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This data report presents oceanographic observations made
in the Hudson Shelf Valley, offshore of New York, between
December 1999 and April 2000. These observations were made
by the U.S.
Geological Survey (www.usgs.gov) as part of a program to investigate
the transport and fate of sediment and associated contaminants
in the coastal waters offshore of the New York - New Jersey
metropolitan region. The report presents a description of
the field program and instrumentation, an overview of the
data through summary plots and statistics, and the data in
NetCDF, ASCII, and Matlab format.
The objective of this report is to make the data available
in digital form, and to provide summary plots and statistics
to facilitate browsing of the data set. See Harris and others
(in press) for analysis of this data set. See USGS
Studies in the New York Bight (woodshole.er.usgs.gov/project-pages/newyork/) for a description of other
studies and publications.
The experiment was designed to observe sediment transport
and circulation in the vicinity of the Hudson Shelf Valley,
a 20-m deep valley that extends from the shelf edge across
the continental shelf to water depths of about 20 m (figure
1). The head of the shelf valley lies near historic dumpsites
where dredged material, sewage sludge, and other industrial
wastes have been deposited over the last century (Massa and
others, 1996). Some of the material disposed within the New
York Bight and New York Harbor estuary now appears to reside
in the Hudson Shelf Valley, based on elevated concentrations of lead and other metals in shelf valley sediments (ten Brink and others (1996), Mecray and others (1999), ten Brink and others (1998), Mecray and others (2001)).
Past studies using moored current arrays observed strong
shoreward currents (means of 0.10-0.12 m/s) within the upper
portion (20-50 m water depth) of the Hudson Shelf Valley (see
Nelsen and others, 1978; Manning and others, 1994). Harris
and Signell (1999) used numerical models of circulation and
sediment transport to predict that winds from the northwest
could generate up-valley directed currents energetic enough
to resuspend sediment within the Hudson Shelf Valley. These
winds occur frequently, and Harris and Signell (1999) concluded
that resuspension and transport by the associated up-valley
currents may dominate sediment flux within the Hudson Shelf
Valley. While Harris and Signell's (1999) circulation calculations
were consistent with Manning and others (1994) observations,
their transport predictions could not be verified because
simultaneous measurements of suspended sediment concentration
and current were not available.
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Figure
1
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