Southeast Coastal Ocean Report
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description of the data that does not rely on human memory or record-keeping reliability;
and a means for searching for particular kinds or subsets of data. Several on-line tools
are available to generate standard metadata, such as those defined by the Federal
Geospatial Data Committee (FGDC). A second generation metadata tool ("MetaDoor"),
created as part of the Caro-COOPS program (www.carocoops.org), is available to anyone
interested in using it (http://nautilus.baruch.sc.edu/twiki_carocoops/ bin/view
/Metadoor/WebHome).
Consistent terminology and consistent formats for data are fundamental to the SEACOOS
IM effort. Accordingly, a data dictionary has been developed which describes the
variables being acquired by SEACOOS and their naming and reference conventions, and
a "common data language" has been adopted. Additional entries and edits to the data
dictionary can be made online, and will form the basis for application cross-references to
the same variable type. The SEACOOS common data language ("SEACOOS CDL"), has
defined format categories, required variables, and required and recommended attributes
in the netCDF file format. In addition, much of the satellite remote sensing imagery
aggregated by SEACOOS is acquired and incorporated using the Portable Network
Graphics (PNG) raster image format.
Normalization
Among the key challenges for the SEACOOS IM system are the needs to merge diverse
in situ and remotely sensed data streams, and to put the combined data into forms that
allow near real-time delivery to various users. The "normalization" process ensures that
the regional data are assembled in a consistent fashion. This normalization has been
accomplished through a central relational database using open source software (Postgres,
see Fig. 3d.1), and documented such that the entire setup can be replicated. Thus, a set of
nodes for redundancy and further data/service functions can be created where sufficient
technical resources and personnel are available. A "by variable" approach has been
adopted that allows for inclusion of quality control information, facilitates queries, and
provides a data structure that is compatible with GIS and modeling applications.
Visualization
The SEACOOS web portal (http://www.seacoos.org) combines powerful database and
file management tools with an interactive internet mapping application (e.g., Fig. 3d.2).
SEACOOS has utilized the open source "MapServer" GIS, which is capable of projecting
a range of different data sources (such as files in shapefile format, raster images, and
geospatially indexed data) on a relational database. Interactive functions allow the user
to select the information to be mapped, and historical information over a limited time
period can be accessed to construct time series maps and animations. It is also possible
to access the data sets that form the basis of the map products.