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The ocean science community is broad: the disciplines of physics, biology, chemistry, and geology are represented. Field research programs may have a global scale. Ocean modelling is done using supercomputers at a number of centers.
Oceanographic datasets tend to be large but inhomogeneous and disaggregated. With the increasing use of satellites for research purposes, there will likely be an order-of-magnitude increase in the size of the datasets. Correspondingly, there will likely be an increase in the homogeneity of the datasets.
A number of major coordinated global oceanographic experiments are planned to take place over the next decade. Most of them are directed to understanding fundamental problems related to global climate and its prediction. In many cases, the line between ocean and atmospheric sciences is not well defined.
TOGA
Tropical Ocean Global Atmosphere
WOCE
World Ocean Circulation Experiment
GOFS
Global Ocean Flux Study
PIPOR
Program for International Polar Research
GSP
Greenland Sea Project
Regional and process studies
The above programs are linked to satellite sensors that are planned or proposed in support of these and other programs:
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Appendix B: Ocean Science Community Network Requirements (Electronic Bulletin Board Message)
Overview
Overall scientific goals and objectives
The ocean science community is broad: the disciplines of physics, biology, chemistry, and geology are represented. Field research programs may have a global scale. Ocean modelling is done using supercomputers at a number of centers.
Oceanographic datasets tend to be large but inhomogeneous and disaggregated. With the increasing use of satellites for research purposes, there will likely be an order-of-magnitude increase in the size of the datasets. Correspondingly, there will likely be an increase in the homogeneity of the datasets.
A number of major coordinated global oceanographic experiments are planned to take place over the next decade. Most of them are directed to understanding fundamental problems related to global climate and its prediction. In many cases, the line between ocean and atmospheric sciences is not well defined.
TOGA
Tropical Ocean Global Atmosphere
WOCE
World Ocean Circulation Experiment
GOFS
Global Ocean Flux Study
PIPOR
Program for International Polar Research
GSP
Greenland Sea Project
Regional and process studies
The above programs are linked to satellite sensors that are planned or proposed in support of these and other programs:
ocean currents
altimeter
GEOSAT
ocean currents
altimeter
TOPEX/Poseidon(NASA/CNES)
ocean currents
altimeter
ERS-1
(Europe)
wind stress
scatterometer
NROSS
wind stress
scatterometer
ERS-1
(Europe)
SST, feature tracking
AVHRR
NOAA
SS, feature tracking
radiometer
MOS-1
(Japan)
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ocean color
CZCS
Nimbus-7
ocean color
SeaWiFS
Landsat-6
sea ice
SAR
ERS-1
(Europe)
sea ice
SAR
JERS-1
(Japan)
sea ice
SSM/I
DMSP
These global ocean science programs have present needs for worldwide computer networking capabilities that will grow as they enter their implementation phases. In the longer term, the ocean science component of the Global Change program will have a worldwide scope that will present an enormous challenge in its needs for coordination, computation, and data management. The program will thus have a correspondingly great need for computer networking.
Typical Ocean Sciences program resources (e.g., observatories, catalogues, archives, supercomputers, international data, other facilities, etc.)
US Data Centers
National Data Centers
National Oceanographic Data Center (NODC)
NASA Ocean Data System (NODS)
National Climatic Data Center (NCDC)
National Center for Atmospheric Research (NCAR)
National Snow and Ice Data Center (NSIDC)
National Space Science Data Center (NSSDC)
National Geophysical Data Center (NGDC)
Specialized US Program Data Centers
TOGA/WOCE thermal data center, Scripps Institution
Sea-Level Data Center, University of Hawaii
Alaskan SAR Facility, University of Alaska
World Data Centers
WDC-A, Oceanography, Washington, DC
Meteorology, Asheville, NC
Geophysics, Boulder, CO
WDC-B, Oceanography, Meteorology, Geophysics, Moscow
International Program Data Centers (partial list)
TOGA Subsurface Data Center, Brest, France
WOCE Hydrographic Program Data Center,?
ERS-1 Data Centers, Frascati, Toulouse, Brest,…
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TOPEX Data Centers, Pasadena, Toulouse, Brest,…
Permanent Service for Mean Sea Level, Bidston, UK
Ocean Drafters Data Center, Ottawa, Canada
Academic Sites (partial list)
University of Miami
University of Rhode Island
University of Wisconsin
University California
SPAN Ocean Network Information Center (SONIC) at the University of Delaware College of Marine Studies. Functions as ocean community network center.
NODS is developing a Global On-Line Director (GOLD) to function as an ocean community distributed catalog. Other catalogs are in existence or being developed at the national data centers and some of the specialized data centers. Nearly all the developing catalog systems assume a networked distributed access.
Supercomputer centers at NCAR and elsewhere are used extensively for ocean modeling. Many US oceanographic centers are linked by the University Satellite Network (USAN) which provides medium speed (56 kbps—223 kbps) access to the supercomputers at NCAR. Additionally, about 20 oceanographic institutions are on regional nets having network affiliations with NSFNET.
Ocean-going research vessels are connected via ATS communications satellite (ground station located at the University of Miami) and thence onto a network (SPAN). There is thus the possibility of networking data from ships anywhere in world to analysis centers.
Island stations and deep-sea moorings collect and often telemeter data in real time. These instruments are often in harsh environments with problems (of saltwater corrosion and thousands of atmospheres of pressure) that are frequently more difficult than those in the space environment.
. Characterization of data needs
(e.g. image transfer (and sizes), interactive remote process control, instrument control, normal interactive access, mail, video conferencing, expected future growth)
File transfer needs
High-resolution digital imagery from satellites
– volume large
ocean charts & sections
– volume moderate
datasets
– volume moderate to large
text
– volume small to moderate
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Data compression techniques are currently employed for transmission of satellite imagery. In such situations, the transmission is critically dependent upon a low bit-error rate, so that error-correcting routines are generally applied, thereby lowering the effective transmission rate.
Large dataset transfers may be done by mailing tapes rather than over a network.
Remote process control is down the line and is not yet commonplace in the ocean sciences.
At-sea data telemetry is sometime used.
Interactive computer access will be used for searching and obtaining datasets.
Mail is, of course, already extensively used for program coordination.
Video conferencing over networks is likely to be tried soon.
Processor, workstation, and network use
Most US ocean research centers have DECNET capability and are on SPAN. A couple of major US oceanographic institutions (University of Washington and Lamont-Doherty Geological Observatory) are not on SPAN. So far, none of the major international centers are networked with the US.
Workstation capabilities are highly variable:
MS/DOS and Macintosh computers with terminal emulation.
SUN workstations.
VAXs, wide variety of mainframes.
Network use is growing rapidly. Global oceanographic experiments will put increasing pressure for installing overseas links to the networks used in the US.
The international oceanographic community is well linked by TELEMAIL (OMNET). A recent printout shows 1800 users in 30 countries. This is extensively used by oceanographers for program coordination and for exchanging limited amounts of data.
A majority of ocean research centers are now with SPAN. Many institutions are on TCP/IP networks such as NSFNET, USAN.
There is general agreement that the system developed to meet the needs of the ocean science community should not be protocol-limited.
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Image-transfer protocols need to be established for the community. Preferably, the protocol that is chosen will be compatible with a wider networking community.
Community Issues and Concerns
Privacy/proprietary rights
Some sites are concerned with privacy.
There is a general concern over proprietary rights, which is possibly less intense where satellite datasets are concerned.
Easy Access vs. system security
Community opinion on this issue is unclear; there may be a division of opinion. Most network enthusiasts seem to be for easy access.
Performance & Reliability
Reliability is important for interactive work: less so for data searching and dissemination.
Formats and standards for ocean science data need strengthening. The GF-3 format is flexible and is widely used internationally but is not universally used.
Whatever formats and standards are used by any one site, the community is looking for overall transparency in system operation.
International collaboration & resource sharing
Major international collaboration: Major data centers are being established (for TOGA, WOCE, GOFS, PIPOR) in the US and other countries:
Canada
France (TOPEX/POSEIDON)
Japan
West Germany
United Kingdom
There is need for international network connections to provide data transfers, mail, and interactive processing.
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