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Accuracy of sea ice temperature derived from the advanced very high resolution radiometerThe accuracy of Arctic sea ice surface temperatures T(sub s) dericed from advanced very high resolution radiometer (AVHRR) thermal channels is evaluated in the cold seasons by comparing them with surface air temperatures T(sub air) from drifting buoys and ice stations. We use three different estimates of satellite surface temperatures, a direct estimate from AVHRR channel 4 with only correction for the snow surface emissivity but not for the atmosphere, a single-channel regression of T(sub s) with T(sub air), and Key and Haefliger's (1992) polar multichannel algorithm. We find no measurable bias in any of these estimates and few differences in their statistics. The similar performance of all three methods indicates that an atmospheric water vapor correction is not important for the dry winter atmosphere in the central Arctic, given the other sources of error that remain in both the satellite and the comparison data. A record of drifting station data shows winter air temperature to be 1.4 C warmer than the snow surface temperature. `Correcting' air temperatures to skin temperature by subtracting this amount implies that satellite T(sub s) estimates are biased warm with respect to skin temperature by about this amount. A case study with low-flying aircraft data suggests that ice crystal precipitation can cause satellite estimates of T(sub s) to be several degrees warmer than radiometric measurements taken close to the surface, presumably below the ice crystal precipitation layer. An analysis in which errors are assumed to exist in all measurements, not just the satellite measurements, gives a standard deviation in the satellite estimates of 0.9 C, about half the standard deviation of 1.7 C estimated by assigning all the variation between T(sub s) and T(sub air) to errors in T(sub s).
Document ID
19950048855
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Yu, Y.
(Washington Univ. Seattle, WA, United States)
Rothrock, D. A.
(Washington Univ. Seattle, WA, United States)
Lindsay, R. W.
(Washington Univ. Seattle, WA, United States)
Date Acquired
August 16, 2013
Publication Date
March 15, 1995
Publication Information
Publication: Journal of Geophysical Research
Volume: 100
Issue: C3
ISSN: 0148-0227
Subject Category
Oceanography
Accession Number
95A80454
Funding Number(s)
CONTRACT_GRANT: N00014-90-J-1074
CONTRACT_GRANT: NSF DPP-91-16371
CONTRACT_GRANT: N00014-92-J-1191
CONTRACT_GRANT: NASW-2407
Distribution Limits
Public
Copyright
Other

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