A Direct Comparison of Passive Polarimetry and Scatterometry Under Low- and High-Wind Conditions

• Main Authors: Swift, Calvin T., Carswell, James R.
• Other Authors: MASSACHUSETTS UNIV AMHERST MICROWAVE REMOTE SENSING LAB
• Format: Text
• Language: English
• Published: 1997
• Subjects: Meteorology; Test Facilities; Equipment and Methods; *RADIOMETERS; *MARINE METEOROLOGY; *SCATTEROMETERS; OCEAN SURFACE; PASSIVE SYSTEMS; POLARIMETRY; BACKSCATTERING; WIND DIRECTION; WIND VELOCITY; C BAND; LABRADOR SEA; *OCEAN WINDS; C-BAND SCATTEROMETERS; KA-BAND RADIOMETERS; Labrador Sea
• Online Access: http://www.dtic.mil/docs/citations/ADA336859; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA336859

The University of Massachusetts Microwave Remote Sensing Laboratory (MIRSL) gathered coincident active and passive measurements of the ocean surface from the NASA Wallops P3 during the Ocean Wind Imaging (OWI) Experiment. The experiment consisted of five missions flown over the Labrador Sea. Surface winds from 8 to 16 m/s were sampled, and approximately thirty hours of data were collected. The passive measurements were obtained with a novel Ka-band conically scanning passive polarimeter (KASPR) that simultaneously measures the four brightness temperature Stokes parameters by using a correlation receiver. The active measurements were collected by a conically scanning C-band scatterometer (CSCAT) that simultaneously measures the backscatter at four separate incidence angles. Analysis of the passive data shows a wind directional signature in the vertically and horizontally polarized brightness temperature measurements at the high winds. For vertical polarization, the wind direction signature is best described by a two-term Fourier cosine series, while for horizontal polarization, the wind direction signature is described by a three-term Fourier cosine series. This report presents these results as well as summarizes the data obtained and the future analysis plans.