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DATA
DESCRIPTIONS
SCICEX '95 CTD and SSXBT
Profiles
114 Submerged
Ship eXpendible
Conductivity-Temperature-Depth (SSXCTD)
profiles and 5 CTDs were obtained from the
March-May 1995 SCICEX cruise. These data
were processed to provide depth profiles
of temperature, salinity, and sound speed.
The nominal vertical sample interval is
one meter, and the depth range is 12-762
meters (40-2500 feet), which is the range
sampled by a normally functioning
SSXCTD.
SCICEX '95 Bathymetry
The ocean
bathymetry, averaged at 1-minute intervals
along the ship's track for SCICEX 1995,
were loaded into SOARED. In an operational
implementation of SOARED, both historical
and own-ship bathymetry datasets would be
included. The latter could be stored a
number of ways: raw data (i.e., a higher
horizontal resolution), as
inflection
point sampled
data, or even as
imagery. Stored imagery from a 2-D swath
sonar system like SCAMP, or from the
ship's high resolution ahead looking HF
sonar, such as the AN/BQS-15 with
Engineering Change 17 or 18, or the
equivalent ARCI Phase IV ahead looking
sonar might be particularly useful for
certain high sensitivity
missions.
SCICEX '96 High and Low Resolution
Ice Keel Data
The complete set
of SCICEX '96 ice keel data, measured by
the upward looking sonar, was loaded into
SOARED. The data were loaded as 248
distinct straight line segments (with
lengths up to 50 km. The "high resolution"
data are sampled at 1m horizontal
intervals.This substantial dataset, if
called up for a large area, or a smaller
area along with other parameters, can
overtax the SOARED computer RAM and
memory. To avoid this condition, which
will slow the processing of the operator
query, data queries for high resolution
data that encompass more than five legs of
ice keel data automatically stop the
request after the fifth leg is downloaded.
To avoid this problem the data can be
inflection-point
sampled so as to
maintain just enough points to achieve ice
keel depths that are accurate to 30 cm (1
foot). This inflection-point sampled data
is referred to as "low resolution" data in
SOARED.
Downloading large
segments of data to the user's computer
will use all available RAM. Therefore,
these data were inflection-point sampled
to maintain the minimum number of points
to achieve ice keel depths accurate to 30
cm. These inflection-point sampled data
are referred to as "low resolution" data.
Note: to avoid memory overload, the user
should automatically stop a data query
that encompass more than one leg of high
resolution ice keel data after the first
leg is downloaded.
National Ocean Data Center (NODC)
Historical CTD profiles
The NODC
temperature and salinity profiles data
from the World
Ocean Dataset
1998 above 70 N
were extracted and loaded as "Historical"
data. There were 8,720 temperature
profiles and 8,939 salinity profiles.
These were used to compute the sound
velocity profiles contained in
SOARED.
General Digital Environmental Model
(GDEM)
GDEM-5 contains a
world-wide set of temperature, salinity,
and sound velocity profiles on a 5-minute
latitude/longitude grid. The same
locations are provided for each season of
the year, and the data are computed from a
composite of all available historical data
within each 5 x 5 minute cell for a given
season.
For the SOARED
demo, GDEM data from winter and spring
were selected to match the SCICEX dataset,
which consists of profiles from late
winter and early spring. Additionally, the
GDEM data were sub-sampled to a 30 nmi
grid to compensate for the approach to the
North Pole, where 5 minutes of longitude
asymptote to zero nmi spacing. Even at 30
nmi spacing, adjacent GDEM profiles are
nearly identical. A total of 2,865 GDEM
profiles were loaded for each
season.
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