3

ARCTIC RESEARCH PLATFORMS

Research in the Arctic Ocean is supported at the present time by a variety of platforms such as icebreakers, ice-strengthened ships, long-term and short-term ice stations, autonomous instrumentation, aircraft, submarines, and satellites. Scientific uses of these platforms were discussed in Chapter 2.

Each research platform has advantages and disadvantages associated with access to the research area, properties that can be measured, spatial and temporal sampling capabilities, and cost. For any given scientific purpose, one platform may be clearly superior. For instance, if the discussion is limited to proven measurement systems, satellites are best for measuring the extent of sea ice throughout the entire Arctic on time scales of days to decades. Autonomous ice buoys are best for measuring the synoptic patterns of surface air pressure and winds on similar time scales. Acoustic methods provide the best means for synoptic time-series measurements of properties that affect sound speed (temperature and salinity). Submarines are best for rapidly covering the entire ocean basin, for measuring the large-scale volume and morphology of sea ice throughout the basin, and for acoustic and gravity surveys. Ice camps allow long timeseries drifting measurements, while field camps on land allow long-term studies in particular coastal locations. A research icebreaker provides the best opportunity for carrying large scientific parties and instrumentation to specific locations for sampling or experimentation and for interdisciplinary studies. Certain tasks, such as large-scale horizontal towing (possible in some ice conditions), large-scale coring of shallow sediments, and processing of large volumes of seawater and biota, require a research icebreaker.

U.S. investigators have conducted scientific measurement programs from a variety of platforms in the Arctic Ocean and its marginal and adjacent seas,



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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS 3 ARCTIC RESEARCH PLATFORMS Research in the Arctic Ocean is supported at the present time by a variety of platforms such as icebreakers, ice-strengthened ships, long-term and short-term ice stations, autonomous instrumentation, aircraft, submarines, and satellites. Scientific uses of these platforms were discussed in Chapter 2. Each research platform has advantages and disadvantages associated with access to the research area, properties that can be measured, spatial and temporal sampling capabilities, and cost. For any given scientific purpose, one platform may be clearly superior. For instance, if the discussion is limited to proven measurement systems, satellites are best for measuring the extent of sea ice throughout the entire Arctic on time scales of days to decades. Autonomous ice buoys are best for measuring the synoptic patterns of surface air pressure and winds on similar time scales. Acoustic methods provide the best means for synoptic time-series measurements of properties that affect sound speed (temperature and salinity). Submarines are best for rapidly covering the entire ocean basin, for measuring the large-scale volume and morphology of sea ice throughout the basin, and for acoustic and gravity surveys. Ice camps allow long timeseries drifting measurements, while field camps on land allow long-term studies in particular coastal locations. A research icebreaker provides the best opportunity for carrying large scientific parties and instrumentation to specific locations for sampling or experimentation and for interdisciplinary studies. Certain tasks, such as large-scale horizontal towing (possible in some ice conditions), large-scale coring of shallow sediments, and processing of large volumes of seawater and biota, require a research icebreaker. U.S. investigators have conducted scientific measurement programs from a variety of platforms in the Arctic Ocean and its marginal and adjacent seas,

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS including the Polar-class icebreakers of the U.S. Coast Guard, the research vessel (R/V) Alpha Helix supported by the National Science Foundation (NSF), U.S. Navy nuclear-powered submarines (SSNs), and non-U.S. icebreakers. In addition, there is a growing body of U.S. experience acquired in the ice-covered seas surrounding Antarctica aboard the icebreaker R/V Nathaniel B. Palmer. Strategies to achieve an efficient, effective fleet of U.S. vessels that support oceangoing research in the Arctic are best developed in light of recent experience on these vessels. U.S. Icebreakers A research vessel capable of icebreaking is uniquely qualified as a moveable laboratory that can transport scientists and equipment to polar regions; enable direct observations and in situ experiments in polar regions; sample and process large volumes of water, sediments, flora, and fauna; take vertical profiles of the water column in several locations within a limited time period; and collect biological samples of pelagic and benthic organisms. It can provide good spatial coverage of all arctic regions, including shelf, slope, and central ocean basin (ranked in order of increasing difficulty), given appropriate ice conditions and support ships. A surface icebreaker is also necessary for coring and dredging the sediments and rocks of the seafloor, although limited capabilities for these operations might be expected from an ice camp. The USCG Cutters Polar Sea and Polar Star are the only U.S. icebreaking ships that can carry researchers into the central arctic ice, under some conditions. These Polar-class icebreakers were built in 1976 and 1978, respectively. They were not designed for oceanographic research, but during the past 10 years, the U.S. Coast Guard has made modifications and added equipment to provide limited oceanographic research capabilities for these vessels. These improvements include provision of 1,200 square feet of laboratory space, installation of hydrographic and trawl winches, and clearing an area on the main deck aft for over-the-side work and towing. Recently a number of scientific expeditions using these ships have been carried out successfully, although there are also examples, such as the Arctic 91 expedition, of cruises that failed because of engine maintenance problems on these vessels. The projected scientific capabilities of the Healy (being built for the U.S. Coast Guard) and the proposed Arctic Research Vessel (ARV) (conceived and designed with financial support from the National Science Foundation, Division of Ocean Sciences) are patterned after those of the most recent class of Navy research vessels, the AGOR-23 to 26, except for additional capabilities required for studies in an ice-covered ocean. Each ship has the same types of laboratories and roughly the same amount of open deck space and space for scientific supplies, but the ARV has approximately 1.5 times the laboratory space of the

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS Healy. The laboratory space could become roughly equivalent if the size of the crew on the Healy is reduced to that of the number on a civilian research vessel. The major characteristics and scientific capabilities are summarized and compared with those of the Polar-class icebreakers and the Palmer in Table 6a and Table 6b. A multibeam bottom-mapping sonar has recently been added to the Healy's planned complement of scientific equipment. Table 7 summarizes the American Bureau of Shipping (ABS) ice classification scheme. Although the Polar-class icebreakers (ABS class A5) were constructed to be able to work alone in the central Arctic Ocean, their science capabilities are less than those of the Healy or the ARV, and only the Russian nuclear icebreakers can operate without an escort in this area under all conditions. The Healy (roughly equivalent or slightly superior to an ABS class A3 in capabilities) and the proposed ARV (ABS class A3) are being designed to support science operations and have significant icebreaking capability, estimated at 4 to 4.5 feet of ice thickness at a speed of 3 knots. However, neither ship will be capable of navigating independently in most multiyear ice. Consequently, both ships would have to be escorted by a larger, more capable ship, such as one of the Polar-class vessels or a nuclear icebreaker, to work safely in the central Arctic Ocean. TABLE 6a Comparison of Icebreaker Specifications   ARV Healy Palmer Polar Class Displacement (LTWS) 11,500 16,300 6,800 13,400 Length (feet) 340 420 308 399 Beam (feet) 76 82 60 84 Endurance (days) 90 65 75 60 Power (BHP) 18,000 30,000+ 13,200 18,000-75000 Ice capability (3 knots) 4 feet 4.5 feet 3 feet 6 feet ABS ice class A3 A3-A4 A2 A5 Crew 26 75a 26 152a Launch date [2000] 1998 1992 1976/78 aIncludes aviation detachment.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS TABLE 6b Comparison of Icebreaker Science Capabilities   ARV Healy Palmer Polar Class Science complement 36 35/50 37 35 Total lab space (sq ft) 7,900 3,800 6,800 1,200 Working deck space (sq ft) 13,300 3,000 4,800 Small Scientific storage (cu ft) 27,600 20,000 10,000 Unknown Vans 4/11a 8 4/8a 7 Helicopter Visit only 2 2 possible 2 Full complement of winches yes yes yes no Annual operating cost ($M)b 9.1 11.3c 10.7 11.5c a These values indicate: vans with direct interior access/total number of vans. b These values do not include amortization of construction costs. c Actual cost is shown. The cost to the NSF Arctic Science Program is smaller, because USCG partially subsidizes the cost (see Table 10). Based on the letters and reports made available to the committee, the arctic research community would prefer to use the proposed ARV, instead of the USCG vessels, because of the incompatibility of USCG missions with the needs of efficient scientific research. The primary missions of the U.S. Coast Guard include maritime law enforcement, safety of life at sea, search and rescue, and maintaining ports ice-free, although the committee was informed that the Healy's primary mission will be science. Consequently, USCG vessels carry larger crews than are required for purely scientific missions; based on the experiences of the scientific community with Polar-class vessels (whose stated missions are not primarily science), scientific cruises can be interrupted when they conflict with other USCG missions. Also, because of frequent personnel rotation, it is difficult to establish and maintain the requisite expertise among officers and enlisted personnel for scientific work in the ice-covered ocean. (Although

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS USCG crews lack expertise in scientific research, they are experienced in handling ships in ice.) The Arctic Research Consortium of the United States (ARCUS), at its October 1994 meeting, strongly supported management of the ARV as a part of the University-National Oceanographic Laboratories System (UNOLS) fleet. The ARV would operate with a crew of 26, whereas the U.S. Coast Guard envisions a crew of 75 for the Healy. The turnover of crew and technical support staff would be far less on the ARV than the Healy, because the only mission of the ARV would be science. The experience of the academic community is that the continuity, maturity, and experience of the support staff are particularly important for the maintenance of sophisticated instrumentation and equipment and to ensure a high likelihood of success on scientific cruises. This is especially important in the harsh arctic environment. TABLE 7 American Bureau of Shipping (ABS) Classification Scheme for Icebreakers and Ice-Strengthened Vessels ICEBREAKER       ABS ice class Ice transit, continuous at 3 knots (ft) Ice transit, back and ram (ft) Example of ship in fleet (or proposed) A5 6 20 USCGC Polar Sea A4 4.5 8 Louis St. Laurent A3 4 7 Proposed ARV, USCGC Healy A2 3 5 R/V Nathaniel B. Palmer ICE-STRENGTHENED       C thin, 1st year open pack ice   R/V Alpha Helix Certain design features of the ARV (Kristensen et al., 1994) offer superior performance for research in an ice-covered ocean. The advanced hull design should result in superior maneuverability in ice; that is, smaller turning radius,

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS better backing capability in ice under compression, and controlled heeling of the vessel. Based on scale-model basin tests (Kristensen et al., 1994), the advanced hull design of the ARV should provide icebreaking capability nearly equal to that of the Healy with two-thirds the horsepower and fuel consumption. However, the hull design of the ARV is not optimal for open-water performance, making the ARV poorly suited for alternating service in the arctic and antarctic regions. The special hull design of the ARV should clear most of the ice to the side and provide a nearly ice-free channel behind the ship, making horizontal tows possible. The ARV's deep screws will result in less milling of ice. The provision of a forward Baltic room on the port side of the ship will allow parties to disembark onto the ice from a sheltered staging area, while work that requires open water alongside (e.g., CTDs, coring, ROVs) can be carried out from the starboard side. The greater endurance of the ARV compared with other vessels will prove more economical because refueling ports are distant from the Arctic Ocean, and the ability to carry out two or three major cruises without refueling will be a distinct advantage. However, like the Healy, the ARV will need the escort of heavier-duty icebreakers to remain safe when penetrating seas covered with multiyear ice buildup. Experiences of Scientists on Recent Icebreaker Cruises USCG Icebreakers—USCG icebreakers have provided support for research in both the Arctic and the Antarctic for many years. There is no question that the data acquired on these cruises have made valuable contributions to a variety of scientific disciplines. The Polar-class icebreakers, however, as military vessels, serve a variety of purposes. In contrast to the research fleet operated by UNOLS and non-U.S. research icebreakers such as the Oden and the Polarstern, the support of scientific research is not the sole mission of USCG vessels, and in some cases is not the primary mission. When science support is not the top priority, research efficiency decreases. Therefore, it is not surprising that problems are identified when scientists, accustomed to working aboard UNOLS vessels dedicated to science, evaluate the amount and quality of research support provided during cruises on USCG icebreakers. The problems cited are due mainly to the limited science capabilities available on the Polar-class vessels and the mode of operation and manning of these vessels. Through the 1980s there was growing concern that the shipborne data needed to address important scientific problems could not be obtained by U.S. scientists aboard USCG icebreakers operating as they had in the past. These concerns, and the underlying problems, were summarized in a 1988 report of the NRC Polar Research Board (PRB) (NRC, 1988). The PRB circulated a

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS questionnaire to scientists who had participated in USCG cruises. The report, based on 45 responses, cites the following common problems: Ship's management and chain of command on the USCG vessels produce an operating environment that is slow, inflexible, and unresponsive to scientific needs; important deck equipment is outdated, inoperative, or nonexistent; and there is too little laboratory space. The ships perform poorly in ice navigation, station keeping, and maneuvering associated with scientific sampling. The management and maintenance of helicopters are not conducive to their use for scientific purposes and sometimes hinder the science. Ship-to-shore communications are inadequate. Since the mid-1980s, there have been significant changes in USCG ships supporting ocean science. Through decommissioning, the USCG icebreaking fleet has been reduced to the two Polar-class vessels, the Polar Sea and Polar Star. Partly in response to the 1988 NRC report, USCG has made a concerted effort to upgrade the science support provided on the Polar-class vessels. Based on the experience of scientists since 1988, the assessment of USCG icebreaker science support is mixed.* There is evidence of significant improvement in some areas. For example, multidisciplinary science teams of 33 persons were fielded aboard the Polar-class vessels in the Northeast Water Polynya Project (1992 and 1993) and the Arctic Ocean Section (Travis, 1994). New data were obtained in physical, chemical, and biological oceanography. However, in several key areas the USCG icebreaker science support still falls short of that needed to address key questions of arctic marine science. The problems most frequently cited by members of the science parties on recent USCG cruises relate to inexperienced crew, breakdowns and mechanical failures in the ship propulsion systems leading to loss of science time and spatial coverage in the ice, inadequate shipboard laboratory space on the Polar-class vessels, inadequate control of planning and operations as they affect science, and limitations on seasonal and spatial sampling. With reference to seasonal and spatial sampling, many U.S. scientists place a high priority on acquiring new data in the northern Bering Sea, Chukchi Sea, and central Arctic Ocean during winter and spring. Because one or both of the Polar-class vessels operate in the Antarctic at this season, there has been little opportunity for such sampling. (Even if these vessels were available during winter, it is doubtful whether they or any surface ship, except possibly one of * Personal communication to the committee from Arthur Grantz, U.S. Geological Survey, February 22, 1995; Sharon Smith, February 16, 1995, University of Miami; and Walter Tucker, U.S. Army CRREL, February 22, 1995.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS the Russian nuclear-powered icebreakers, could navigate and maneuver effectively in the Chukchi Sea and the central Arctic during the winter-spring season.) Recurring mechanical failures and breakdowns of USCG icebreakers appear to be due to the design of the propulsion system on the Polar-class vessels, together with the difficult ice conditions encountered by vessels in the A5 class. This results in substantial milling of large ice fragments by the controllable-pitch propellers driven by the gas turbines and direct diesel power plants. There is no evidence that these breakdowns will cease in future cruises with the Polar-class vessels. However, according to information provided to the committee by USCG, the Healy will have fixed-pitch propellers and a diesel-electric power plant to attempt to correct the ice-milling problem. USCG representatives informed the committee that the Coast Guard is now conducting a two-year effort to retrofit and upgrade the control and propulsion systems on the Polar-class vessels. Furthermore, it is anticipated that the Healy will operate in less severe ice conditions than those faced by the A5 Polar-class vessels. R/V Alpha Helix—The R/V Alpha Helix is a UNOLS vessel based at the University of Alaska, with modest ice strengthening but no icebreaking capability. Soon to be retired and apparently not to be replaced, the Alpha Helix has performed numerous research cruises, primarily in the North Pacific Ocean, Bering Sea, Chukchi Sea, and Alaskan coastal waters during the past 15 years. Operation of this vessel is restricted primarily to open water, which is a severe limitation during late-summer cruises in the Chukchi Sea. The successful completion of hydrographic sections, biogeochemical stations, and deployment and recovery of moored instrumentation when faced with advancing ice makes operations inefficient and diminishes the scientific return from some cruises. The Alpha Helix does not provide access to the broad shelves of the Bering and Chukchi seas during the winter and the transitional seasons of ice advance and retreat. R/V Nathaniel B. Palmer—Since 1992 the Palmer, operated under contract by Antarctic Support Associates (ASA), has provided research support for the U.S. Antarctic Program. According to the Antarctic Research Vessel Oversight Committee (ARVOC, an ad hoc committee that reports to ASA), there is a high degree of satisfaction in the scientific community that uses the ship. The most significant problems were encountered initially: the technicians aboard ship were inexperienced and incapable of properly maintaining and operating some of the research instrumentation. ARVOC reports that this problem has diminished over the 1992-1995 period, as ASA has improved the staffing of the vessel by employing experienced, technically capable personnel on an ongoing basis. The vessel itself has performed well in maneuverability, icebreaking, and station keeping. Its laboratory space, deck equipment, communications systems, techni-

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS cal support systems, and personnel are all rated highly by participants in research cruises, and demand for the use of the Palmer is guaranteed through 1997.† Submarines in the Arctic U.S. Nuclear Submarines (SSNs) In August-September 1993 the U.S. Navy nuclear submarine Pargo was used for an arctic research program (Langseth et al., 1994). The use of such submarines as arctic research platforms is in its infancy. The Pargo carried a party of five scientists to the central Arctic Ocean, where a 21-day science program was conducted. A second, 43-day science program on the Cavella occurred in March-April 1995 and is the first cruise in a planned five-year scientific program jointly sponsored by the U.S. Navy and several federal agencies, including NSF. The Pargo cruise demonstrated that a small science party could work effectively in an SSN. The vessel obtained hydrographic, ice, chemical, and geophysical data along a 4,900-nautical-mile track. Autonomous data buoys for sampling surface meteorology, sea ice motion, and the temperature-salinity structure of the upper ocean were deployed from the submarine at predetermined locations (Langseth et al., 1994). The technical capability and performance of the U.S. Navy crew were deemed excellent by the scientific party, and an achievement-oriented attitude pervaded the exercise. The platform proved nearly ideal for underway collection of data on gravity, bathymetry, and morphology of the sea ice cover. The cruise also demonstrated that basic physical properties of the upper 1,000 m of the water column, such as temperature and salinity, can be surveyed quickly and efficiently by combining underway deployments of expendable CTD samplers with a set of hydrographic stations where the submarine surfaces through open leads and thin ice. Although the submarine is obviously the best platform for collecting underway profile data on a variety of parameters, such as bathymetry and under-ice morphology, it does have several significant limitations. In their present military configurations, SSNs offer extremely limited space for scientists to live and work, effectively excluding much of the shipboard laboratory work needed for biological and biogeochemical process studies. There is no provision for net tows and trawls that are commonplace in biological studies, and adapting or modifying submarines to accommodate such tows, trawls, and sediment coring † Cornelius Sullivan, NSF Office of Polar Programs, personal communication to the committee, May 2, 1995.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS capabilities would probably be difficult and expensive. For reasons of naval policy, the submarine does not conduct science operations outside a clearly delimited area that encompasses most of the central Arctic Ocean. For reasons of safety, the submarine does not conduct science operations over the ice-covered, shallow (depth less than 100 m) continental shelves or in waters deeper than 800 m. Nuclear-powered vessels also may be legally restricted from operating in certain areas, such as Canadian coastal waters. The presence of a nuclear reactor aboard ship may contaminate samples so they cannot be analyzed for radioactive tracers such as tritium and carbon 14. There may also be problems with international cooperation, because foreign scientists are not allowed to participate in SSN cruises. The issue of access for women scientists to work on submarines would have to be resolved. The deck of the submarine is not designed to facilitate surface deployment of scientific gear, and all such gear must fit through a small hatch. For example, at the Pargo surface stations, profiles of conductivity-temperature-depth (CTD) were limited to depths above 1,000 meters, and bottle samples could not be collected with standard rosettes, because a rosette sampler and full-size CTD winch would not fit through the hatch. Participants in the Pargo cruise were optimistic, however, that these equipment problems could be overcome without major modifications to the submarine itself. They believed that an engineering effort costing many times less than the annual operating costs of a surface ship could make it possible for full-depth CTD and bottle sampling to become a relatively routine component of the submarine scientific cruises. The existing five-year program of one submarine cruise per year (likely to be a different vessel for each cruise) limits the possibility of modifications to support efficient science opportunities. The “White Submarine” concept would overcome these limitations by employing a full-time dedicated submarine, outfitted for science purposes, for a five-to six-year program (Newton and Kauderer, 1994). However, the costs for this program are at present unknown. The Sturgeon class is particularly appropriate for arctic research because it is capable of surfacing through the ice without requiring expensive modifications. Because all the submarines of this class will be retired in five to seven years, the opportunity to acquire one for research purposes will exist only for a limited time. Even if an SSN were to become available for science, its lifetime would be limited, depending on the amount of nuclear fuel remaining (Sturgeon-class submarines cannot be refueled). A scientifically outfitted SSN brings unique capabilities to oceanographic research in the Arctic (Table 8). The principal attribute of an SSN is that its operation is completely independent of surface conditions, whether ice or rough seas; it provides an all-season, all-weather capability for work in the Arctic. The SSN offers a swift, quiet, and stable platform of great endurance that is ideal for underway charting operations. For this purpose SSNs are efficient in terms of data quality, time, and cost. In the Arctic Ocean, SSNs can accom-

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS plish comprehensive geophysical and hydrographic surveying that is usually done from surface ships in open water, and do it far more cost effectively than ice-capable surface ships (see Table 8 and Table 9). The SSN should be viewed as a highly effective, perhaps essential, complement to surface ships and not a replacement. The major impact it would have is to reduce the amount of underway survey work needed from surface ships. TABLE 8 Principal Characteristics of a Demilitarized Sturgeon-class Submarine Equipped for Science Speed Up to 25 knots Depth of operation 0 to 800 meters Practical endurance 90 days Range Unlimited but normal operations restricted to areas with water depths greater than 100 meters Laboratory space About 1,000 square feet Science berths 20 to 25 Operating crew About 70 The SSN could be used effectively in a finite-duration program. During a six-year period a scientifically equipped SSN could contribute significantly to a comprehensive map of a wide range of parameters in the Arctic Ocean: a complete, high-resolution swath map of the arctic basins deeper than 100 m; a complete geophysical map of the arctic basins (magnetic surveys, gravity surveys, high-resolution seismic surveys); a comprehensive map of hydrographic parameters (temperature, oxygen, and salinity) at submerged depths (50 to 240 m) plus closely spaced vertical profiles of the upper 1,000 m using expendable profiling devices. (With existing technology, the submarine systems used to measure temperature, salinity, and water chemistry are less accurate than the systems used aboard surface research vessels, and further development is needed.); synoptic seasonal chart of current directions and speeds in the upper waters of the Arctic Ocean; basinwide synoptic surveys of the chemistry of the upper 200 m of the water column;

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS a five-year inventory of ice volume in the Arctic Ocean, and time-series data on ice deformation and movement as well as ice growth and shrinkage over large areas of the Arctic; and an undersea survey of the extent and duration of ice algae blooms and other information about the distribution of organisms in the Arctic Ocean. TABLE 9 Outfitting a Demilitarized Scientific Submarine Hydrography Recording conductivity, temperature, and depth Up-looking and down-looking acoustic doppler current profiler Enhanced sub-launchable expendable probes for temperature, salinity, oxygen, and current shear profiling Chemical oceanography An uncontaminated seawater sampling system while submerged Capability to sample the shallow water column at discrete depths by means of remotely operated vehicle or autonomous unmanned vehicles Underway ship-mounted chemical sensors Geophysics Swath bathymetry Gravimeter and gravity radiometer Magnetic radiometer High-resolution subseafloor profiler (e.g., parasound or chirp sonar) High-resolution vertical incidence seismic profiling Sea ice studies Up-looking swath mapper of the ice bottom Video imaging of the ice Biological oceanography Submerged sampling capability Midwater acoustic imaging capability Underway ship-mounted color and turbidity sensors General A computer-based integrated data management, quality control, and display system

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS Air-Independent Propulsion Not all of the potential undersea platforms are nuclear powered. Extensive activities (mostly military) focus on developing “air-independent propulsion” (AIP) for conventional, diesel-electric submarines. Sweden has just launched the Gotland, which is powered by sterling cycle engines. Similar naval submarine developments are taking place in Germany, the Netherlands, France, and Italy; however, at present, no U.S. AIP submarines are available. The AIP developmental efforts have resulted in at least four long-duration small submarines for civilian use: the French Saga and three German Seamaid/Seahorse vessels. Military AIP developments will presumably continue to flow into the civil sector to provide long-duration in situ capabilities for marine research, although at high cost. Alternatives to U.S. Ships and Submarines In considering the various scientific requirements and missions for surface research ships, there is also the additional question of whether some or most of these requirements can be met by the use of alternative platforms. It is obvious that alternative platforms may not be entirely satisfactory for some research projects. But the committee's briefing by arctic research scientists also showed that some research projects would not find a dedicated ARV or submarine as useful as other platforms. This section reviews some of the possible alternate platforms. In the context of this section, “platform” means either a fixed or mobile base for support of scientific operations. Because U.S. icebreakers and submarines were discussed earlier, they are not included in this section. However, non-U.S, vessels are discussed briefly. Satellites Earth-orbiting spacecraft, manned or unmanned, provide a powerful and unique tool for large-area sensing and real-time-series measurements. While they are expensive, they can do many tasks that cannot be accomplished by any other means. Satellites can provide a synoptic view of several oceanographic properties. Surface temperature, surface albedo, sea ice extent, and sea ice motion can be measured using satellite remote sensors. Ice thickness can be estimated through the joint use of satellite and ocean observations, and ice topography can be measured by satellite. The National Aeronautics and Space Administration (NASA) plans to launch a Geoscience Laser Altimeter System in 1999 or 2000 that would be useful for such measurements. Earth-orbiting

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS satellites are a mature technology and will be developed and supported through both domestic and international efforts to serve a wide variety of global science, communications, and positioning needs. NASA's Mission to Planet Earth has recognized the importance of Earth-orbiting remote-sensing platforms. Because an orbital path will be over the world ocean from 60-75 percent of the time, ocean research applications could benefit greatly from this NASA initiative. The committee notes, however, that the orbital paths of potentially useful satellites are not now at sufficiently high latitudes to be of much assistance for research projects in the central Arctic. There is a similar problem with the use of communications satellites at high latitudes. This makes communications and data transfer from field sites considerably more difficult than at lower latitudes. This problem should be resolved in the next few years as new communications satellites are put into Earth orbit. For navigation, the U.S.-maintained Global Positioning System (GPS) provides adequate coverage at high latitudes. The comparable Russian GLONOSS positioning system is also available. However, in the Arctic, position locations are good to only 100 m using GPS when selective availability or anti-spoofing features are employed by the satellites. As in the case of the Navy-owned AGORs, it may be possible to equip receivers on research platforms with the keys needed for 10 m accuracy. Aircraft and Remotely Piloted Vehicles General-purpose aircraft in support of arctic field operations have proven their utility. In the United States and Canada, most aircraft support services are operated by private contractors, offering a wide variety of options to put scientific parties on the ice, support them, and retrieve them at the completion of operations. Although these are logistic support operations, many of these aircraft can be configured to conduct aerial survey operations such as photography and remote sensing. These aircraft are funded by the individual scientific programs that require their services. There are also highly specialized, and usually large, aircraft that are specially configured for various types of science support missions. Examples include NASA's ER-2 (U2 variant) aircraft that can undertake long-duration, very high altitude missions, and the Navy's P-3 patrol aircraft specially equipped for surveying geomagnetic and gravity fields. These costly, high-maintenance systems have been supported and operated by the government at little cost to the scientific user. Recently, operators of these large aircraft have been seeking full cost recovery, which puts the operating expenses on a par with those of an icebreaker.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS Military technology has provided the capability to construct and operate small, unmanned aircraft capable of high altitudes and missions that can be several thousand kilometers in duration. These are primarily reconnaissance platforms, equipped with various imaging systems. In the Arctic, remotely piloted vehicles (RPVs) could be operated at long distances from the base station and could provide an alternative to more expensive aircraft. As with helicopters, smaller RPVs can be launched and recovered from ship or ice camp sites. Using remote television links to the base station, RPVs can scout ice conditions in the vicinity of the base, locate animals on the ice, and assist in search-and-rescue operations. The polar research community will benefit from continuing military and intelligence developments in these areas although, at present, the technology transfer process is not well developed. Non-U.S. Vessels Several non-U.S, polar vessels offer advantages (in terms of icebreaking capabilities and endurance) over U.S.-operated vessels. It is difficult to determine from the available list of non-U.S, ice-capable vessels which ones have the necessary space available for scientific research. The best-known non-U.S. vessels are:‡ four Russian nuclear-powered icebreakers, the Arktika, Ymal, Academix Schuleykin, and Professor Multanovsky (Mustafin, 1993); three Russian diesel-powered icebreakers, the Vladimir Kavrayskty, the Otto Schmidt, and the Mikhail Somov (Brigham, 1991); the Akademik Fedorov, a Russian diesel-powered research icebreaker built in Finland (Brigham, 1991); the Australian Aurora Australis (diesel-powered); the German Polarstern (diesel-powered); the Swedish Oden (diesel-powered), accommodates scientific activities in laboratory vans; the Norwegian Polar Duke (diesel-powered), currently chartered by NSF for the Antarctic; and the Canadian Louis St. Laurent (diesel-powered). To obtain specific information about scientific support abilities of the approximately 80 other non-U.S. ships that are ice-capable would require an effort beyond the scope of this report. ‡ Robert Elsner, University of Alaska, personal communication to the committee, May 1995.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS U.S. investigators have used non-U.S, vessels in two modes over the past few decades. In the first mode, exemplified by coordinated experiments such as the Marginal Ice Zone Experiment (MIZEX) and the Coordinated Eastern Arctic Research Experiment (CEAREX), an ice-strengthened non-U.S, vessel was chartered with funds from U.S. agencies, to be used as a research ship in the marginal ice zone or as a research camp moored to the pack ice. Although such charters have provided a wealth of new data and are highly cost effective for programs lacking the funds to support operations and research on the ocean for a large portion of every year, there are significant limitations. The laboratory space aboard such charters is often limited to modifications paid for as part of the charter. Because these spaces may be configured in a one-time, ad hoc modification, safety is a concern. In one experiment, for example, electrical power outlets in such a makeshift laboratory were exposed to leaking seawater. The second mode is for U.S. scientists to participate as investigators on research icebreakers such as Germany's Polarstern, Sweden's Oden, and Russia's Akademik Fedorov. In general, the capabilities and performance of these research icebreakers and their crews have been rated highly by U.S. participants. The primary limitation of this mode of operation is that U.S. investigators must compete for a small and apparently decreasing number of berths available for guests and must adapt their sampling program to the science plan formulated by the primary users of the ship. The limited opportunities for U.S. participation on Polarstern, Oden, and other European vessels may further decrease in the next 5 to 10 years if the “Grand Challenge” program (Johannessen et al., 1994) proposed to the European Union is approved, because this program would make heavy use of the European research icebreaking platforms that now exist. New circumarctic programs may be developed as a result of the International Arctic Science Committee's efforts. These could result in additional needs for U.S. studies as part of an international effort, where the limited availability of research vessels could hamper U.S. ability to respond or participate. In some cases, there is little opportunity for U.S. charter of non-U.S. vessels. Planning by European institutions for the use of these icebreakers generally occurs several years in advance, and excess time and space are often not available. The exception to this generalization may be the Russian icebreakers. It is possible that nuclear or diesel, research or nonresearch Russian icebreakers could be chartered by U.S. agencies to support U.S. arctic science projects, but the situation is far from clear.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS Ice Camps Ice camps are the most basic, simplest, and perhaps lowest cost “platforms” for some applications. In general the locations are stable and they are not space-limited in the area surrounding the site. The camps are usually put onsite, supported, and removed by aircraft or helicopters. There are two types of camps, based on their projected duration. Long-duration camps are those that will be operational for prolonged periods of time and tend to be occupied year-round. Ice islands, such as the former T-3, are examples of this type of camp. Short-term camps are those occupied briefly, usually for a specific purpose or mission. They are highly portable and are usually configured for specific research missions. Often they are satellites of a long-duration camp. When they can be used, ice camps are the platform of choice for many investigators. An ice camp has been used successfully in a number of studies and will be used extensively in the Surface Heat Budget (SHEBA) project planned for spring 1997. Ice camps can provide a long-term station for sampling and an opportunity for coring sediments. They have limitations, however. They do not provide for work in the open ocean or marginal ice zone. They are also unsuitable for horizontal sampling of the water with trawls. Large camps move with the ice and cannot be relocated to specific areas of interest. Small camps cannot support some important science facilities. The cost of ice-camp-based studies can range from $600 to $4,000 per person per day, depending on such factors as the amount of support needed from ships and aircraft for a given experiment.§ Helicopters Small helicopters can be carried aboard research vessels and can be staged from ice camps. Used for both research tasks and logistic support, these vehicles offer a high degree of mobility and operational flexibility. In relation to the machines of just 10 to 15 years ago, modern helicopters are reliable and reasonably easy to maintain in the field. Hovercraft Hovercraft have been used around and over the ice for several years. In theory, they can go anywhere, bearing moderate payloads. Experience with hovercraft has demonstrated several limitations to their use in the arctic § Erick Chiang, Office of Polar Programs, NSF.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS environment. They have a limited range and size and require the support of a base. Large ice ridges may prove impassable, and the vehicle's skirts can be easily damaged by the ice, considerably reducing the hovercraft's efficiency. Buoys, Drifters, and Arrays Many types of data do not require the continuous presence of a human. Fixed buoy systems offer the ability to take long-term measurements and acquire data at sites where the system is not at risk from ice movement. Buoy technology today is sophisticated and can provide the necessary data at a fraction of the cost of manned systems. In open water, data can be transmitted by satellite or by radio to the platforms within range. Oceanographic moorings are anchored to the seafloor under the pack ice, and the shallowest instruments are designed to float 50 to 100 m below the ice. This type of mooring must be deployed and recovered by a surface party, usually aboard a ship, although some moorings have been deployed and recovered through holes drilled in the ice by surface parties transported to the site by aircraft. Arrays tend to be a large assembly of sensors combined to make multiple measurements of a variety of phenomena. Arrays can be moored at mid-water locations or located on the seafloor, depending on the mission requirements. Drifters are buoys that are not constrained by anchors (e.g., Honjo et al., 1995). In general, tracking the trajectory of the drifter buoy provides a means to measure water movements at predetermined depths. Drifters can also have onboard sensors to record basic oceanographic data. In the Arctic Ocean, ice cover provides a uniquely stable platform that can support autonomous instrumentation such as sophisticated electronics packages floating with the sea ice. Such systems can provide extensive time and space coverage of sea ice motions, surface air pressure and other meteorological parameters, ice temperature, ocean currents, and the temperature and salinity of the upper 400 m of the water column. Remotely Operated Vehicles Remotely operated vehicle (ROV) technologies have advanced greatly since their introduction as operational platforms in the early 1970s. Several thousand have been built and put into service worldwide. They have been used successfully under the ice. In fact, NASA operated one under the Ross Ice Shelf in the Antarctic in the early 1990s. This was a telepresence system: the pilot and his control station were several thousand miles away in Sunnyvale, California. ROVs can be deployed from ships, submarines, ice camps, and helicopters.

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ARCTIC OCEAN RESEARCH AND SUPPORTING FACILITIES: NATIONAL NEEDS AND GOALS They come in a variety of sizes ranging from small swimming TV cameras weighing less than 100 pounds to large work vehicles weighing tons. Some may be equipped with fiber optic data links to the base station to permit real-time monitoring of data and to change the mission profiles. The newest developmental direction in ROVs has been in long-penetration/ great-depth missions. A U.S. company is now building a 20-km-penetration ROV that will be used for inspecting water viaducts. By hardening the pressure hull, this could be a 10-km deep-diving vehicle. In late March 1995 the Japanese sent their $60 million Kaiko ROV into the one of the deepest places in the ocean, to a depth of 10,911.4 meters. Operating through holes cut in the ice, a vehicle such as this could make direct visual observations at any point on the seafloor of the Arctic Ocean. Autonomous Unmanned Vehicles The first operational autonomous unmanned vehicle (AUV) was developed by the University of Washington's Applied Physics Laboratory in the 1960s for under-ice work in the Arctic. Range and mission duration were limited, but the system worked well for the time. However, most existing AUVs are experimental, and few operational systems exist. A major limitation is providing sufficient onboard power to support missions that could last weeks instead of days (the present maximum mission duration). When this problem is solved, AUVs can be configured for long-duration missions with transits measured in thousands of kilometers and mission durations measured in weeks. When the power problems are solved, AUVs may replace submarines for many applications. Short-duration AUVs will be the first operational vehicles of this type to be available for arctic research. They can be deployed from ships, submarines, ice camps, and helicopters. Programmed for specific missions, they will be able to make transits of several tens of kilometers at depths down to a few thousand meters.

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