+ Visit NASA.gov + Contact NASA   + Home Collection > NASA  Author > Johnson, J. T.  Author > Kong, J. A.  Author > Kwok, R.  Author > Li, F. K.  Author > Nghiem, S. V.  Author > Wilson, W. J.  Author > Yueh, S. H.  NASA Center > Jet Propulsion Laboratory  Publication Year > 1991-2000 > 1993  Subject > D-F > Earth Resources And Remote Sensing  Availability Options > Order From Other Sources  Item/Media Type > Conference Paper  Note: Start a new navigation search by selecting a link above     Previous Record | Next Record + Back to Results   + Printer Friendly Title: Polarimetric thermal emission from periodic water surfaces Author(s): Yueh, S. H.; Nghiem, S. V.; Kwok, R.; Wilson, W. J.; Li, F. K.; Johnson, J. T.; Kong, J. A. Abstract: Experimental results and theoretical calculations are presented to study the polarimetric emission from water surfaces with directional features. For our ground-based Ku-band radiometer measurements, a water pool was constructed on the roof of a building in the Jet Propulsion Laboratory, and a fiberglass surface with periodic corrugations in one direction was impressed on the top of the water surface to create a stationary water surface underneath it. It is observed that the measured Stokes parameters of corrugated fiberglass-covered water surfaces are functions of azimuth angles and agree very well with the theoretical calculations. The theory, after being verified by the experimental data, was then used to calculate the Stokes parameters of periodic surfaces without fiberglass surface layer and with rms height of the order of wind-generated water ripples. The magnitudes of the azimuthal variation of the calculated emissivities at horizontal and vertical polarizations corresponding to the first two Stokes parameters are found to be comparable to the values measured by airborne radiometers and SSM/I. In addition, the third Stokes parameter not shown in the literature is seen to have approximately twice the magnitude of the azimuth variation of either T(sub h) or T(sub v), which may make it more sensitive to the row direction, while less susceptive to noises because the atmospheric and system noises tend to be unpolarized and are expected to be cancelled out when the third Stokes parameter is derived as the difference of two or three power measurements, as indicated by another experiment carried out at a swimming pool with complicated surroundings. The results indicate that passive polarimetry is a potential technology in the remote sensing of ocean wind vector which is a crucial component in the understanding of global climate change. Issues related to the application of microwave passive polarimetry to ocean wind are also discussed. NASA Center: Jet Propulsion Laboratory Publication Date: JAN 1, 1993 Document Source: Other Sources No Digital Version Available: Go to Tips On Ordering Document ID: 19940015972 Accession ID: 94N20445 Publication Information: gress In Electromagnetics Research Symposium (PIERS), p 770, Number of Pages = 1 Keywords: EMISSIVITY; MICROWAVE RADIOMETERS; OCEAN SURFACE; POLARIMETRY; SURFACE LAYERS; THERMAL EMISSION; AZIMUTH; CLIMATE CHANGE; REMOTE SENSING; RIPPLES; WIND MEASUREMENT; Notes: In its Progress In Electromagnetics Research Symposium (PIERS) p 770 (SEE N94-20403 05-32) Accessibility: Unclassified; No Copyright; Unlimited; Publicly available; Abstract Only Updated/Added to NTRS: 2004-11-03 + Back to Top + Sponsored by the NASA Scientific and Technical    Information Program + 2004 Vision for Space Exploration + Freedom of Information Act + NASA Web Privacy Policy and Important Notices + NASA Disclaimers, Copyright Notice,    and Terms and Conditions of Use NASA Official: Calvin Mackey Page Curator: NASA Center for AeroSpace Information (help@sti.nasa.gov) Last Updated: July 5, 2007