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Accurate Measurements of the Dielectric Constant of Seawater at L BandThis paper describes measurements of the dielectric constant of seawater at a frequency of 1.413 GHz, the center of the protected band (i.e., passive use only) used in the measurement of sea surface salinity from space. The objective of the measurements is to accurately determine the complex dielectric constant of seawater as a function of salinity and temperature. A resonant cylindrical microwave cavity in transmission mode has been employed to make the measurements. The measurements are made using standard seawater at salinities of 30, 33, 35, and 38 practical salinity units over a range of temperatures from 0 degree C to 35 degree C in 5 degree C intervals. Repeated measurements have been made at each temperature and salinity. Mean values and standard deviations are then computed. The total error budget indicates that the real and imaginary parts of the dielectric constant have a combined standard uncertainty of about 0.3 over the range of salinities and temperatures considered. The measurements are compared with the dielectric constants obtained from the model functions of Klein and Swift and those of Meissner and Wentz. The biggest differences occur at low and high temperatures.
Document ID
20160005727
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Lang, Roger (George Washington Univ. Washington, DC, United States)
Zhou, Yiwen (George Washington Univ. Washington, DC, United States)
Utku, Cuneyt (Scientific and Technical Research Council of Turkey Ankara, Turkey)
Le Vine, David (NASA Goddard Space Flight Center Greenbelt, MD United States)
Date Acquired
May 3, 2016
Publication Date
January 6, 2016
Publication Information
Publication: Radio Science
Volume: 51
Issue: 1
ISSN: 0048-6604
Subject Category
Oceanography
Earth Resources and Remote Sensing
Report/Patent Number
GSFC-E-DAA-TN31696
Funding Number(s)
CONTRACT_GRANT: NNX09AU72G
Distribution Limits
Public
Copyright
Other
Keywords
Measurements
L Band
Seawater