtain 30 meters of range resolution risks a high bias in the LOS wind estimation.
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