Improved global bathymetry. Final report of SCOR working group 107
(2002). Improved global bathymetry. Final report of SCOR working group 107. Technical Series. Intergovernmental Oceanographic Commission = Série technique, 63. UNESCO: Paris. iv, 108 + annexes pp.
Part of: IOC Technical Series. Intergovernmental Oceanographic Commission = Série technique. UNESCO: Paris. ISSN 0074-1175, more
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| Abstract |
Accurate and detailed knowledge of global bathymetry is a prerequisite for progress in the scientific understanding of the different components of the earth’s global systems, and for intelligent management of global resources. Data on the shape of the seabed are necessary to select sites for communications cables and fisheries, to make inferences about the energy and mineral resource potential of ocean floor structures, to guide computer simulations of the behaviour of the oceans and of climate, and to forecast tsunamis. Improved knowledge of the shape of the seabed is one of the factors required for success of the planetary scale global observing systems (GOOS, the Global Ocean Observing System, and GCOS, the Global Climate Observing System) whose operations will help a larger human population to manage sustainably on an increasingly crowded Earth.SCOR Working Group 107 on Improved Global Bathymetry was charged with: (i) establishing the scientific needs for improved knowledge of ocean depths (i.e., what scientific problems need what measurements?); (ii) specifying the accuracy and resolution requirements needed in different geographical and research areas (e.g. identifying limitations and gaps to be filled); (iii) recommending actions and priorities (such as what parts of the oceans should be tackled first).The group identified a range of topics for which improvements in bathymetry were considered important, and quantified the scientific requirements in terms of horizontal and vertical resolution for a number of them. In the open ocean seawards of the continental shelf and slope there is a progressive increase in the requirement for horizontal (H) and vertical (V) resolutions from 5-10 km (H) and 10-50 m (V) over the open ocean, to 1-5 km (H) and 20 m (V) over open ocean sills, to 250 m (H) and 10 m (V) for abyssal hills, and finally to 100 m (H) and a few metres (V) in rift valleys. On the continental slope there is a requirement for 1 km (H), decreasing to 500 m (H) over canyons and ridges. On the continental shelf this increases further to 100-500 m (H) in water deeper than 10 m, to 50 m (H) in water less than 2.5 m deep.The group identified 6 priority actions for the near future, and made 34 recommendations as to how those priorities could be met and other issues addressed. Several recommendations relate to changes that are required in the policies of national funding agencies so as to facilitate the acquisition of bathymetric data. Bearing in mind the constraints on funding, the working group decided that gathering additional data by ships equipped with swath bathymetry and side-scan sonar systems, though crucially important especially in data gaps, would not be the first priority. Much can be done already by working more effectively and efficiently with what has already been collected, so the initial focus should be on getting more data into the system.We recommend that SCOR arrange the appropriate follow-up action to stimulate implementation. This might require the formation of an appropriate advisory panel, perhaps including some members of SCOR WG 107 for the sake of continuity.Priority 1: Turn equipment on to generate more data (all too often expensive echo-soundingequipment is not turned on, thus wasting the potential to acquire the data – a pennywise/pound foolish approach to scientific management).Priority 2: Digitise the data that are presently available, and send new data automatically and indigital form to data centres.Priority 3: Begin serious investment in data rescue (data archaeology).Priority 4: Encourage cruises to fill the substantial gaps that exist especially in the South Pacific,South Atlantic, Indian, Southern and Arctic Oceans, in the Arabian Sea, in the back-arcbasins between China and Kamchatka, and in places in the North Atlantic and the NorthPacific (e.g. between Hawaii and North America).Priority 5: Use new technology (e.g. drifting floats and autonomous marine vehicles) to gather newdata from large data gaps.Priority 6: Investigate the possibility of acquiring data from commercial ships by voluntary means. |
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