iris ocean cable, inc. · iris ocean cable, inc. annual report—2004 rhett butler background iris...

IR IS O C E A N C A B L E , IN C .ANNUAL REPORT—2004

Rhett Butler

Background

IRIS Ocean Cable, Inc. (IOC) is a not-for-profit corporation created by The IRIS Consortium

(IRIS) to own and operate undersea cable systems for the scientific community. IOC was

established in 1990 to receive ownership of the Guam–Japan section of Trans-Pacific Cable-1

(TPC-1) telephone cable from AT&T. IOC co-owns TPC-1 with the Earthquake Research

Institute (ERI) of the University of Tokyo, which received Japan’s KDD share of TPC-1. IOC

holds a license from AT&T for use of space in the Guam Cable Station for the TPC-1 terminus

equipment. In 1996, IOC was given the Hawaii-2 telephone cable by AT&T, and a license for

space in the Makaha Cable Station on Oahu. This cable runs from Oahu, Hawaii, to the California

continental shelf. In 2003 IOC was given 81 km of spare fiber optic, currently stored in Guam, by

AT&T. IOC is a member of the International Cable Protection Committee, and in this forum

has developed a number of interactions with the international undersea telecommunications

community. Appendix A contains a summary of IOC cable systems, license agreements, and

equipment.

Director

Rhett Butler stepped down as Director of IRIS Ocean Cable, Inc., at the end of 2003. Dr. Butler

served as the IOC Director since its incorporation. As the Program Manager for the IRIS Global

Seismographic Network, Dr. Butler will be focusing GSN interests in broad oceanic coverage of

the Earth using a variety of ocean technologies, including cables. At The IRIS Consortium’s

request, Dr. Butler agreed to help IOC during this interim transition.

First Generation Fiber Optic Telecommunications Cables

AT&T approached IRIS in 2002 regarding the impending retirement of first generation fiber

optic telecommunications systems. At the request in October 2002 and January 2003 of the IRIS

Executive Committee and the Board of Directors of IOC, and with encouragement from the US

National Science Foundation, the Director entered into discussions with AT&T regarding the

transfer of these Cable Systems to IOC for use by the scientific community. With the strong

interest expressed by the NSF Director of Oceans Sciences to the IOC membership (see

Appendix B) on May 7, during the IOC Annual Meeting in May 2003 the following resolution

was adopted to enable IOC to work with NSF and AT&T (and their partners) for the re-use of

the fiber optic systems for science:

The President and Director will work with the National Science Foundation

1) to negotiate appropriate agreements to acquire for re-use by the scientific

community retiring fiber optic telecommunications cable systems and their spares,

2) to conclude such agreements as cable systems become available, and

3) to arrange for the funding of the costs for these through the National Science

Foundation.

The cable systems under discussion are: Guam-Philippine-Taiwan (GPT), Trans-Pacific Cable-3

(TPC-3), TPC-4, Hawaii-4 (HAW-4), HAW-5, Pacific Rim East, Trans-Atlantic-8 (TAT-8),

TAT-9, TAT-10, and TAT-11. AT&T has offered to donate the Cable Systems, surplus cable,

and system spares, and to negotiate license space in the respective cable stations. AT&T has

provided detailed cable routes and historical cable repair information for all these systems, as

well as substantial informal advice and information. These Cable Systems have 0.5-1 Gb/s

telecommunications capacity and offer several kilowatts of power at the seafloor.

Because the cable equipment maintenance and storage facilities were sold by AT&T several years

ago to Tyco Telecommunications, discussions have also been initiated with Tyco to discuss

continued storage of the surplus cable and repeaters now stored at Tyco facilities. These

discussions have also led to the release to the scientific community of original system drawings

and schematics of the cable repeaters and station plant.

The National Science Foundation has given approval to the University of Hawaii to re-focus the

MRI funded Aloha Observatory Project for connecting the Hawaii Ocean Time Series (HOTS)

site to HAW-4 fiber cable instead of the previously proposed ANZCAN-D coaxial cable. This

permits UH to use NSF funds in support of the Hawaii-4 cable re-use activities. With NSF’s

permission and encouragement, UH offered to fund the relocation to Honolulu for the Guam-

based GTP surplus cable and spares offered to IOC. In May 2003 IOC accepted ownership of 3

pans of GPT fiber optic cable (80 km of fishbite, 1 km of double armored) and 3 SL280

repeaters. With bridge funding from NSF Ocean Science to The IRIS Consortium for arranging

the re-use of retiring fiber optic systems, IRIS has been paying the storage costs ($3,800/month) at

the Tyco facility on Guam as UH makes shipping arrangements.

On behalf of IOC, The IRIS Consortium in June 2003 presented NSF with an initial proposal to

accept all of the 7 cable systems then being offered by AT&T: GPT, HAW-4, TPC-3, TAT-8,

TAT-9, TAT-10, and TAT-11. Given the short timing and large cost for this whole effort, N S F

requested a Report and a smaller Proposal to provide bridge funding during interim discussions

with AT&T and as plans within NSF and the scientific community developed within the context

of the ORION initiative. The Report is available on the IRIS website along with substantial

background material and documentation (see www.iris.iris.edu/cable), and was used as the basis

for an IEEE paper submitted as part of the proceedings of the Scientific Submarine Cable

Workshop at the University of Tokyo (see Appendix C) in June 2003. The IRIS Consortium

submitted a proposal in June for $199,055 to NSF Oceans Sciences, which was accepted and

funded, to serve as 6-months bridge funding toward the acquisition of these cables systems and

their spares.

Many former AT&T/Tyco engineers who designed these Cable Systems have been offering their

assistance in the Cable re-use effort. These people, led by Mr. Mark Tremblay, bring both key

expertise and have extensive good-will contacts throughout the AT&T and Tyco organizations.

Mark Tremblay is serving as a consultant to the IRIS Consortium under the NSF bridge funding.

A group of 15 current and former AT&T/Tyco cable system engineers met with people from

IOC, University of Hawaii, and Rutgers in September 2003 to review technical issues regarding

cable re-use. The executive summary of this Workshop Report is attached in Appendix D, with the

first finding that “There appears to be no significant technical roadblocks in re-use of the cable

systems for ocean observatory arrays.”

In June 2003 NSF asked the Dynamics of Earth and Ocean Sciences (DEOS) Committee to

independently review re-use of the fiber optic cable system. The DEOS Cable Re-use Committee

was Chaired by Jack Sipress, retired vice-President of Tyco Telecommunications and formerly

of AT&T Submarine Systems. IOC provided substantial material regarding its work and

contact with AT&T and Tyco for the Committee. The executive summary of this Committee

Report, released in September 2003, is attached in Appendix E with the first principle finding

that, “There are no fundamental engineering limitations that would prevent the effective re-use of

retired cables either in-situ or located.” The Report recommended saving key cable system

components. Following this Report, the DEOS Committee offered their scientific prioritization

of available cable systems, and recommended in October 2003 (see Appendix F) further study of

the costs for cable re-use, the trade-off versus using buoys instead, and the acquisition of spare cable

(the costs for moving/storage should not exceed $200K/yr), and also noted that, “The use of

existing cables by other scientific interests may well have priorities quite distinct from those

expressed in this report.”

AT&T offered a draft cable transfer agreement April 2003 based upon prior agreements for

TPC-1 and Hawaii-2. The principal difference in the new agreement is the addition of an

Insurance Clause to provide AT&T and the cable system owners more liability protection, since

IOC is a not-for-profit corporation without substantial financial assets. Working with The IRIS

Consortium’s insurance agent and advisors, and in consultation with a marine insurance specialist

recommended by NSF, IOC submitted a revised insurance clause to AT&T, which is being

reviewed by their risk management team.

There have been substantial changes in AT&T management during 2003. AT&T Submarine

Systems Operations and Maintenance has been restructured and IOC’s two primary contacts were

moved elsewhere in the company. However, good working relationships with the next levels (above

and below) of management, and the interest and commitment of the AT&T team have made this

transition smooth.

IOC has entered into broad discussions with the consortium of European owners (for the Trans-

Atlantic Systems), and with KDDI Japan and New Zealand Telecom in the Pacific regarding

scientific re-use of cable systems. KDDI and New Zealand Telecom have openly expressed their

willingness to work with the scientific community for transfer of cable systems for scientific re-

use. There have been some concerns regarding tax liability questions faced by KDDI in donating

cable systems for science. IOC has been advised that these issues have been informally resolved

within Japan, both by KDDI and from communications with JAMSTEC colleagues.

The consortium of European owners of the Trans-Atlantic systems have expressed that they do not

feel that IOC affords sufficient liability protection to permit them to transfer cable systems to

IOC for science. AT&T has spoken directly to the their partners on behalf of the US scientific

community, without success. IOC has worked with the European scientific community, but again

without effect on the European owners’ position. Nonetheless, the European owners are amenable to

scientific re-use of the Trans-Atlantic systems, but a different transfer model must be found which

affords more liability protection. Possible ideas may be NSF itself, another US government

agency, or a State University.

As part of the retirement of the TAT-9 and TAT-11 cable systems, AT&T plans to close the

Cable Station in Manahawkin, New Jersey, which is situated close to Rutgers University in a

wildlife sanctuary. Following introduction by IOC, Rutgers is now reviewing with AT&T the

possible transfer of the Cable Station to Rutgers.

With the strong interest of NSF and members of the scientific community, but with limited

resources afforded by The IRIS Consortium’s NSF bridge funding, IOC has approached cable

re-use in saving key systems and spare equipment that keeps the scientific community’s options

open in the future. IOC has worked with AT&T to obtain costs for license space in the Cable

Stations and has sought to extend as much as possible the time frame when license space costs

would begin to be incurred. IOC has also arranged for storage of key station equipment in the

Cable Station for a limited time, without license space fees. The effort is to avoid where possible

up front costs prior to and during the development of scientific re-use capability for these systems.

These efforts are based upon good-faith discussions by the scientific community with AT&T, and

result in implied commitments by the scientific community.

IOC has worked closely with NSF to bring awareness of these implied commitments, so that

long term relations between AT&T and the scientific community may be maintained for years

into the future (and for the retirement of future cable systems). The principal implied

commitment has to do with the storage of key equipment in the cable station. When this occurs,

the scientific community is obligated to clean up after itself, should it not need the equipment at a

later date. AT&T and their partners typically close their books on a cable system 6-12 months

after retirement. If the equipment is not removed by then, the onus falls to the Cable Station

owner (AT&T) for costs. For example, the cost of removing a cable system is about $50K

(AT&T estimate). Hence, although IOC may be able to arrange to store the Hawaii-4 equipment

at the Makaha Cable station for free for some time, if the project cannot for some reason be

completed, there is an implied cost of about $50K to be covered for clean up.

IOC has worked closely with NSF in decisions regarding which systems and key equipment to

save. Scientific focus on Hawaii-4 (Aloha Observatory) is a top priority. Saving key spares from

Trans-Atlantic systems preserves the possibility for future re-use (perhaps for coastal or deep sea

observatories), as well as providing essential systems for developing Hawaii-4 re-use capability.

These Atlantic efforts are coordinated with Rutgers University, which is providing free storage

space for spares and key equipment. Mark Tremblay (The IRIS Consortium’s consultant) is

working with AT&T to make arrangements for moving the equipment to Rutgers following

ownership transfer to IOC. The University of Hawaii is working with Rutgers and local New

Jersey AT&T/Tyco engineers toward an NSF proposal for the technical development of the

Hawaii-4 system re-use.

IOC was offered all the spare TAT-9, TAT-9, TAT-10, and TAT-11 cable and repeaters

stored in the Tyco Baltimore depot in October. After careful review with and the concurrence of

NSF, the decision was to decline this offer, except for saving 5 repeaters for future observatory

development of use. The transfer agreements are ready to be signed by IOC, after which the

repeaters will be moved to Rutgers for storage.

The TAT systems (and Pacific systems) routinely log in-situ temperature data. IOC has been

working with AT&T and Rutgers to have this data set saved for science.

The prime focus on Hawaii-4 has led to discussions of storing key equipment in the Makaha Cable

Station, where IOC currently has license space for the Hawaii-2 analog cable system (H2O).

TPC-3 has identical hardware, and the intention is to save key equipment from TPC-3, stored at

University of Hawaii. For the Hawaii-4 system at the Point Arena Cable Station in California,

discussions at the recent International Ocean Network Meeting in Berkeley in December 2003

indicates interest by scientists at UC Berkeley and Oregon State University in re-use of the

California end of the Hawaii-4 system. If interest is strong and the case can be made to NSF, then

perhaps the key Hawaii-4 equipment in the Point Arena Cable Station may be saved or stored in

place (in any case, key laser components would be salvaged for Hawaii-4).

The status of negotiations, discussions, and activities for the Pacific and Atlantic Cable Systems

(in coordination with NSF) are briefly summarized:

Pacific Cables

The Cable Owners have agreed in principle to transfer the cables for science, subject to an

acceptable Transfer Agreement.

GPT

The system is now retired from service. There is no NSF funded project for the GPT cable

system and no action is being taken to save this system for re-use at this time. Three pans of fiber

cable (81 km) and three repeaters have been transferred to IOC, and are currently stored on Guam

($3,830/month).

TPC-3

The system is now retired from service. There is no NSF funded project for the TPC-3 system at

this time. There is no Japanese interest in the KDDI section of the TCP-3 system. Key

components of the transmission system from Makaha will be saved and moved to the University

of Hawaii. Significant spare cables and repeaters are located in Honolulu, and the decision on

these will depend upon costs and schedules to be coordinated with NSF.

HAW-4

The system is now retired from service. NSF has a funded project, Aloha Observatory, with an

interest in using this Cable System. Efforts are in progress to store the Hawaii-4 equipment in

place at the Makaha Cable Station. AT&T has quoted license space for Makaha at about

$76/sq.ft. (About $27K/yr for space comparable for Hawaii-2). The storage of Hawaii-4

equipment at the Point Arena Cable Station will depend upon the interest of NSF and west coast

scientists. Licence space in Point Arena is quoted at $50/sq.ft. ($17K/yr for space comparable for

Hawaii-2). Significant spare cables and repeaters are located in Honolulu and Portland, and the

decision on these will depend upon costs and schedules to be coordinated with NSF.

HAW-5

This system will probably retire in 1-3 years.

TPC-4

This system is currently planned for retirement in mid-to-late 2004. There is strong, vocal

scientific interest in this system.

PacRim East

This system will probably retire in 2-3 years. There is strong, vocal scientific interest in this

system.

Atlantic CablesAll of these systems are now retired from service. Although AT&T has been willing to transfer

these systems to scientific re-use, the European Owners have not agreed to transfer the systems to a

not-for-profit entity such as IOC. The Owners are currently in the process of removing all cable

from the European continental shelf. The US end will remain intact into the respective Cable

Stations, opening the possibility for future scientific re-use if an appropriate and acceptable new

ownership model is found (possibly a US or State government agency). The donation of spare

cable from AT&T has been declined. Five system repeaters are in the process of being transferred

to IOC, and moved to Rutgers. Plans are in progress to move spare key equipment stored from

the AT&T warehouse in Randolf NJ to Rutgers.

TAT-8

Transmission equipment stored in place at the Tuckerton Cable Station will be moved to

Rutgers.

TAT-9 and TAT-11

One set of transmission equipment from either TAT-9 or TAT-11 will be moved to Rutgers.

AT&T and Rutgers are discussing the possible transfer of the Manhawkin Cable Station to

Rutgers.

TAT-10

All equipment has been disposed by AT&T. Compatible TAT-9 or TAT-11 equipment will be

saved at Rutgers.

Existing IOC Coaxial Cable Systems

Hawaii-2

The Hawaii-2 Observatory (H2O) near 28°N & 142°W continued to operate and provide real-

time scientific data from the seafloor up to the system maintenance and upgrade cruise in May

2003. The GSN station H2O provided greater than 99% data availability. A new power system

was installed at the Makaha Cable Station in January 2003, replacing the old, original HAW-2

power plant. Space requirements within the Cable Station have been reduced, as requested by

AT&T.

In May the Junction Box was retrieved for upgrade and refurbishment by WHOI and University of

Hawaii. In October 2003 shortly following the redeployment cruise, the H2O seafloor system

ceased operation, and no scientific data now are available from H2O. NSF has requested a review

of the situation and this review is currently in progress. There appears to be no problem with the

IOC owned cable system or shore-based power system components.

IOC currently has license space in Makaha costing $13,880/yr.

TPC-1

The Earthquake Research Institute of the University of Tokyo deployed its GEO-TOC

instrumentation into the TPC-1 Cable System in 1997 at a site near 30°N, 140°E, using the cable

ship KDD Ocean Link to install and splice the sensors package into the cable. IRIS coordinated

with the Guam Cable Station. Data have been recorded at the ERI Data Center via a telemetry

link from the Ninomiya Cable Station, and are accessible through anonymous ftp from

geotoc1.eri.u-tokyo.ac.jp/win. Data converted to SEED format have been distributed to the IRIS.

In late 2002 a shunt fault occurred in the cable in Tokyo Bay near the Ninomiya Cable Station

due to a turbidity flow caused by a typhoon. The Japanese have decided not to repair the system.

ERI continues passive monitoring of the cable voltage in Guam as a part of its geomagnetic

program.

IOC and ERI remain the legal owners of the TPC-1 equipment at Guam and IOC holds the

license for space in the Guam Cable Station. The license for Guam was renewed in 1997 for a 10-

year period at a cost of $3,300 per year, which is reimbursed by the University of Tokyo under a

Memorandum between ERI and The IRIS Consortium.

Since TPC-1 is no longer being actively powered, IOC asked AT&T for a quote to remove and

dispose all original TPC-1 equipment from Guam. The costing is being done in the context of

other AT&T equipment removal as part of the decommissioning of GPT and TPC-3. If the

work can be accomplished and invoiced prior to April 1, 2004 ERI has indicated that it will cost

share. After this date, further discussions must be made under new University of Tokyo

administrative rules. IOC will request funds from NSF for its share of the TPC-1 de-

commissioning effort.

International Cable Protection Committee

In August 2003, Rhett Butler became the IOC Representative to the International Cable

Protection Committee. In writing to the ICPC, IOC acknowledged Dr. Chave’s contributions:

“It has been a pleasure to have Alan Chave serve as our representative since the early 1990's.

I know that Alan has been very active in the ICPC in bringing an awareness of the scientific

use of undersea cable systems, and the activities of scientific programs which may

potentially affect undersea cables. His efforts have been appreciated. I look forward to his

continuing participation at an informal level.”

Appendix A. IOC systems, license agreements, and equipment.

TPC-1 (Guam-Ninomiya Segment)

Transferred on November 1, 1990 from AT&T and KDD to IOC and Earthquake

Research Institute of the University of Tokyo. The system is jointly owned by IOC and

ERI.

IOC has a license agreement for space in the Tanguisson Guam Cable station since January

17, 1992. This agreement was extended on January 17, 1997 for another term of ten years.

The yearly cost is $3,300.

Hawaii-2

Transferred on October 15, 1996 from AT&T to IOC.

IOC has a license agreement for space in the Makaha Cable station since November 4,

1996. This agreement was extended on November 4, 2001 for another term of ten years.

The yearly cost is $13,880/yr for the first five years through 2006, and $15,880/yr for the

next five years through 2011.

In 1995 IOC obtained in independent valuation of $7,321,500 for the Hawaii-2 Cable

System from Margus Co. Inc. The IRIS Consortium used this asset for $2,195,000 in

institutional cost sharing as part of the NSF funding for the Hawaii-2 Observatory system.

GPT system spares

Transferred on June 1, 2003 from AT&T to IOC:

1 Cable Pan (21 ft diameter) with 0.968 km SL-DA Cable

1 Cable Pan (21 ft diameter) with 40.410 km SL-FBP Cable

1 Cable Pan (21 ft diameter) with 40.425 km SL-FBP Cable

3 SL-280 Cable System Repeaters

Equipment is currently stored on Guam at the Tyco Depot at of cost of $3830/month.

Appendix B. Letter from NSF Ocean Sciences

Appendix C.

IOC Report to Scientific Submarine Cable 2003 Workshop, University of Tokyo

Scientific Use of Fiber Optic Submarine Telecommunications Cable Systems

Scientific Submarine Cable 2003 Workshop Report, University of Tokyo

Additional information may be found at www.iris.iris.edu/cable/info.htm

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Scientific Use of Fiber-Optic Submarine Telecommunications Cable Systems

Rhett ButlerDirector, IRIS Ocean Cable

1200 New York Avenue NW, Suite 800Washington, DC 20005

[email protected]

Introduction. The first generation of fiber optic submarine cables began a revolution for telecommunication. Thebandwidth available in these systems truly created the information superhighway across the oceans between NorthAmerica, Europe, Japan, and other centers of digital culture. The development and installation cost of these systemsexceeded $2,000,000,000. These electro-optical systems, though state-of-the-art in their time, have now beensurpassed by purely optical systems with vastly greater capabilities. Because the second-generation systems arepurely optical, using in-line lasers to amplify the signals rather than electro-optical regenerators, they may beupgraded “in place”—by changing only the terminal equipment the bandwidth may be increased by 1-2 orders ofmagnitude. This versatility coupled with the current underutilization of existing fiber capacity (estimated at less thana 10%), has led to the decision of telecommunications companies to retire their first generation fiber optic systemsmore than decade earlier than originally planned. This presents an extraordinary opportunity for science.

Cabled Seafloor Observatories are essential to the Ocean Sciences (NRC, 2000), and the intellectual merit andbroader impacts of these observatories have been discussed in a succession of NSF workshops and NRC reports.These fiber optic telecommunications cables being retired by the telecommunication industry are now being offeredfor scientific reuse by AT&T, and are in discussions with the overseas owners. These Cable Systems include threePacific systems—Hawaii-4, Trans-Pacific Cable-3 (TPC-3), Guam-Philippine-Taiwan (GPT)—and four AtlanticSystems—Trans-Atlantic-8 (TAT-8), TAT-9, TAT-10, and TAT-11 (Figure 1). The transfer of these systems toscience is currently in negotiations (July, 2003). A facility for ownership transfer is IRIS Ocean Cable, Inc. (IOC), anot-for-profit corporation formed by The IRIS Consortium in consultation with the National Science Foundation toacquire ownership of retired telephone cables for science. IOC currently owns two retired coaxial telephone cables:TPC-1 (Guam-Japan) with the University of Tokyo (Kasahara et al., 1998) and Hawaii-2, which serves the NSF-funded Hawaii-2 Observatory (H2O) (Butler et al., 2000).

Figure 1. The TPC-1 and Hawaii-2 coaxial submarine telephone cables were transferred for scientific use in the1990’s. Seven first generation fiber optic Cable Systems are now being retired, and are being considered forscientific use.



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Four of these fiber systems—TAT-8,TAT-10, TAT-11, and GPT—havealready retired, and the other threeaforementioned systems will beretired by the end of the year. Thereare three additional first generationsystems in the Pacific (TPC-4,Hawaii-5, and PacRimEast, seeFigure 2.) that will likely be retiredin the coming years. Because thetelecommunications companiesmove quickly (typically with a six-month time frame) after a system’sretirement to dispose of theequipment and spares (and in Europeand Japan to remove cable from thecoast) it is essential to act now if thescientific community wishes toretain any options for using thesecables for science in the future. Asthe scientific community and NSFdevelops consensus for use of thesesystems for science, focus must bedirected to establish a framework forthe basic infrastructure andmanagement necessary towardacquiring these systems for scientificuse.

The Director of IRIS OceanCable—in consultation with theNational Science Foundation and

with approval of the IRIS Executive Committee and Board of IRIS Ocean Cable, Inc.—has been actively workingwith AT&T and their Cable System partners since July 2002 to make arrangements for the scientific re-use of thesefirst generation fiber systems. There are no fundamental impediments for the Pacific Cable Systems—transfer ofsystems and spares has been agreed to, in principle, by the respective System Owners (a draft system transferagreement has been submitted for consideration, a transfer agreement for GPT spares has already been signed),license space in cable stations (a draft license agreement has been submitted for consideration) and storage space forspares is being negotiated. The donation of equipment schematics encompassing both Pacific and Atlantic Systemshas been accomplished. For the Atlantic Systems, discussions are underway with AT&T and their 50 Europeanpartners.

Scientific Opportunities. The scientific importance of cabled seafloor observatories has been fully documented in aseries of National Research Council reports, NSF sponsored workshops, and National Ocean Partnership Programreports. The Executive Summary of Illuminating the Hidden Planet, the Future of Seafloor Observatory Science(NRC, 2000) begins

Earth's oceans are essential to society as a source of food and minerals, a place of recreation, aneconomic means of transporting goods, and a keystone of our national security. Despite our reliance onthe ocean and its resources, it remains a frontier for scientific exploration and discovery. Scientistshave been using ships to explore the ocean with great success over the past 50 years and this mode ofexpeditionary science has led to remarkable increases in oceanographic knowledge. A ship-basedexpeditionary approach, however, is poorly suited for investigating changes in the ocean environmentover extended intervals of time. To advance oceanographic science further, long time-seriesmeasurements of critical ocean parameters, such as those collected using seafloor observatories, areneeded (NRC, 1998).

Figure 2. First generation fiber optic telecommunications cables in thePacific are shown, with their installation dates and nominal bandwidth (perfiber pair).



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Figure 3. Maps of TransAtlantic Cables highlighting TAT-8, TAT-9, TAT-10, and TAT-11 with respect toother cable systems. Note locations (green squares) of last AT&T repeaters for TAT-8, TAT-9, and TAT-11.TAT-10 has all AT&T repeaters (complete TAT-10 map shown in Figure 4).



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For the purpose of this report the term “seafloor observatories” is used to describe an unmannedsystem of instruments, sensors, and command modules connected either acoustically or via a seafloorjunction box to a surface buoy or a fiber optic cable to land. These observatories will have power andcommunication capabilities and will provide support for spatially distributed sensing systems andmobile platforms. Instruments and sensors will have the potential to make measurements from abovethe air-sea interface to below the seafloor and will provide support for in situ manipulativeexperiments.

NRC (2000) further discusses the Cabled Systems envisioned, and highlights the re-use of retired commercial cablesystems:

Cabled seafloor observatories will use undersea telecommunications cables to supply power,communications, and command and control capabilities to scientific monitoring equipment at nodesalong the cabled system. Each node can support a range of devices that might include items such as anAutonomous Underwater Vehicle (AUV) docking station. Cabled systems will be the preferredapproach when power and data telemetry requirements of an observatory node are high. Earlygeneration commercial optical undersea cable systems that are soon to be retired will have thecommunications capacity to satisfy most anticipated observatory research needs, but will possibly haveinsufficient power capability. [note: see discussion of power in Table 2.] If these cables are suitablylocated for observatory research studies, their use could be explored to reduce the need for expensivenew cable systems.

As it is likely that cabled observatories would be installed at a site for a decade or more, substantialengineering development will be required in the design and packaging of the power conditioning,network management, and science experiment equipment. In order to meet the requirements for highsystem-operational time (versus downtime), low repair costs, and overall equipment lifetime,significant trade-offs will have to be considered between the use of commercially available andcustom-built equipment.

Two specific recommendations in NRC (2000) are particularly relevant:(2) A comprehensive seafloor observatory program should include both cabled and moored-buoy

systems…, and (5) A seafloor observatory program should include funding for three essentialelements: basic observatory infrastructure, development of new sensor and AUV technology, andscientific research using seafloor observatory data.

The NOPP (2001-2002) report An Integrated Ocean Observing System: A Strategy for Implementing the First Stepsof a U.S. Plan points to cables as one of the key platforms, including satellites, drifting and fixed buoys, autonomousvehicles and state-of-the-art ships, for collecting a variety of oceanographic data. Clark (2001) notes that, “Theprimary infrastructure of the OOI [Ocean Observatory Initiative] is a set of seafloor junction boxes connected to aseries of cables running along the seafloor to individual instruments or instrument clusters.”

The Scientific Cabled Observatories for Time Series (SCOTS) Committee was initiated by the National ScienceFoundation in April 2002 through the Dynamics of Earth and Ocean Systems (DEOS) Steering Committee toprovide advice regarding the planning and implementation of the NSF Ocean Observation Initiative (OOI). TheSCOTS Steering Committee’s primary focus was to elucidate the scientific questions that require, or would mosteffectively be addressed by, regional networks of multidisciplinary cabled observatories in three genericdomains—the open ocean, geologic plates, and coastal. Among the general observations of the SCOTS report(Glenn and Dickey, 2003), two points are directly relate to the use of cables:

1. Cabled Observatory Science: Scientists attending the workshop identified important scientificquestions within six science themes that could be addressed because of several attributes of cabledobservatories. In particular, the capability of cabled observatories to: (1) supply power sufficient forenergy demanding sensors and systems, (2) sample at high data rates for long periods, (3) collect alarge number of virtually continuous and diverse measurements over different spatial scales for



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unprecedented interdisciplinary coherence analyses, and (4) communicate the full datasets to shore inreal-time time enables new classes of scientific questions to be addressed.

4. Both New and Used Cables: It was determined that cabled observatories could be developedthrough initiation of completely new cabled systems and by taking advantage of abandoned cables thatwould be donated by the commercial sector. Both models have already proven successful and could bepursued for specific scientific problems and applications.

Among the recommendations of the SCOTS report:2. Retired Telecommunications Cables: There was widespread support for relocating retired

telecommunications cables to remote areas to complete the deep Earth imaging array. While this maybe one of the primary considerations for determining the new locations, once in place, the cable couldsupport a much wider variety of sensors and systems to facilitate ocean studies also desired by thefluids and life and the ecosystem working groups. It is recommended that current and future fundingmechanisms be used to ensure that retired cables deemed to be scientifically useful are adopted forcommunity use in a timely manner.

The National Science Foundation has already given approval to the University of Hawaii to re-focus the MRI fundedAloha Observatory Project for connecting the Hawaii Ocean Time Series (HOTS) site to HAW-4 fiber cable insteadof the previously proposed ANZCAN-D coaxial cable. New Zealand has expressed interest to NSF regardingpossible re-use of a section of TPC-3 re-deployed between the South Island of New Zealand and the Pacific-Antarctic Ridge. IRIS is working closely with the DEOS Cable Re-Use Committee in order to advise the scientificcommunity regarding these cable opportunities, and to seek guidance for the decisions that will need to be maderegarding which Cable Systems and spares the scientific community should acquire.

Cable System Characteristics. All of the first generation fiber systems are electro-optical systems that regeneratethe optical signals electronically in the repeaters. The systems are powered from the shore Cable Station, and operatein a constant current mode at 1.6 Amps. The Power Feed Equipment (PFE) is standardized for these systems, andtypically operates at about 5 kiloVolts (kV). Systems may be powered from one or both ends, depending upon thelength of cable. Each repeater draws power and there are losses in transmission due to resistance in the copper.Table 1 shows the power characteristics of the systems (derived with Mr. David Gunderson).

TABLE 1.

CableCable Station & Section with

AT&T Repeaters

SectionLength,

km

AverageRepeaterSpacing,

km

Numberof

Repeaters Amps

RepeaterVoltage

Drop

Copperloss,

Ohmsper km

VoltageDropper

Span

VoltageDrop per1000 km

HAW-4 Makaha, HI - Point Arena, CA 4263 71.0 60 1.6 22.3 0.7 78.0 1453

TPC-3 Makaha, HI 5265 69.9 76 1.6 22.3 0.7 77.1 1553

TPC-3 Tanguisson, Guam 1383 49.4 28 1.6 22.3 0.7 61.0 1448

GPT Tanguisson, Guam 2293 69.8 33 1.6 22.3 0.7 77.1 1430

TAT-8 Tuckerton, NJ 5880 67.0 88 1.6 22.3 0.7 74.8 1434

TAT-9 Manahawkin, NJ 4390 99.2 43 1.6 43 0.7 120.8 1439

TAT-10 Green Hill, RI 7197 131.1 55 1.6 43 0.7 145.8 1572

TAT-11 Manahawkin, NJ 3244 138.8 23 1.6 43 0.7 151.8 1439

The power available for a seafloor observatory depends upon the length of cable being powered, as the voltagelosses average about 1.5 V/km for all systems. Margin must be included for voltage variations due to the Earth’smagnetic field, which are typically 0.1 V/km (at high latitudes, 2-3 times greater). The PFE may be operated safelywith an additional load of 2.5 kV—up to about 7.5 kVolt total—permitting margin for additional power if required.Therefore, several kilowatts (kW) of power are potentially available for seafloor observatories connected to sectionsof these cable systems, with substantial margin, as noted in Table 2 for various cable lengths.



6

TABLE 2.

CableLength,

km

Transmission+ Repeater

Voltage Drop(average),

kV

PFEVoltage,

kV

AvailableVoltage for

Observatories Amps

PowerAvailable forObservatories,

kW

PFEVoltageMargin,

over 5 kV

AdditionalPower

Availablein Margin,

kW

Total PowerAvailable forObservatories,

kW

1,000 1.5 5 3.5 1.6 5.6 2.5 4 9.6

2,000 2.9 5 2.1 1.6 3.3 2.5 4 7.3

3,000 4.4 5 0.6 1.6 0.9 2.5 4 4.9

The Terminal Transmission Equipment (TTE) in the Cable Stations contains the optical transmit/receive equipmentthat provides the physical layer of the transmission. The SL260 and SL580 system TTE are of AT&T and Alcateldesign, respectively. The TTE works in conjunction with the Home Supervisory Unit (HSU) for fault location, forswitching spare lasers within repeaters and switching fiber spans between repeaters. Repeaters occur at 50-140 kmintervals along the systems, and electronically regenerate the optical signal. Because the repeaters already contain anelectronic interface with the systems, the repeater itself presents the one possible means to connect an oceanobservatory. The transmission protocol carries Plesiosynchronous Digital Hierarchy (PDH, plesio means near). Thetransmission speed is 295.6 Mb/s per fiber pair for SL280 systems and 591.2 Mb/s per fiber pair for SL560 systems,the transmission protocol being a simple multiple of the SL280. Table 3 shows the bandwidth for the systems.

TABLE 3.

Cable System Type

Bandwidth perFiber Pair,

Mb/s

FiberPairs +(spare)

SystemBandwidth,

Gb/s

HAW-4 SL280 295.6 2 (1) 0.6

TPC-3 SL280 295.6 2 (1) 0.6

GPT SL280 295.6 2 (1) 0.6

TAT-8 SL280 295.6 2 (1) 0.6

TAT-9 SL560 591.2 2 (1) 1.2

TAT-10 SL560 591.2 2 (1) 1.2

TAT-11 SL560 591.2 2 (1) 1.2

The systems were conservatively designed for an operational lifetime of 25 years. Given the extremely rigorousstandards imposed by AT&T, the equipment will probably be operational for additional decades. Earlier generationretired SD coaxial systems (Hawaii-2 and TPC-1) donated to IRIS Ocean Cable, Inc., after 25 years of telephoneservice have operated without problems for an additional decade. The nominal retirement date for these fibersystems installed 1988-1993 is 2013-2018. These systems are being retired early only because newer generationfiber systems using purely optical repeaters have up to 1,000 times the bandwidth, and therefore the older systemsare no longer commercially viable. The SL equipment is very robust, with internal redundant back-up systems. Areview of component failures with AT&T indicates only about a half-dozen, random individual laser failures overthe hundreds of repeaters over the lifetime of all 7 of these systems, and only two instances (TAT-8 and GPT) ofspan changes requiring use of the spare fiber link between two repeaters.

Because the cable equipment maintenance and storage facilities were sold by AT&T several years ago to TycoTelecommunications, the original system drawings and schematics of the cable repeaters and station plant are Tycoproperty. The Director of IRIS Ocean Cable met with Tyco on April 15 requesting the donation of these schematicsto IOC on behalf of the scientific community. Tyco has graciously agreed to provide all of the information that theyhave for the aforementioned systems. Working with Mr. Mark Tremblay, the schematics necessary for scientific re-use have already been transferred to IOC.

Ownership. A consortium of owners owns each of the cable systems, with AT&T being a large stakeholder. Someof the TAT cables have more than 40 European owners. The owners coordinate through a General Committee.Approval in principle for the scientific re-use of Hawaii-4/TPC-3 by AT&T and KDDI Japan has been given, and



7

Transfer/License Agreements have been have been drafted and submitted to IRIS Ocean Cable, Inc., by AT&T onbehalf of the GPT Owners. When the GPT Agreements are concluded, they will serve as a template for the transferof the other systems. For the Trans-Atlantic Systems, IOC is discussing ownership for the scientific community onlyof those Cables Systems (and sub-sections thereof) connected to AT&T Cable Stations. This decision is based upon1) Cable Station space availability, 2) equipment standards, 3) fishing/trawling problems at the European coast, and4) avoidance of foreign liability and environmental clean-up obligations. Discussions with the European Owners fortransfer of the TAT systems have not yet led to an agreement-in-principle, and there is expressed reluctance on theirpart due to concerns about future liability.

Cable Stations. There is available space in each of the AT&T Cable Stations. AT&T has no presence outside of theUS for these systems, and any arrangements with a foreign cable station must be with the respective overseestelecommunications company that operates the station. AT&T has offered to provide for license space for scientificuse, in much the same fashion as done for TPC-1 at the Guam Tanguisson Station and for Hawaii-2 at the HawaiiMakaha Station. This space is valuable. The current commercial rates for the fiber Cable Systems are of the order of$100-300K/yr. Current yearly cable station license costs for the scientific use of TPC-1 and Hawaii-2 are about$15K/yr/each, which are more than an order of magnitude lower than standard commercial rates. Space needs (andhence License costs) for the scientific equipment should in principle be less than commercial needs, as much of themultiplexing equipment is not required for scientific use. Scientific use of any of these Systems will likely takeseveral years. It may be possible to defer Cable Station costs, either by removal of equipment from the Stations, andby other arrangements with AT&T; these are being actively explored. However, it will be important to preserve theoption for use of the Cable Station.

The Manahawkin Cable station in New Jersey, which services only TAT-9 and TAT-11, is a unique case in that itmay be closed upon retirement. The station itself is located in a Fish and Wildlife Preserve, and the disposition ofthe land and station is still under discussion at AT&T. Upon introduction by IOC to AT&T during a visit toManahawkin in May, Rutgers University, which operates the nearby LEO-15 scientific cable, has entereddiscussions with AT&T about the possibility for donating this facility to them. Unless ownership issues regardingthe Manahawkin Cable Station can be successfully resolved within the context of the retirement of these CableSystems, the scientific use of the TAT-9 and TAT-11 systems remains unlikely.

Equipment Standardization. There is a high degree of standardization in the AT&T equipment, both for the terminaland repeaters, and within the two types of the first generation SL280 and SL560 equipment. There is universaljoining equipment for splices. However, the actual hardware installed by AT&T and their partners is not the same.The terminal equipment oversees is different from AT&T. More importantly, sections of repeaters changedepending upon who was responsibility for a section of the system. For instance, the TPC-3 system uses JapaneseKDDI repeaters west of the Branch, and AT&T repeaters eastward. Similarly, TAT-8 has AT&T repeaters fromNew Jersey to the Branch near UK and France, after which British and French repeaters respectively are used. TAT-9 and TAT-11 have AT&T repeaters only part way across the ocean. Significantly, AT&T repeaters cannot be

simply controlled and monitored byan overseas cable station, and viceversa (although the repeater willblindly retransmit the signal if it isthe correct format). HAW-4, GPT,and TAT-10 have only AT&Trepeaters. In order to work within theAT&T standard, this discussionfocuses only on the Cable Systemsand sections of Cable Systems, whichhave AT&T repeaters. In general,these include all cable sectionsconnected to AT&T Cable Stations.

Cable Burial and Fishing. AT&Tburies its cable to protect againstfishing and trawling activities. This isnot a problem in the Pacific, where

Figure 4. Map of TAT-10 from Green Hill, Rhode Island to Germany.



8

the water gets deep very quickly, but has been a significant problem in the Atlantic. Nearly all of the cable faultproblems in the Atlantic occur on the European side, where sufficient measures were not taken by the Europeanpartners to bury the cable in the shallow, near continental margin. This has created a continual problem in Europefrom fishing trawlers and cable chafing by currents at the seafloor. For AT&T the problem rate on the US side of theAtlantic has been only 1 fault per 5 years per 6 cable systems (1 fault per 30 cable-system-years). Even though thefault history is very good for AT&T systems, careful review of the actual history indicates that the only system withsuch problem is TAT-8 on the New Jersey shelf beyond the first repeater.

Liability and Environmental Clean-up Obligations. The IRIS Consortium formed IRIS Ocean Cable, Inc. (IOC) as a501(c)(3) not-for-profit corporation for cable ownership and license agreements for the acquisition of TPC-1 andHawaii-2 for science, and can provide a vehicle for the transfer of the fiber optic Cable Systems. The LicenseAgreements dictate operational requirements for having equipment in the Cable Station, which includes its removalupon termination of the License Agreement. There are liability issues in owning something on the seafloor (thecable itself). If a fishing trawler snags the cable and looses his net, traditionally AT&T paid them to replace the net.However, IOC has no assets but the Cables. Marine insurance will be obtained, but as noted the stronger step ofavoiding Cable Systems with a history of fishing related problems is a more conservative course.

The US has no law that requires AT&T to remove the cable from the shallow coastal region upon retirement.Recently New Jersey passed a law requiring removal of new cable systems from their coast, which does not affectthe older TAT systems. In accepting TPC-1 and Hawaii-2, IOC will not have to remove the cables once the systemsare retired from scientific use. However, IOC will have to remove equipment from its license space at the cablestations upon project completion. Similarly, a US scientific entity such as IOC would not have to remove a fiberoptic cable from the seafloor of the US coast after scientific retirement.

This is not the case for the European systems. When the four TAT Systems (8, 9, 10, and 11) are retired, the Ownerswill hire a cable ship to remove the cables from the European coast. If these sections of cables are donated toscience, then the scientific entity would in principle have to remove the cable after retirement from scientific use.This is a substantial obligation (perhaps prohibitive with typical scientific funding). Since the re-use of commercialcable systems or any new scientific cables on the coast of Europe faces similar restrictions, the European communitywill need to carefully evaluate the future implied costs for cable systems.

Similar asymmetry of law exists for cables landing in Japan versus the US. For TPC-1, IRIS entered into amemorandum with the University of Tokyo obligating the Japanese side to be responsible for Japanese coastal cleanup. A similar arrangement may be possible with TPC-3, if the Japanese scientific community decides to re-use thewestern portion of the system.

As NSF looks to laying its own coastal and regional cable systems (e.g., NEPTUNE) the fishing and liability issuesare part of the opportunity that must be considered.

Spares. AT&T is making available all of its spare cable and equipment for these systems. There are 23 SL560system repeaters and 15 SL280 system repeaters. There is nearly 700 km of fiber optic cable (5 cable types fromlightweight to double-armored), in 41 sections of 1 to 40 km length. There are also spare TTE, PFE, and repeaterelectronics at AT&T’s New Jersey warehouses. This can be an extraordinarily valuable resource for science. Newlightweight SL cable costs about $10/m or $10K/km. Lightweight cable can be used to link remote sites kilometersfrom a central hub. The sections of armored cable are essential for both shore access and exposed basalt seafloor.Each of the repeaters may be a potential node for ocean observatories. The first three pans of cable (82 km) andthree repeaters have already been transferred from AT&T to IOC from the retired GPT system.

The principal challenge presented in the donation of this spare cable and equipment is where to store it. BothUniversity of Hawaii (at Sand Island) and Rutgers University have offered some storage space for the spares.Because the AT&T storage facilities were sold several years ago to Tyco Telecommunications, the spare pans (21 ft.diameter) of cable and repeaters are currently stored at Tyco facilities at Guam, Honolulu, Portland, and Baltimore.Commercial storage rates for the spare cable available for single systems reach $20-150K/yr, depending uponstorage location and cable volume. As the Guam storage facility is planned to be closed by Tyco in September,shipping costs to move the GPT spares now owned by IOC to Honolulu is being coordinated with the University ofHawaii Project Aloha. Negotiations with Tyco are currently underway in consultation with NSF to arrange for the



9

storage of these spares at rates substantially below commercial storage rates. If funds are not available for storage,then the donation of much of the spare cable will have to be declined.

Acquisition Timeline. The approximate timeline for action in acquiring these Cable Systems for science is noted inTable 4. Upon retirement, there is about six-month period to clear all matters before the books are closed. Duringthis time the disposition of all cable station equipment, surplus cables and spare are concluded. Transfer of sparecable and repeaters must be arranged early. As there is no immediate need for space in the relevant cable stations,the actual transfer and licensing agreement can take place in six months or longer following the conclusion of anAgreement-in-Principle.

Because the European coastal portion of the TAT cables will be recovered and disposed (assuming no scientific re-use by the European science community), the final disposition of these systems will await retirement of TAT-9,when a cable ship will be hired the dispose of all systems at the same time.

IRIS is endeavoring to extend the timeframe for acquiring the Cable Systems in order to keep options open for thescientific community and NSF. However, commercial interests of the telecommunications companies will dictate theschedule.

Table 4.

Cable Retirement Date Decision on Spares Transfer Agreement-in-PrincipleTAT-8 May 2002 Spares lost November 2003

Station Equipment temporarilysaved at IOC request 11/2002

GPT April 10, 2003 June 1, 2003 October 1, 2003TAT-10 June 30, 2003 August 31, 2003 December 31, 2003TAT-11 June 30, 2003 August 31, 2003 December 31, 2003HAW-4 September 30, 2003 December 31, 2003 March 31, 2004TPC-3 September 30, 2003 December 31, 2003 March 31, 2004TAT-9 December 2003 February 2004 June 2004

Cable System Summary. The status of negotiations and discussions for these 3 Pacific and 4 Atlantic Cable Systemsunder discussion are briefly summarized. AT&T has submitted draft Transfer and License Agreements forconsideration.

Pacific CablesThe Cable Owners have agreed in principle to transfer the cables for science, subject to an acceptable TransferAgreement. There has been no fishing/trawling cable damage to any of these systems. IOC currently holds anAT&T license for space in the Guam Tanguisson Cable Station for TPC-1 and the Oahu Makaha Cable Stationfor Hawaii-2. These Cable Stations also serve GPT, TPC-3, and HAW-4. The University of Hawaii, whichcurrently stores a pan of Hawaii-2 cable at its Sand Island facility, has expressed interest in helping with cablestorage and is approaching Tyco regarding their local storage depot.

GPT. The entire system has AT&T repeaters. The American scientific interest in GPT is from Guam to thebranch unit at about 2400 km west. IOC has signed a Transfer Agreement for 3 pans of surplus fiber cable (82km) and 3 repeaters.

TPC-3. The US interest is the section west of Oahu to the Branch that uses AT&T repeaters. The Japanesescientific community is considering the western portion of the system. Significant spare cables and repeaters arelocated in Honolulu and Yokohama.

HAW-4. The entire system has AT&T repeaters. NSF has a funded proposal, Aloha Observatory, with aninterest in using this Cable System. Significant spare cables and repeaters are located in Honolulu and Portland.



10

Atlantic CablesAlthough AT&T has agreed in principle to transfer the cables for science, subject to an acceptable TransferAgreement, the European Owners have expressed reservations in transferring the cable systems to a not-for-profit scientific organization such as IOC due to liability concerns. Rutgers University, which operates theLEO-15 cable near the AT&T Tuckerton Cable Station has expressed an interest in the Atlantic Cables. Rutgershas offered to help coordinate with the Atlantic Cable Stations and provide some storage space for spare cablesystem equipment. The European terminations of all of the Atlantic Cable Systems have had significanttrawling/fishing problems and possess environmental requirements to remove cable from their coastal watersafter use.

TAT-8. The system has AT&T repeaters from the US to the branch, and reaches the Mid-Atlantic Ridge. Therehave been two fishing/trawling problems beyond the first repeater at about 50 km out. If only the short coastalsection of TAT-8 were used, the standard Cable Station Terminal equipment may not be needed (with perhapssignificant savings of space and concomitant License space cost). There is license space available in theTuckerton Cable Station.

TAT-9. The system has AT&T repeaters from the US to near the Mid-Atlantic Ridge. There is a record offishing/trawling problems on the Canadian coast. Only the section of the TAT-9 system from the US CableStation to the first branch and then to the Mid-Atlantic Ridge is being considered for scientific use by the US.The Manahawkin Cable Station in New Jersey may be closed after TAT-9 and TAT-11 retirement. Rutgers isexploring the possible re-use of the building, which could make possible the re-use of TAT-9. Significant sparecables and repeaters are located in Baltimore.

TAT-10. This Trans-Atlantic Cable could be used for a Mid-Atlantic Ridge observatory. The entire system hasAT&T repeaters. There is a record of fishing/trawling problems from the European coast to northwest ofIreland, but none on the US side. Only the section of the TAT-10 system from the US coast into deep waterbeyond the Mid-Atlantic Ridge is being considered for scientific use by the US. There is license space availablein the Green Hill, Rhode Island, Cable Station. However, there is a question whether this station may remainopen in the future when TAT-12 and TAT-13 retire. Significant spare cables and repeaters are located inBaltimore.

TAT-11. The system has AT&T repeaters from the US to the section southeast of Newfoundland. There hasbeen no record of fishing/trawling problems on the US side. The Manahawkin Cable Station in New Jersey maybe closed after TAT-9 and TAT-11 retirement. Rutgers is exploring the possible re-use of the building, whichcould make possible the re-use of TAT-11. Significant spare cables and repeaters are located in Baltimore.

Future Implementation for Science. This section looks beyond the acquisition of the Cable Systems toward using theSystems for science. Many of these concepts have been outlined and discussed in the various reports referenced inScientific Opportunities, and are mentioned here to provide context for these fiber optic Systems.

Scientific re-use of a fiber optic cable system changes its original use from a telephone system between two coasts toa system to provide telecommunications and power to the seafloor. There are a number of ways in which thesystems may be modified, depending upon the complexity of re-use. Detailed discussions have taken place with theAT&T/Tyco engineers who designed these Cable Systems and have been offering their assistance in the Cable re-use effort. These people, led by Mr. Mark Tremblay, bring both key expertise and extensive good-will contactsthroughout the AT&T and Tyco organizations. A group of 30 cable system engineers have been canvassed and haveexpressed interest in helping with engineering work in using the Cable Systems for science. Scientific re-use ofthese first generation systems is both technologically feasible and may be straightforward. Re-engineered sparerepeaters or other in-line nodes may used for an observatory system, and the kilometers of spare cable being offeredby AT&T may be used as branches off the trunk to remote instrumentation.

Two models have been followed in re-using coaxial submarine telephone cable systems. For TPC-1, aninstrumentation package was spliced into the cable, which remained connected to the cable stations on either end.For Hawaii-2, the original cable was cut in the middle and the Hawaii-2 Observatory (H2O) junction box wasattached to the section going to the Hawaii terminus. This approach permits easy repair, replacement, and additionsof sensors. The other section of the Hawaii-2 cable is effectively retired on the seafloor, unused. Furthermore, since



11

the repeaters on the unused section of cable are not powered, this power is available for scientific sensors. ForHawaii-2 this amounts to about 400 watts. Both of these models used space in the AT&T cable station for theterminal equipment. The sections of cable near the cable stations, which were originally buried by AT&T, were leftundisturbed.

The Hawaii-2 re-use model may be applied for the fiber optic systems. Cutting a cable system in the middle willyield about 4-9 kW power on the seafloor. Using loopback telemetry, the system bandwidth may be used from eithercable station. In this model a junction box installed at one end becomes a server to other junction boxes in a startopology (spokes from the center). These remote boxes would be connected by electro-optical cable to the server.Sensors would be added and modified at the junction boxes in the manner of the Hawaii-2 Observatory. The cablesystem is powered from the Cable Station, and the basic telemetry would be modified to carry IP traffic. With thelarge amount of available power on the seafloor, the junction boxes can also serve at docking stations forAutonomous Underwater Vehicles (AUVs), which can get power and upload/download data after service runs toremote instrumentation or other autonomous scientific surveys.

Following the example from TPC-1, nodes may be spliced into multiple points along the cable. This requirescutting, lifting, and splicing into the system. An installed node may serve both local instrumentation and additionaljunction boxes connected by cable. There are margins built into the repeaters for maintaining signal characteristics.One must be careful in splicing additional cable or sensors that these margins are strictly adhered to. The earlierSL280-series cable systems have closer repeater spacing, and effectively greater margins. Splicing into the middle ofa cable system is inherently risky. However, if one designs to minimize risk to the whole system, then one canpotentially install many scientific nodes along the re-used cable system. Installation of such nodes will require acable ship with splicing equipment.

H2O re-used the RF spectrum available in the coaxial cable, subdividing the bandwidth into channels connected tostandard modems. Care was taken to maintain the frequency and power standards that the repeaters were designedfor. Similar care is required for the fiber systems. The electro-optical repeaters operate at 1.6 Amps andcommunicate only at SL280 or SL50 data rates. Although the systems carry PDH traffic, appropriate terminalmodifications, complimented with corresponding node hardware, can enable the system to carry Ethernet traffic andstill permit control of the repeaters when necessary. Test circuitry built into the TTE and repeater loopbackcapabilities permit system testing on land within the Cable Station. The Seafloor Observatory nodes would then

distribute the signal via IP protocols.Using standard IP hardware minimizesdevelopment for the seafloor systemmirrored at the TTE in the Cable Station,while utilizing the highly reliableSL280/560 regenerators. There is awealth of available talent in the formerAT&T/Tyco engineers who designed andbuilt these Cable Systems, many ofwhom are actively interested (and somealready actively participating) in helpinguse these Cable Systems for science. Arecommended approach is to fund aworkshop inviting broad participation torecommend a design concept.

The Hawaii-2 system was used in place.One of the major new ideas for re-usingthese retired fiber optic systems is to re-locate them. One possibility, extendingthe prior example, is to cut the cable,then recover and re-lay the section at theend of one or both of the two pieces. Oneend of the cable remains connected to thecable station. For example, the Hawaii-4

Figure 5. Possible ideas for re-locating Pacific cables.



12

Cable can be divided, using one section off the coast of the US (as illustrated in Figure 5, or perhaps southward offof the Califonia coast) and the other end northwest or south of the current Hawaii-2 Observatory. GPT could berelocated to the region of the TAO/TRITON array of El Niño buoys in the tropical Pacific Ocean (shown in Figure5) or perhaps along the Marianas-Bonin active margin. TPC-3 could be wrapped around the Hawaiian Islands. Onecan move as much cable as available up to the point where the cable is overlain by a newer cable system. To getmore, the only recourse is to recover individual sections, leaving the overlying cable undisturbed, and then splicesections together. There are hundreds to thousands of km of cable that can be re-located without disturbingoverlying cable. However, in moving cable systems, close coordination with other cable owners may be necessary,if one plans to go across their cable on the seafloor.

Extending this model further, one can potentially pick up thousands of km of cable and re-lay it entirely in a newlocation. For instance, New Zealand has already expressed interest to NSF in collaborating on moving a section ofTPC-3 to the South Pacific, connecting a ridge observatory on the Pacific-Antarctic Ridge to Christchurch on theSouth Island, NZ. The longest open section on TPC-3 is about 5,000 km near Oahu to the branch point. There aremany such opportunities that can be conceived. In this model, one must provide for a cable station, arrange forpermitting to cross the beach, and bury the cable in the shallow coastal region. To do this would require splicingrecovered fiber sections with armored cable (available as AT&T spares) at the coast. To develop this project, closecollaboration is necessary with the country where the cable station would be provided.

Available AT&T spare cable can be used outright without the necessity of picking it up from the seafloor. Thesesections can be used as coastal segments or spokes from seafloor nodes. For example, the Bermuda Atlantic Time-series Study (BATS) at Hydrostation “S” just 15 nautical miles from Bermuda has been monitored since 1954.There is available spare cable in the Baltimore depot that could be used to link this site to Bermuda; and since thelength is relatively short, no repeater would be required.

AT&T and Tyco have indicated it is very feasible to pick up and re-lay fiber cable. However, it would be verydifficult to re-locate buried sections of cable. Hence, this section focuses on unburied sections of cable. A cable shipcan easily pick up a thousand km of cable, and a larger ship can pick up 3-4,000 km of cable. At the height of thetelecommunications boom when cable ships were at a premium and busy laying cable, the going rate was about$100K/day. The current rate for a cable ship is now about $20K/day. Under average conditions, cable can berecovered at 1-1.5 knots, and best-case conditions at 3 knots (worst case can be as slow as 0.1 knots) Hence underaverage conditions, 1,000 km of cable can be recovered at about $900K for a $40K/day cable ship. It can be re-layedat about 5-6 knots, for about $180K. Thus the cable relocation cost, not including transit, for the average case isabout $1.1M per 1,000 km. This cable cost may be compared to the cost of new fiber optic cable on a reel in awarehouse at about $10/m, or $10M for 1,000 km—this new cable cost does not take into account the additional costof the required repeaters. These costs do not include transit costs to bring the ship to the site, or to move the cable toa new site. Assuming a speed of 12 knots, the cable ship transit cost is about $75K per 1,000 km. There would alsobe additional costs for site surveys, time on site for splicing, etc., but this provides an illustration for re-laying cable.

Conclusion. The successful scientific use of retired telephone cables for seafloor observatories has beendemonstrated for TPC-1 (Kasahara et al. 1998) and Hawaii-2 (Butler et al., 2000), where the Hawaii-2 Observatory(H2O) between Hawaii and California on the seafloor at 5,000 m depth has provided over 99% data availability forthe Global Seismographic Network since October 1999. The coaxial SD Systems have provided both dependablepower and telemetry. The scientific potential has spawned new NSF-funded geomagnetic and biologicalinstrumentation for the H2O site, and an ODP borehole. The newly retiring, first-generation fiber-optic cablessystems offer 10 times more power, and nearly 1000 times more telemetry bandwidth than the coaxial systems,TPC-1 and Hawaii-2. The new opportunities that these fiber-optic cable systems now present for science are limitedonly by our imagination.

Acknowledgments. This paper has benefited substantially from discussions with Jeff Ewald, Mark Tremblay, DavidGunderson, Fred Duennebier, Tom Wills, J. Eric Stein, James Coble, Elin Hagadorn, Louise Ferrara, Jim Murray,Jodi Liska, Len Weitz, David Matsushima, Bill Marra, Catherine Creese, Bruce Wier, and Wade Higa. Supported byNSF Cooperative Agreement EAR-0004370.



13

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Butler, R., A. D. Chave, F. K. Duennebier, D. R. Yoerger, R. Petitt, D. Harris, F. B. Wooding, A. D. Bowen, J.Bailey, J. Jolly, E. Hobart, J. A. Hildebrand, A. H. Dodeman. 2000. Hawaii–2 Observatory pioneers opportunitiesfor remote instrumentation in ocean studies, EOS Trans. AGU, 81, 157, 162–163.

Clark, H. L. 2001. New seafloor observatory networks in support of ocean science research, IEEE ConferencePublishing, http://www.coreocean.org/Dev2Go.web?id=232087&rnd=5340.

Glenn, S.M. and T.D. Dickey, eds., 2003. SCOTS: Scientific Cabled Observatories for Time Series, NSF OceanObservatories Initiative Workshop Report, Portsmouth, VA., 80 pp., www.geoprose.com/projects/scots_rpt.html.

Kasahara, J., H. Utada, T. Sato, and H. Kinoshita. 1998. Submarine cable OBS using a retired submarinetelecommunication cable: GeO-TOC program, Phys. Earth Planet. Int., 108, 113-127.

National Ocean Partnership Program. 2001-2002. An Integrated Ocean Observing System: A Strategy forImplementing the First Steps of a U.S. Planhttp://www.coreocean.org/deos/Dev2Go.web?id=220672&rnd=16827.

National Research Council. 1998. Opportunities in Ocean Sciences: Challenges on the Horizon. National AcademyPress, Washington DC.

National Reseach Council. 2000. Iluminating the Hidden Planet, the Future of Seafloor Observatory Science.National Academy Press, Washington DC.

Appendix D.

Executive Summary: SL 280/560 Cable Systems Reuse Experts Workshop Report

Workshop Participants

Experts Workshop on Sl 280/560 Cable Re-Use for Observatories page 1 of 56

SL 280/560 Cable Systems Reuse Experts Workshop Report

Rutgers UniversitySeptember 29-30, 2003

Report Date: November 8, 2003

Executive Summary

PURPOSE: There is currently an opportunity to acquire and use retiring fiber optic submarinetelecommunications cable systems to provide infrastructure for ocean observing systems. The cablesystems, with an original capital investment of over $2B, are being retired well before their designlifetime because of conditions in the industry. Economics require the disposal of these systems asquickly as possible after they are retired, thus the academic community must decide quicklywhether these assets can and should be acquired. The purpose of this workshop was to obtain theadvice of experts with experience in the design and operation of the SL 280/560 cable systemsconcerning the feasibility and possible methods of using these cable systems to provide power anddata infrastructure for observatory networks.

FINDINGS:1) There appears to be no significant technical roadblocks in re-use of the cable systems for

ocean observatory arrays.2) While the three primary objectives in the implementation of submarine

telecommunications systems are reliability, reliability, and reliability, the re-use of thesesystems for scientific observatories must also allow for considerable flexibility, and theability to add and upgrade hardware on the ocean floor. This fact will likely degrade thetotal system reliability, but that decrease is a necessary consequence of the intended use.

3) Repeaters in these systems require that the cable provide a constant current of 1.6 A DC.The PFE (Power Feed Equipment) can supply voltages up to 7.5 kV. If both ends of thecable are powered, two PFEs are used an 15 kV is available to the system. Observatorypower systems would be series loads that drop the voltage at each observatory node andprovide a voltage source to observatory electronics. A similar supply is currently in useat the Hawaii-2 Observatory.

4) The observatory power supply must convert the constant-current cable power to aconstant-voltage power system suitable for electronic systems with variable loads andnegative impedance switching power supplies.

5) At least two data telemetry choices are available. Both will require development of achip set, and the advantages of one over the other have yet to be determined.

6) It is important to preserve the current station hardware and protocols that allow controlof the repeaters and identification of cable faults.

7) Wet-mateable electrical and optical connectors at observatory nodes are a criticaltechnology for ocean observatories. These connectors provide the flexibility demandedof a research observatory, but they also represent potential failure points. Theengineering community is reluctant to embrace the use of these connectors in criticallocations unless high reliability can be firmly established.


8) Acquisition of spares and cable system hardware are important steps in use of thesesystems for ocean observatories. Re-manufacture of equipment now available for onlystorage cost would likely be prohibitively expensive.

9) It should be possible to install a prototype observatory node on a retired optical cablewithin two years.

10) A work force of highly qualified engineers to perform the design and specificationsfunctions for the necessary equipment to utilize these cable systems for observatorynetworks exists in New Jersey.

9) While funding for construction of an observatory at Station ALOHA connected to theHAW-4 cable has been awarded, it will not cover the expense of design and constructionof critical equipment necessary for use of retired optical systems. Careful design of thesecomponents will make it possible to install observatories not only at Station ALOHA,but at numerous other locations.

RECOMMENDATIONS:1) We recommend that all useful hardware and spares available (as determined by industry

experts familiar with the re-use possibilities and available funds) be protected fromdisposal. Initial steps have already been taken in this area.

2) We recommend that a design and construction effort for critical sub-systems necessaryfor re-use as observatories be begun as soon as possible.

3) We recommend that the highly qualified engineering work force available in New Jerseybe utilized for the design and specification of the necessary equipment that will make itpossible to re-use all of the retiring systems for scientific observatories.


ATTENDEES:

* former AT&T/TYCO Engineer1 University of Hawaii2 TYCO Telecommunications3 IRIS4 Rutgers University

This workshop was funded by the National Science Foundation through grant OCE02-16164for development of a cabled observatory north of Oahu, and by the Incorporated Research Institutesfor Seismology for basic cable observatory infrastructure development under CooperativeAgreement EAR-0004370.

Name Expertise email

Fred Duennebier1observatory development,seismology, instrumentation [email protected]

David Harris1EE, power, instrumentation,observatory design

[email protected]

Mike Bruning* power, mechanical design [email protected] Calvo* power, high speed circuit design [email protected] Sipress* project management [email protected] Ehrenberg* regenerators, FPGA [email protected] Feggeler* systems, specs, tests [email protected]

Maurice Kordahi2cable, repeaters, couplings, ships,plows [email protected]

Roy Samras* cable jointing, mechanical R&D [email protected] Butler3 science, management [email protected]

Mike Perry*mechanical design, repeater &terminals [email protected]

Oscar Schofield4 university professor [email protected] Glenn4 ocean observing [email protected] Sirocky* power & electronic PKG [email protected] R. Gunderson* power, system design [email protected] D. Tremblay* terminal & transmission [email protected]

Robert L. Treadway*terminal & data networkcommunications [email protected]

John Risko* system, regeneration [email protected] Creese2 marine ops [email protected] Schesser* Systems design & SCOUT maint [email protected] Duennebier recording [email protected]

Appendix E.

Executive Summary: DEOS Cable Re-Use Committee Report

Committee Membership

DEOS Cable Re-Use Committee ReportExecutive SummaryInterest in fixed ocean observing systems has been increasing for many years as it becomesapparent that the technology is now available to collect and return large volumes of data to shoreusing satellite or cable technology. Cable technology is particularly appealing since orders ofmagnitude more bandwidth can be supplied to observatories continuously at relatively lowoperational cost relative to satellite links.

Due to rapid technology advances and a downturn in the industry, first and second generationlightwave submarine telecommunications cable systems are now being retired. These providedata capacities of 560 and 1120 Mb/s, respectively, and span long oceanic distances, includingboth transatlantic and transpacific. There is currently much discussion within the scientificcommunity about the potential scientific resource provided by the re-use of these cables forseafloor and water column research.

A DEOS Cable Re-Use Committee was tasked to provide the National Science Foundation andthe Scientific Community with advice on the many technical and economic issues that must beaddressed before significant resources are committed to the acquisition and re-use of retiredtelecommunications cable systems for scientific purposes. The specific issues that the committeewas asked to address are given in the scope, which is provided in Appendix 1 of this report, andinclude those related to engineering limitations, development, power, communications,relocation, liability and spares.

The principle findings of this study are:

- There are no fundamental engineering limitations that would prevent effective re-use ofretired cables either in-situ or relocated. The system power available for the observatory nodeinstruments will be a limiting factor but only when high power consuming instruments such aspumps are used in a long or multi-node observatory. The system data transmission capacityavailable for the observatory node instruments should not be a limiting factor. The only requireddevelopment that is unique to the re-use of retired systems is for circuitry to interface theobservatory node instruments to the cable data stream and for shore based circuitry to interfacethe IP data format to the cable data stream format.

- The only significant technical issues related to the relocation of cable are that cablerecovery at cross-under with other cables is not possible and recovery of buried cable should notbe assumed. There are no significant technical issues related to re-use of cable stations.

- For equivalent architecture and complexity, re-used cable systems either in-situ orrelocated, are almost always less expensive than new cable systems but it is deemed outside ofthe scope of the committee to comment on the issue of “equivalent architecture and complexity”.

The principle recommendations from the committee are:

- All spare cable and repeaters and available associated hardware and equipment shouldbe procured. All spare terminal electronics and all available test and maintenance equipmentshould be procured unless time is available to do sufficient system design for re-used systems topermit detailed decisions. A complete set of first and second generation lightwave submarinetelecommunications cable systems documentation should be procured.

- Less expensive cable storage capabilities should be developed, e.g. coastal river barges,inexpensive university and government facility, laboratory or Navy, waterfront space.

- A careful examination should be made of all terms and conditions in all of the existinglicenses and permits granted to the original cable system owners as well as all applicable lawsand treaties.

- Third person liability costs and indemnification should be evaluated with an insurancecarrier.

- Working groups should be established to- build upon the work started by IRIS Ocean Cable with respect to the re-use of

retired and to be retired cable systems,- develop a capital and expense investment time line to protect the ability to re-

use retired and to be retired cable systems until decisions can be made and- develop specific plans for cable re-use for input to the re-use decisions.

DEOS Cable Re-Use Committee Report page 30 of 3009/15/03

8.7. Appendix 7 – Committee Membership and AcknowledgmentsThe committee members are:

• Dr. Jack Sipress, Chair, AT&T (Retired), Tyco (Retired)• Dr. Fred Duennebier, University of Hawaii• Dr. Robert Gleason, AT&T (Retired), Tyco (Retired)• Mr. Gene Massion, Monterey Bay Aquarium Research Institute• Dr. Peter Mikhalevsky, Science Applications International Corporation

This report was sponsored by the National Science Foundation. Committee support wasprovided by Dr. William Fornes of the Consortium for Oceanographic Research and Education.This committee builds on work done previously by NRC committees, the SCOTS Committee,the DEOS Steering Committee, and by several individuals, particularly Rhett Butler (IRIS), N.Rondorf (SAIC), and Mark Tremblay (Tyco, retired). The committee would also like toacknowledge the contributions of Robert Boone, Jr. (AT&T, retired), Tien Nguyen (Tyco,retired) and William Sirocky (Tyco, retired). Their research and efforts and willingness to sharetheir ideas and information have made our task far easier.

Appendix F.

DEOS Committee Recommendations for Cable Re-Use

DEOS Committee Recommendations for Cable Re-Use5 October 2003

The DEOS Cable Re-Use Committee Report provided important recommendations for cable re-use.In particular:

• There are no fundamental engineering limitations that would prevent effective re-use ofretired cables either in-situ or relocated.

• The only significant technical issues related to the relocation of cable are that recovery atcrossovers is not possible and recovery of buried cable is not likely to be useful.

• For equivalent architecture and complexity, re-used cable systems are almost always lessexpensive than new cables.

• All spare cable and repeaters and available associated hardware and equipment should beprocured.

• Less expensive cable storage capabilities should be developed.• A careful examination should be made of all terms and conditions in all of the existing

licenses and permits granted to the original cable system owners.• Third party liability costs and indemnification should be evaluated with an insurance carrier.• Working groups should be appointed to pursue specific issues.

Upcoming cable retirements included TAT-8, 9, 10, 11 in the Atlantic and GPT, HAW-4 and TPC-3in the Pacific.

Alan Chave provided DEOS with questions about the cable re-use report. In particular, he raisedissues about:

• Constant current power• Communications• Network timing• Subsystem monitoring• Reliability• Non-Recurring Engineering Costs

DEOS felt the questions raised by Alan had real merit and was particularly concerned about the useof constant current power, especially in a multi-node environment and the potential for substantialnon-recurring engineering costs. The DEOS committee did not feel that it had the expertise to judgethe accuracy of the costs estimates provided by either the re-use committee report or those providedby Chave. Both engineering costs, as well as liability costs, are poorly known and impossible toquantify at this stage. However, the DEOS committee did feel competent to judge the scientificutility of the proposed cables.

The DEOS Committee split into two groups roughly characterized as global/regional andcoastal/regional to consider scientific priorities that might be considered for re-using existingcables. The committees were asked to not consider economic or technical issues in theirprioritization of scientific objectives.

The Global/Regional Committee recommended priorities in the Atlantic and Pacific. In the Atlantic,the priorities, in order, were:

• TAT-10• TAT-9• TAT-11

TAT-10 provides a potential for measuring transports through the Iceland-Faeroe gap andinvestigating the dynamics and mixing of water masses flowing equator-ward through the gap. Thisis a high-priority Timeseries site and has been included in much of the DEOS planning. TAT-9 andpossibly TAT-11 could potentially be used for instrumenting the high priority seismic site at 23°Non the MAR – this site has also been included in DEOS planning. All three of the sites involvepicking up cable and moving the end to a different location while keeping the shore station, in theUS, intact. The move for TAT-10 is relatively short although it would be necessary to provide multi-node (at least two) connectivity on the cable spanning the gap. TAT9/10 is potentially a single-nodeinstallation, but at least 2000km of cable will need to be moved. In addition, armored cable maywell have to be installed on the distant end of the cable on the Mid-Atlantic Ridge. The PacificPriorities were:

• TPC-4• GPT• TPC-3

While TPC-4 is not yet available, this is the highest priority site for DEOS; it could potentially beused as a single node mode or in a multimode configuration. The site could be used to supportStation P in the North Pacific – a high priority site for climate and seismology (single node). GPTcould provide an opportunity for making low latitude western boundary current measurements andexamining tropical-extratropical links. TPC-3 is not specifically a DEOS priority, but it will providea means for making continuous measurements from the Aloha site.

The coastal/regional committee took a somewhat different tack. They made three points:

• There is compelling science that could be done with cable re-use in both the Atlantic andPacific

• The CoOP and SCOTS reports provide important science drivers for TAT- 9, 10, and 11, aswell as HAW-4 and TPC-4. Of these cables, TAT-11 had highest priority because of theopportunity for multiple-node measurements extending along the northeast US coastline.

• Further efforts should be undertaken to prioritize the sites and pick one for a pilot study.

Generally, the DEOS Committee was unwilling to provide approval for pursuing ownership of anyof the cables currently available or available in the near future. Given ambiguity in costs and thequestions raised about technical feasibility, it is not possible to recommend the expenditure of avague level of funding for this purpose. The DEOS Committee made several recommendations:

• Ask that the Cable Re-use Committee respond to the comments on their report by AlanChave.

• Conduct an engineering design desktop study, under contract, to develop further the costsfor cable re-use. In particular, consider the use of TAT-11 in a multi-node environmentalong the northeast US coast to Newfoundland and the use of TPC-4 for servicing Station Pin the north Pacific. This study must include liability and ownership costs in addition toneeded non-recurring engineering costs. These costs must be traded off against the cost ofthe use of new cable especially designed for the purpose and the use of buoys for makingthe DEOS measurements. DEOS anticipates this study will cost on the order of $200K.

• Consider the acquisition of spare cable for use in functions such as “extension cords” forseafloor nodes at either cabled observatories or global buoy installations. However, theacquisition, moving and storage of the cable should not exceed an annual cost of $200K.There was no interest in acquisition of other spares.

The DEOS committee is fundamentally concerned about the investment of significant resources onlegacy systems in extending oceanographic measurements into the future, especially at sites that are

not of highest priority for time series measurements. Key to funding of MRE-FC’s is the intent toexploit new and emerging technologies in making unprecedented measurements in the oceans. It isacknowledged that cabled observatories have great potential, but the DEOS committee has not yetbeen presented with well-planned (technically and scientifically) proposals to re-use existing cablesto address high priority science. Thus, it was judged to be premature to recommend for or againstcable re-use.

This reports on the priorities for the DEOS project. The use of existing cables by other scientificinterests may well have priorities quite distinct from those expressed in this report.

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