Publication Date:
2022-05-26
Description:
Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 55 (2008): 351-364, doi:10.1016/j.dsr2.2007.11.004.
Description:
A technique for the analysis of data from a subsurface moored upward-looking acoustic
Doppler current profiler (ADCP) to determine ice coverage, draft and velocity is presented and
applied to data collected in Marguerite Bay on the western Antarctic Peninsula shelf. This
method provides sea ice information when no dedicated upward-looking sonar (ULS) data is
available. Ice detection is accomplished using windowed variances of ADCP vertical velocity,
vertical error velocity, and surface horizontal speed. ADCP signal correlation and backscatter
intensity were poor indicators of the presence of ice at this site. Ice draft is estimated using a
combination of ADCP backscatter data, atmospheric and oceanic pressure data, and information
about the thermal stratification. This estimate requires corrections to the ADCP-derived range
for instrument tilt and sound speed profile. Uncertainties of ± 0.20 m during midwinter and
± 0.40 m when the base of the surface mixed layer is above the ADCP for ice draft are estimated
based on (a) a Monte Carlo simulation, (b) uncertainty in the sound speed correction, and (c)
performance of the zero-draft estimate during times of known open water. Ice velocity is taken
as the ADCP horizontal velocity in the depth bin specified by the range estimate.
Description:
This work was supported by the NSF Office of Polar Programs
through U.S. Southern Ocean GLOBEC grants OPP 99-10092 and OPP 06-23223, the WHOI
Smith Chair in Coastal Oceanography, and the WHOI Education Office.
Keywords:
Sea ice
;
Ice draft
;
Ice drift
;
ADCP
;
Marguerite Bay
;
Antarctic Peninsula
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Format:
application/pdf
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