Mapping Bathymetry

Doctoral thesis in Marine Geoscience

Meddelanden från Stockholms universitets institution för geologiska vetenskaper Nº 344

From measurement to applications

Benjamin Hell

2011

Department of Geological Sciences Stockholm University Stockholm Sweden A dissertation for the degree of Doctor of Philosophy in Natural Sciences

Abstract Surface elevation is likely the most fundamental property of our planet. In contrast to land topography, bathymetry, its underwater equivalent, remains uncertain in many parts of the World ocean. Bathymetry is relevant for a wide range of research topics and for a variety of societal needs. Examples, where knowing the exact water depth or the morphology of the seafloor is vital include marine geology, physical oceanography, the propagation of tsunamis and documenting marine habitats. Decisions made at administrative level based on bathymetric data include safety of maritime navigation, spatial planning along the coast, environmental protection and the exploration of the marine resources. This thesis covers different aspects of ocean mapping from the collection of echo sounding data to the application of Digital Bathymetric Models (DBMs) in Quaternary marine geology and physical oceanography. Methods related to DBM compilation are developed, namely a flexible handling and storage solution for heterogeneous sounding data and a method for the interpolation of such data onto a regular lattice. The use of bathymetric data is analyzed in detail for the Baltic Sea. With the wide range of applications found, the needs of the users are varying. However, most applications would benefit from better depth data than what is presently available. Based on glaciogenic landforms found in the Arctic Ocean seafloor morphology, a possible scenario for Quaternary Arctic Ocean glaciation is developed. Our findings suggest large ice shelves around parts of the Arctic Ocean during Marine Isotope Stage 6, 130–200ka. Steered by bathymetry, deep water from the Amerasian Basin of the Arctic Ocean flows over the central Lomonosov Ridge into the Eurasian Basin. This water mass is traced on its continuing way towards Greenland and the Fram Strait. At the Morris Jesup Rise, bathymetry plays an important role in the partial re-circulation of the water into the Amerasian Basin.

Keywords Ocean and coastal mapping · Digital Bathymetric Model · Geogra- phical Information System · Applications of bathymetric data · Baltic Sea · Arctic Ocean · Seafloor morphology · Ocean circulation

Cover: Three-dimensional bathymetric portrayal of parts of the Fram Strait: Molloy Hole (upper left), Molloy Fracture Zone (center to right) and Hoovgaard Ridge (lower left). Fish tessellation derived from M. C. Escher. This thesis consists of a summary chapter and six appended papers, listed here including my contribution to each of them:

Paper 1 B. Hell and M. Jakobsson (2008). A data model and processing environment for ocean-wide bathymetric data compilations. International Hydrographic Review, 9(1): 23–33. Contribution: Developed idea for the presented methods (90%); carried out the technical development (100%); wrote the manuscript (90%, supported by comments from the co-author).

Paper 2 B. Hell and M. Jakobsson (unpublished). Gridding heterogeneous bathymetric data sets with stacked continuous curvature splines in tension. To be submitted for publication in Marine Geophysical Research. Contribution: Developed idea for the presented method (90%); carried out the technical development and programming (100%); tested the method (90%); wrote the manuscript (90%, supported by comments from the co-author).

Paper 3 B. Hell, B. Broman, L. Jakobsson, M. Jakobsson, Å. Magnusson, and P. Wiberg (in review). The use of bathymetric data in society and science: A review from the Baltic Sea. Submitted for publication in AMBIO. Contribution: Developed idea for study together with co-authors (40%); designed the questionnaire (50%); conducted the questionnaire survey and literature review, and analyzed the results (90%); wrote the manuscript (100%, supported by comments from the co-authors).

Paper 4 J. A. Dowdeswell, M. Jakobsson, K. A. Hogan, M. O’Regan, J. Backman, J. Evans, B. Hell, L. Löwemark, C. Marcussen, R. Noormets, C. Ó. Cofaigh, E. Sellén, and M. Sølvsten (2010). High-resolution geophysical observations of the Yermak Plateau and Northern Svalbard margin: Implications for ice-sheet grounding and deep-keeled icebergs. Quarternary Science Reviews, 29: 3518–3531. DOI: 10.1016/j.quascirev.2010.06.002. Contribution: Participated in multibeam and subbottom profiling data collection and processing: Shipboard responsibility for LOMROG 2009 mapping in the for the article relevant areas; collected bathymetric and subbottom profiling data on 2007 and 2009 expeditions; processed bathymetric and subbottom profiling data on both expeditions.

Paper 5 M. Jakobsson, J. Nilsson, M. A. O’Regan, J. Backman, L. Löwemark, J. A. Dowdeswell, L. Mayer, L. Polyak, F. Colleoni, L. Anderson, G. Björk, D. Darby, B. Eriksson, D. Hanslik, B. Hell, C. Marcussen, E. Sellén, and Å. Wallin (2010). An Arctic Ocean ice shelf during MIS 6 constrained by new geophysical and geological data. Quarternary Science Reviews, 29: 3505–3517. DOI: 10.1016/j.quascirev.2010.03.015. Contribution: Participated in multibeam and subbottom profiling data collection and processing: Shipboard responsibility for LOMROG 2009 mapping in the for the article relevant areas; collected bathymetric and subbottom profiling data on 2007 and 2009 expeditions; processed bathymetric and subbottom profiling data on both expeditions. Positioning/navigation in the ice drift for sampling GC10.

Paper 6 G. Björk, L. G. Anderson, M. Jakobsson, D. Antony, B. Eriksson, P. B. Eriksson, B. Hell, S. Hjalmarsson, T. Janzen, S. Jutterström, J. Linders, L. Löwemark, C. Marcussen, K. A. Olsson, B. Rudels, E. Sellén, and M. Sølvsten (2010). Flow of Canadian basin deep water in the Western Eurasian Basin of the Arctic Ocean. Deep-Sea Research I, 57: 577–586. DOI: 10.1016/j.dsr.2010.01.006. Contribution: Participated in bathymetric data collection and processing; commented on the manuscript.

Paper 1 is reprinted with permission by the International Hydrographic Organisation. Paper 4, 5 and 6 are reprinted with permission from Elsevier. Publication status of the papers as of May 3, 2011.

3 Contents

Summary: Mapping bathymetry 0.1 Introduction ...... 7 0.1.1 Measuring bathymetry ...... 7 0.1.2 What bathymetric data are being used for ...... 8 0.2 Aims of this study ...... 9 0.3 Ocean mapping from data collection to the use of DBMs ...... 10 0.3.1 Measuring and mapping bathymetry ...... 10 0.3.2 Hydrographic data processing ...... 14 0.3.3 The compilation of Digital Bathymetric Models ...... 15 0.3.4 The use of bathymetric data ...... 20 0.4 Discussion ...... 27 0.4.1 Tools for DBM compilations ...... 28 0.4.2 Gridding of heterogeneous bathymetric data sets ...... 28 0.4.3 The use of bathymetric data for research and other purposes ...... 30 0.4.4 Quaternary glaciation history of the Arctic Ocean ...... 30 0.4.5 The importance of bathymetry for ocean circulation ...... 32 0.5 Conclusions ...... 32 0.6 Outlook ...... 35 0.7 References ...... 36

Paper 1: Data model and processing environment — Hell and Jakobsson (2008) 1.1 Introduction and background ...... 45 1.2 Errors and uncertainty of bathymetric data ...... 46 1.2.1 Systematic errors ...... 46 1.2.2 Random uncertainty ...... 47 1.3 Metadata: Critical information for error tracking and uncertainty estimation . . . . . 47 1.4 Data storage and analysis capabilities ...... 47 1.4.1 A multi-dimensional data structure ...... 47 1.4.2 Relational database storage ...... 48 1.4.3 Data to be stored ...... 49 1.4.4 Database schema ...... 49 1.5 Database-GIS coupling ...... 51 1.6 Software implementation ...... 51 1.7 Application and outlook: A Digital Bathymetric Model of the North Atlantic . . . . . 51 1.7.1 Tracing DBM problems to their origins ...... 54 1.7.2 The power of an up-to-date sounding database ...... 54 1.8 Conclusions ...... 56 1.9 References ...... 56

Paper 2: Gridding with stacked splines in tension — Hell and Jakobsson (unpublished) 2.1 Introduction ...... 61

4 Contents

2.1.1 Background ...... 62 2.1.2 Variable grid cell sizes ...... 63 2.2 Methods ...... 64 2.2.1 Gridding with stacked continuous curvature splines in tension ...... 64 2.2.2 Study area and bathymetric source data ...... 64 2.3 Results ...... 66 2.4 Discussion ...... 69 2.5 Conclusions ...... 69 2.6 References ...... 70

Paper 3: Use of bathymetric data from the Baltic Sea — Hell et al. (in review) 3.1 Introduction ...... 75 3.1.1 Available bathymetric data for the Baltic Sea ...... 76 3.2 Methods ...... 78 3.2.1 Questionnaire survey ...... 78 3.2.2 Literature analysis ...... 78 3.3 Results ...... 78 3.3.1 Questionnaire survey response ...... 78 3.3.2 Countries performing research involving bathymetric data ...... 79 3.3.3 The present use of depth data ...... 79 3.3.4 Needs regarding bathymetric data ...... 82 3.3.5 The capabilities of high-resolution DBMs ...... 83 3.4 Discussion ...... 84 3.4.1 Possibilities in data collection ...... 86 3.5 Conclusions ...... 86 3.6 References ...... 87

Paper 4: Ice grounding on the Yermak Plateau — Dowdeswell et al. (2010) 4.1 Introduction ...... 93 4.2 Methods ...... 94 4.3 Submarine landforms from swath bathymetry ...... 95 4.3.1 Lineations — streamlined subglacial landforms ...... 95 4.3.2 Large- and small-scale curvilinear features ...... 96 4.3.3 Moat — current overflow channel ...... 97 4.3.4 Largely featureless seafloor — hemipelagic deposits ...... 98 4.3.5 Distribution of landform types ...... 98 4.4 Acoustic stratigraphy of the Yermak Plateau ...... 99 4.4.1 Description ...... 99 4.4.2 Interpretation ...... 100 4.5 Litho/biostratigraphy and age of sediments on the Yermak Plateau ...... 101 4.5.1 ODP cores ...... 101 4.5.2 Short cores ...... 101 4.6 Discussion ...... 103 4.6.1 Evidence for ice-sheet grounding on the Yermak Plateau ...... 103 4.6.2 Sources of deep-keeled icebergs to the Arctic Ocean ...... 104 4.7 Conclusions ...... 105 4.8 References ...... 105

Paper 5: Arctic Ocean ice shelf during MIS 6 — Jakobsson et al. (2010) 5.1 Introduction ...... 109 5.2 Materials and methods ...... 111

5 Contents

5.3 Results ...... 111 5.3.1 Geophysical mapping ...... 111 5.3.2 X-ray identification of ice erosional surfaces ...... 113 5.3.3 Dating of Arctic Ocean glaciogenic bedforms ...... 114 5.3.4 Core-seismic integration on the Yermak Plateau ...... 116 5.4 Discussion ...... 117 5.4.1 An Arctic Ocean Ice Shelf in the Amerasian Basin ...... 117 5.4.2 The role of the Atlantic water influx and the Arctic Ocean cold halocline . 118 5.4.3 An Arctic Ocean ice shelf during MIS 6 versus MIS 2 ...... 118 5.5 Conclusions ...... 119 5.6 References ...... 120

Paper 6: Canadian basin deep water ﬂow in the Western Eurasian Basin — Björk et al. (2010) 6.1 Introduction ...... 125 6.2 Methods ...... 127 6.3 Results ...... 127 6.3.1 Water masses above the deep salinity maximum ...... 128 6.3.2 Water mass structure at section D ...... 129 6.4 Discussion ...... 131 6.5 References ...... 134

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Summary Summary: Mapping bathymetry

Acquisition Processing Data sets Use

Geology Data processing Seaoor morphology Raw data Site survey grids Data cleaning Paleoceanography Sediment dynamics

Oceanography Currents Chart production Historic data Waves and tides Measurement Circulation modeling

DBM compilation Biology Data management Habitat mapping Metadata Regional DBMs Scientiﬁc research Ecosystem monitoring Data analysis Gridding Oﬀshore operations

Archaeology

? Spatial planning Societal needs Clim. change mitigation Wind power Marine resources

Fishery

Nautical charts Seafaring

Paper 1: Hell and Jakobsson (2008) Paper 2: Hell and Jakobsson (unpublished)

Paper 3: Hell et al. (in review) Paper 4: Dowdeswell et al. (2010)

Paper 5: Jakobsson et al. (2010) Paper 6: Björk et al. (2010)

Summary chapter, manuscripts 4–6

Figure 0.1: Aspects of ocean mapping, and how this thesis is related to them tively low spatial resolution and large uncertainties regularly spaced lattice, here referred to as “grid”. under some common geological settings (Sandwell A DBM can be the output of a regionally limited and Smith, 1997). Nevertheless, predicted bathy- site survey, or portray a larger area based on a metry is a major pillar for ocean mapping at large number of heterogeneous source data sets merged regional or global scales (e.g. Amante and Eakins, into one coherent grid. Such compiled DBMs may 2008). portray anything between small regions of a specific sea (e.g. Klenke and Schenke, 2002) to the entire World ocean (e.g. IOC et al., 2003). 0.1.2 What bathymetric data are being used for The amount and heterogeneity of bathymetric Different kinds of bathymetric data sets can be measurements used to compile DBMs and their used to tackle various research questions and soci- heterogeneity pose specific challenges for the com- etal needs. Perhaps the most common use of ba- pilation process and gridding. In order to thor- thymetric data is for production of nautical charts. oughly analyze the data, detailed metadata infor- Maritime navigation, fishery, spatial planning and mation has to be taken into account. Metadata to some extent research activities are carried out should therefore be stored with the data in an with the help of nautical charts or the soundings de- accessible manner. Gridding bathymetric data is picted in the charts. However, many cartographic often challenging because of the enormous differ- and research and other applications profit from ences in data density and quality between different instead using a Digital Bathymetric Model (DBM). regions. Gridding algorithms must be able to sub- “DBM” in the context of this work refers to a com- sample one part of the source data, while inter- pilation of bathymetric measurements, often from polating—or even extrapolating—between other a variety of data sources, and usually provided on a source data points. The goal with such compila-

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Summary Summary: Mapping bathymetry

tributed. 0.3 Ocean mapping from data collection to the use of DBMs Paper 4: “Ice grounding on the Yermak Plateau” 0.3.1 Measuring and mapping bathymetry

12. To relate new geophysical data from Yermak The history of measuring bathymetry with echo Plateau and Northern Svalbard Margin to exist- sounders ing measurements e.g. from the Ocean Drilling The first echo sounder on a research vessel was in- Program (ODP). stalled on the German Meteor in the beginning of 13. To analyze marine glaciogenic landforms ob- the 1920s. The technology in the fields of sonars served in the region, and their implications for and positioning has since evolved tremendously the reconstruction of paleo ice shelves in the (Fig. 0.2). Only single spot measurements could be Arctic. carried out with the first echo sounders. However, 14. To date the glaciogenic landforms and thus the increased efficiency compared to earlier lead the glacial events. line soundings resulted in important findings, such 15. To develop possible scenarios of glacial activ- as the discovery of the Mid Atlantic Ridge dur- ity that can explain the observed marine glacio- ing the Meteor expedition 1925–1927 (e.g. Stocks, genic landforms. 1937). Later single beam echo sounders mapped a con- Paper 5: “Arctic Ocean ice shelf during MIS 6” tinuous profile underneath the ship track. This added a wealth of knowledge about previously 16. To investigate the hypothesis of Quaternary unexplored parts of the World ocean, especially Arctic Ocean ice shelves using newly acquired during the 1960s and 1970s, when many mer- geophysical data from the Arctic Ocean north chant ships were equipped with echo sounders of Greenland and Svalbard. under their ordinary voyages. The single beam 17. To confirm or constrain Quaternary circum ocean mapping activity peaked in 1972 (Smith, or pan Arctic ice shelves with new bathymetric 1993)—more than a decade before satellite navi- measurements in the Arctic Ocean. gation became available. 18. To analyze the spatial distribution and water Nowadays, mapping bathymetry is carried out depths of seafloor morphological evidence of ice with multibeam echo sounders fully covering a shelves or large icebergs in order to reconstruct strip of the seafloor underneath the ship track of past maximum marine glacial extension in the about three to eight times the water depth in width, Arctic Ocean. by aiming a fan of focused beams towards the sea 19. To constrain the time interval of the maximum floor perpendicular to the ship track and measur- marine glacial extension in the Arctic Ocean. ing the time delay and direction of each beam. With several parallel courses entire regions can be mapped with complete two-dimensional coverage, Paper 6: “Canadian basin deep water ﬂow in the “ensonification”, of the seafloor at high spatial Western Eurasian Basin” resolution and accuracy.

With this full coverage has come an unprece- 20. To investigate how important details in the dented new perspective of seafloor morphol- bathymetry steer the exchange of deep-water ogy and seafloor processes that has been as between and into the different Arctic Ocean revolutionary to those studying the seafloor basins. as the first aerial photographs and satellite 21. To map deep water from the Canadian Basin images must have been to those studying ter- of the Arctic Ocean circulating in the Amundsen restrial earth processes. (Mayer, 2006) Basin. 22. To assess the reliability of existing bathyme- The first multibeam echo sounder on a research tric maps of the Arctic Ocean in the area of vessel was installed on the French Jean Charcot in the Lomonosov Ridge north of Greenland for 1977, but multibeam echo sounders only became oceanographic studies. widespread in civilian use since the 1990s. The

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Summary Summary: Mapping bathymetry

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(xS , yS ,zS ) f o o t p r i n t

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Figure 0.2: Multibeam echo sounder principle: The signal sent out from the along keel transmit transducer array (red) ensonifies a narrow strip on the seafloor perpendicular to the ship’s keel. By applying phase shifts to the return signal at the across keel receive transducer array, an along keel strip on the seafloor is listened at (blue). The intersection of transmit and receive footprint constitutes the area ensonified by one “beam”. Different phase shifts at the receiver result in a different “beam” of the swath. As the ship moves along, a wide strip of seafloor is mapped, with swath angles β typically around 65°. Because sound speed c(z) is not constant, refraction causes the “beam” to be crooked. The conversion of beam angle α and measured time delay ∆t into a sounding (xS, yS,zS) is therefore done by ray- tracing from the transducers (xT , yT ,zT ) under consideration of the sound speed profile through the water column c(z) and the transducer orientation (φT ,θT ,ψT ). always includes a highly accurate inertial motion water column this is done by ray tracing before the sensor and a positioning system to keep track of beams are processed from the received signal. The the vessel’s orientation and position in space. For evolution of sonar techonology is rapid. Poten- each detection α and ∆t, position (xT , yT ,zT ) as tial developments in the future include synthetic well as roll, pitch and yaw angles (φT ,θT ,ψT ) are aperture techniques and high bandwidth frequency recorded, too. modulated signals (Mayer, 2006). Sonar technology is still evolving, and new developments, particularly in signal processing, keep Acquiring multibeam data in sea ice covered areas increasing spatial resolution and accuracy of the measurements. For each ping, modern multibeam Large parts of the bathymetric data from the Arc- sonars measure several hundred beams, or with the tic Ocean used in papers 4–6 were measured under most recent technology rather seafloor detections. a perennial sea ice cover with the multibeam echo The latest generation of multibeam echo sounders sounder installed on I/B Oden. In sea ice and from is capable of delivering a spatial resolution of up an icebreaker, the acquisition of multibeam echo to 10m at 1000m water depth, scaling approxi- sounding data poses specific challenges, which de- mately linearly with water depth. Such systems teriorate data quality in comparison to the circum- are fully compensated for vessel motion, includ- stances on a regular survey vessel. (1) The noise ing yaw and heading. The beam angles at the level of an icebreaker is generally high compared transducer may be optimized to yield equidistant to survey vessels specifically designed for low ship spacing of the soundings on the seafloor. Under noise, making the detection of the faint sonar sig- full consideration of the sound speed profile in the nals more difficult. (2) During ice breaking, the

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( ship zones crooked ice in open resulting steered or often weak is preferable Navigation by (5) system. the acous- the of the shield tics to deteriorates needed also protection transducers ice delicate The transduc- (4) the of ers. vicinity the the alter in bubbles properties air acoustic and the slush even Ice ice (3) sometimes to transducers. and due propellers further, hull, even hitting increased is level noise e c odtos eeaqie na on acquired were heav- conditions, slightly in ice 112), ier page Lomo- on southern 2b the (Fig. from Ridge nosov data The 112). page on the with mapped technique were Rise Jesup ris chirp on details pro for sonar 4 paper (see heading and uneven speed the from data suffers sonar simultaneously chirp acquired Subbottom (2) towards beams. swaths outer the the between distances creasing possible. time ship least This way. under lity the be can breaking fi ice location, next the to of transit order the on typically mapping complete, to mapped overlap. the to for circles enough short distances at neuvers possible usually is it to width, swath thus and swath depth possible greater much and a quality for allows data This higher power. full at breaking ice creates ice, ship, weaker of the signi zone Spinning small a side. in preferably port the towards once soni s roiywtothvn ocnie aaqua- data consider to having without priority rst h ehdhstomjrdisadvantages. major two has method The I/B takes turn full One greater depths water at mapping deep-water For fi fi dsial oain o uhsinn ma- spinning such for locations suitable nd fi dtie newt h tror em and beams starboard the with once twice, ed rudtehaigai,acrl fsea of circle a axis, heading the around atyls os,iesuhadbblsthan bubbles and slush ice noise, less cantly 2 fi sea in o civn ml oeaei the in coverage ample achieving for cient 500m ” fi fl ig.I ae ,teaeso h Mor- the on areas the 5, paper In ling). n> in o at oor taeywsdvlpd which developed, was strategy a , 2m 1000m hc ut-ersaie(i.2a (Fig. ice sea multi-year thick “ ioet technique pirouette fi inl aevrbe(Ja- maneuverable ciently ae et.Udrthe Under depth. water Oden e minutes few a fi in water cient “ “ pirouette straight “ ” leads proved fi fl cult oor ” ” ), . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 OE/oedn(ue l,19)a ela Jason- as well as 1994) al., et (Fu TOPEX/Poseidon n ao-,telte en h ltomfor platform the being latter the Jason-2, and 1 nteogigTnE- rjc Kigre al., et (Krieger 2007). project TanDEM-X ongoing and the 2007) in al., Shuttle et the (Farr on Mission Topography topography Radar land map e.g. to have used instruments been Microwave (Drinkwa- 2007). geoid al., the et of ter shape the gravity survey GOCE to the meter surface, Earth monitor the to on 2006) processes al., et (Williams program LAND- SAT the as such al., platforms et multi-spectral 2005), (Schutz cryosphere the exploring mission Sat LiDAR include Examples ties. very be to proven have ef and globe can entire sensors the map various Remote carrying spacecraft intriguing. sensing are heights orbital from satellite depth water sensing 2006), remotely Hall, for 2000; possibilities al., et (Vogt sound- measurements echo ing with com- ocean World of the covering problem pletely fundamental the Considering bathymetry for mapping altimetry satellite of weaknesses and strengths The icebreaker. leading a behind course bu nnw sub-sea unknown about assumptions dis- effects, be bathymetry cannot from height tinguished surface sea sub-sea the of Smith on effect structures 1994; the As Sandwell, 1997). and Sandwell, and Smith 1983; (Dixon derived al., be et may bathymetry the of mation kilometers. of hundreds or tens of decimeters distances of over order the on are result- bathymetry undulations from ing height water surface sea by The determined depth. gravity largely marine is the which into anomaly, inverted be undu- may height surface lations sea of Thus, surface gravity. equipotential constant an be the would factors, surface dynamic sea latter, the for pres- Corrected atmospheric sure. and stress wind tides, currents, sub-sea sea and includes sea topography This small to anomalies. lead height surface factors of number a However, 2010). al., (Lambin et Mission Topography Surface Ocean the include undu- missions recent height al., more surface Important et sea lations. 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Summary Summary: Mapping bathymetry be made and the derived bathymetry should be smaller gaps between echo sounding data may be a calibrated with ship soundings. smaller disadvantage than often assumed. Jakobs- Deriving bathymetry from satellite altimetry son et al. (2000) showed that even in an ocean as measurements has one big advantage over ship- remote as the Arctic sufficient data for compiling a board echo sounding, namely achieving almost DBM may be obtained. In comparison to the Arc- complete coverage of the World ocean very effi- tic Ocean, for example the North Atlantic Ocean ciently. With the majority of the ocean unmapped appears very well mapped. with echo sounding data, this advantage cannot be stressed enough. 0.3.2 Hydrographic data processing On the other side, satellite altimetry data has significant problems for the derivation of bathyme- The raw multibeam data consists of beam angles α try. (1) The spatial resolution of altimetry-derived and corresponding two-way travel times ∆t of the bathymetry is limited by the smoothing taking detections from each ping, as well as additional place when observing bathymetry through its ef- information needed to convert angles and ranges fect on the sea surface several kilometers away into the (xS, yS,zS) sounding triplets. This includes (Sandwell and Smith, 1997; Smith and Sandwell, a sound speed profile c(z) through the water col- 1997). Typically, a resolution of 10km to 15km umn as well as position (xT , yT ,zT ) and orientation may be achieved, though this figure might change (φT ,θT ,ψT ) of the transducers at the time of each with the data of the most recent missions. (2) Ar- ping. The conversion of beam angles and ranges eas with complex and thick sediment layers un- into soundings is carried out using ray tracing, ei- der the seafloor impose problems in the inversion ther directly in the echo sounder computer or as process, as assumptions about the density distribu- the first step of post processing. tion underneath the seafloor must be made. The In the next processing step, the soundings are effect of inhomogeneous density cannot fully be corrected for the height of the tide at the time of distinguished from bathymetric effects. Altimetry- the measurement, usually by subtracting a locally derived bathymetry is particularly problematic on or regionally valid tide model. In the open ocean continental shelves. (3) Noise in the altimeter data tide amplitudes are most often negligible in com- shows up as a typical “orange peel” fabric, es- parison to the water depths and no tide correction pecially in the bathymetry of flat areas, such as is applied. abyssal plains (Goff et al., 2004; Marks et al., Flagging spurious soundings and obvious out- 2010). (4) Perennially sea ice covered areas such liers in the data is the most time consuming part as the Arctic Ocean impose additional limitations of the processing workflow. If flawed data is not for satellite altimetry (Laxon and McAdoo, 1994). removed, spikes and other artifacts deteriorate (5) The inclined orbits of the satellites commonly the final bathymetric surface. On the other side, used for altimetry-derived bathymetry do not cover special care has to be taken to not remove real fea- all oceans at high latitudes. tures of significance. Examples include the mast of DBMs based on a combination of satellite altime- a wreck when working towards a nautical chart, try and echo sounding data (Smith and Sandwell, or pockmarks on the seafloor that are interesting 1997; U. S. Department of Commerce et al., 2006; for geological applications. Three-dimensional Amante and Eakins, 2008; GEBCO, 2008; Becker visualization and data cleaning techniques aided et al., 2009) offer a coherent and realistic portrayal by statistics, such as the “Combined Uncertainty of the seafloor morphology at global or ocean-wide and Bathymetry Estimator” (CUBE) algorithm, are scales, especially in areas largely devoid of ship- relatively new developments in this field (Mayer, board measurements, such as the Southern Ocean. 2006). Here, purely sounding based DBMs, such as the The CUBE algorithm (Calder and Mayer, 2003) General Bathymetric Chart of the Ocean (GEBCO) assigns 3D uncertainty estimates to each sounding, centennial atlas (IOC et al., 2003) feature a lot based on a comprehensive error model for the echo less detail. However, in some oceans the sound- sounder used. A grid of regularly spaced nodes is ing database may allow for DBMs not having to projected onto the survey area, and each sounding rely upon altimetry measurements. In comparison is assigned to its closest node. Based on error prop- to the resolution power of satellite altimetry on agation, the depth information in each sounding is the order of 10km, interpolation over many of the projected onto the grid node, where the projections

14 ihasge netit ons information bounds, uncertainty assigned with h olwt hsatcei odvlpadtest and develop to is article this with goal The Hl n aoso,2008) Jakobsson, and (Hell hr onig rdphcnor a egener- be may ated. contours depth or soundings chart the is processing. data pack- bathymetric software for major ages all in implemented is CUBE are parameters bene statistical additional of an grids of form the Bi-products in use. widespread into enormously came CUBE increased since has ef work the cleaning user, data the by of touched be to soundings have most never As circumstances. suitable given most the the under be to which appears deciding hypothesis of depth form the in required is processor occur. may for value possibilities depth additional the cell, grid are the measurements in erroneous present If node. value grid depth the likely at one Together for overlap. account cell soundings grid the the in soundings all of bu h aasuc,mauigadpositioning and measuring source, data the about complete only is sounding A the process. for compilation information valuable carry metadata ple, set data global the ca. for SRTM30_PLUS. of used number records higher million even 300 an reports (2009) al. data source signi multibeam af- points, sub-sampled data having million ter seven than less grid- from was example, ded for IBCAO, millions samples; of depth hundreds of or tens incorporate DBMs the study case a tested. In are sets. methods data source the quanti to signed be can how measures (2) and uncertainty soundings, million of of hundreds order or the tens on amounts data ef enormous to the handle how DBM (1) concerning proposed: are questions compilations key two So- for compilations. lutions DBM for needed as their metadata, with together of data analysis sounding and heterogeneous retrieval storage, the for methods handling and storage metadata and data Bathymetric 0.3.3 pr rmtepsto n et fec sam- each of depth and position the from Apart regional of compilation the for sets data Typical work this In data the from interaction case, latter this in Only fi fi aty(aoso ta. 08) ekret Becker 2008a). al., et (Jakobsson cantly Models Bathymetric Digital of compilation The a aapout rmwihmpsheets, map which from product, data nal fl w h rdgnrtdb CUBE by generated grid the ow, fi ftemto.Nowadays, method. the of t fi dadas- and ed fi fi ciently ciency . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 ol ca elmpe.Hwvr oto the of most However, mapped. well ocean World GnrlBtyercCato h cas 2011) Oceans, the of Chart Bathymetric (General with solution integrated an article, this In (GIS). Systems Information Geographical and (RDBMS) iulzto n nlsscpblte faGSal- GIS a of capabilities analysis and visualization h oplto faDMwt mrvdaccuracy improved with DBM a of compilation for sounding the surveys, up-to-date multibeam which recent an presented, including of database, is potential study the case shows A 2006). al., Commerce et of Department S. (U. ETOPO2v2 and GEBCO namely in DBMs, global included used yet commonly not the discussion) (see time article the at this were of region this from data bathymetric GIS. a and RDBMS spatial a on is based capabilities presented, analysis data and management data systems management database relational spatial removed. be should sources reliable less or lower quality from dense data and other quality exam- measurements, high multibeam For with covered areas metadata. in ple and properties regards with spatial analyzed to be pro- should compilation data DBM these the cess, In preparation. involved its steps in processing the and used equipment epriindee ute ystoring by further may even metadata partitioned The be sounding. every with not and positioning SIT fi with ca. navigation, typically satellite car- TRANSIT been using have out may ried survey beam single For a avoided. example, be generally should records data dant accessible. easily more im- records of metadata copies portant stores but CSDGM, the here implements presented solution database The formation. de Both a 1998). FGDC, (CSDGM, Metadata Geospatial Digital for and Standard Content 2003) FGDC 211, the (ISO/TC 19115 ISO/FDIS data: geoscienti for Two exist standards metadata assigned. accepted uncertainties equip- realistic sounding with and ment positioning as Of well plat- as measurement form defects. origin, are data compiled interest underlying a particular possible in problems to of DBM tracing easy for low powerful the data, the with included is metadata com- handling data for georeferenced Tools plex GIS: and database Relational resolution. spatial and in osoetemtdt information metadata the store to cient fl h ot tatci oprdt h eto the of rest the to compared is Atlantic North The include challenges these tackling for Tools hnsoigifraini aaaeredun- database a in information storing When xbe etdte tutr o eaaain- metadata for structure tree nested exible, 500m ” nefrti atclrsurvey, particular this for once oiinn cuay ti suf- is It accuracy. positioning facmrhniestof set comprehensive a If “ accuracy “ TRAN- fi ne fi 15 c

Summary Summary: Mapping bathymetry

500m” only once in a table containing nothing but views”. This strategy was implemented in our so- positioning systems related metadata. In this way, lution. all data records may be partitioned into the various tables of the database schema. The entity our data- Assigning uncertainty margins to bathymetric data base solution is centered around is surveys or pro- The uncertainty of a compiled DBM is dependant cessed data sets, i.e. sets of soundings, which share on the source data uncertainty and the uncertainty common metadata. The different metadata can propagation through the gridding process. then be perceived as additional dimensions to the Smith (1993) demonstrated that significant sys- data in a multi dimensional cube. From a RDBMS tematic errors can be expected in a few percent of point of view, such a data structure corresponds all archived single beam bathymetric data. These to a star-shaped database schema (Kimball and errors come from a number of sources, such as Ross, 2002), with a central fact table of surveys erroneous assumptions about units during travel surrounded by dimension tables, containing meta- time to depth conversions or flawed paper readings data such as positioning systems, sounding equip- from instruments. If not detected and corrected, ments or data sources. These star schemata allow such errors can in extreme cases bias entire DBM for efficient retrieval of data based on metadata, regions (Jakobsson et al., 2008a). In combination e.g. queries such as “display all surveys from the with correct data these errors usually manifest in 1980s with GPS positioning”. The actual sound- artifacts along the respective track line, which may ing data in the implemented schema are principally lead to premature interpretations of seafloor mor- treated as a data dimension as well and also stored phology (Wheeler and Phillips, 2009). When try- in a dimension table. This allows for queries such ing to find systematic errors, e.g. using cross track as the retrieval of all surveys containing soundings differences (Wessel, 1989), metadata is valuable in a specific region. Furthermore, the actual sound- information. For instance, errors due to measur- ings are not needed for many analyses, where e.g. ing sound speed in fathoms per second are unlikely the overall extent of a survey is sufficient. when the data are obtained from a non-American Our solution includes a complex database source. schema and the use of pre-defined queries (views) In contrast to modern multibeam surveys follow- for accessing the underlying database tables with ing established quality standards (IHO, 2008), the a GIS. This structure is universally adequate for uncertainty of historic single beam data is often all kinds of sounding data, be it spot soundings not specified. In such cases, uncertainty margins (points), single beam tracks, digitized depth con- can be based on metadata information, assigning tours from charts (both lines) or gridded multi- typical uncertainties for the positioning and sound- beam surveys (polygons). However, because of ing equipment used. This approach was chosen the large amount of samples in high-resolution by (Jakobsson et al., 2002). If applicable, more multibeam grids, such data usually needs to be sub- sophisticated error models could be applied (Hare sampled to a data density appropriate for DBM et al., 1995; Marks and Smith, 2009). How the compilation prior to the database storage. The uncertainty propagation through the DBM com- data retrieval in a spatial RDBMS through SQL pilation process can be handled depends largely queries allows for flexible and powerful analysis on the gridding method used. However, Monte and processing capabilities. Carlo simulation, as described by Jakobsson et al. Common GIS software is not capable of directly (2002), is a method that can be universally applied accessing a complex database schema with mul- if the computational costs permit. tiple related tables, but needs the data be stored in single, two-dimensional tables. SQL queries Testing the database and GIS approach We tested the always return the results in form of a single data capabilities of the proposed database and GIS in table. Therefore, by using pre-defined SQL queries, an area of the North Atlantic Ocean off the U.S. “views”, simple interfaces for GIS software can be east coast, where very heterogeneous data sets are defined in the database. The drawback of views available within a confined area. Without prior is the computational costs of executing the under- cleaning, the source data was compiled into two lying query every time the view is accessed. To DBMs based on only single beam measurements overcome this problem, some RDBMS are capa- and a combination of single beam and multibeam ble of caching views in the form of “materialized data. By visualizing source data and compiled

16 hc a enwdsra sg nteoenmap- ocean the in usage widespread seen has which aueslnsi eso SihadWse,1990), Wessel, and (Smith tension in splines vature ore noachrn omtsilrqie lot a requires still format coherent a various into from sources data Loading metadata. data related sounding and analyze and ef visualize, an manage, be to to proved database relational a sea the in enormously. details increases small portrayal of level the sam- and multibeam ples, of amount sheer are the tracks by beam suppressed single between due mismatch artifacts slight gridding to up, show single DBM purely based the beam in a apparent in not to Features lead DBM. can data multibeam high-resolution compilation. the from discarded or corrected ate—, and marked datasets be Such could then errors. the were assessing records when metadata helpful the often the and in data, observed source be could above mentioned errors data easily could source DBM to the related in be artifacts GIS, the in DBM rithm. re another and splines tension curvature in continuous to superior yields results method an gridding In our published. example, been application has it since community ping cur- continuous upon builds in method The splines tension. curvature continuous stacked sented, topographic or bathymetric measurements. of used gridding commonly are the them for of number small problems, a of and kinds different for exist methods ding as known pattern is regular nodes grid a of into property a of measurements spaced irregularly sub-sampling and interpolating reg- or on lattices, available spaced be ularly to property the other require the hand, on applications, Many as transects. such or locations, point spaced irregularly at or sampled measured in- commonly are geosciences, bathymetry, the cluding in relevant properties Many review) in al., et (Hell Models Bathymetric Digital of compilation the for data bathymetric Gridding laborious. and necessary are many decisions metadata, informed consistent and complete the of reach goal To comprehensiveness. and for- quality to mat, regard with tremendously varies metadata dif is which work, of nti ril,anvlgidn ehdi pre- is method gridding novel a article, this In and GIS a with compilation DBM Approaching improvements, potential the show also tests Our fi utt uoae Especially automate. to cult “ “ fl fi gridding grids w.Alo h typical the of All aws. e piebsdalgo- spline-based ned ” h rcs of process The . ” aiu grid- Various . — fappropri- if fi in way cient fl oor . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 arne ytesuc aatesle.T gain To themselves. data source the by warranted with ( iulypesn n emnl oeetgisare grids coherent seemingly and pleasing visually values onswt iiie oa qae uvtr of curvature squared data total source minimized of with set points a im- connect splines an Bicubic (Briggs, 1974). is interpolation splines (1990) bicubic Wessel of and provement Smith by gorithm poorly in surfaces regions. unrealistic constrained or lines source track along data artifacts e.g. without results gridded coherently delivering of capable Only are algorithms areas. few constrained poorly in even preferred, map-making, for Especially with areas data. in source constrained sparse poorly only many cells leaving grid sets, data source high-resolution of of resolution the the gridding, when possible as details may lines beam be single between re- distance un-surveyed the largely gions other, In less. at or points distance data with covered often multibeam are sonars modern with tremen- surveyed varies Areas compilations dously. DBM for used data n eslitoue parameter a introduced Smith Wessel surface, and interpolated the over control more not are which grid, the in features spurious surrounding as pear arti of Such values points. the ex- data off such source far data, lie source may the trema the of on values Depending and spacing points. data source between the and space, 3D the in points through passes it to Physi- analog is splines. this bicubic cally natural are equation this equation differential the to leads through surface a curvature of minimizing that showed (1974) Briggs i.e. surface, fitted the f x i i h otnoscraueslnsi eso al- tension in splines curvature continuous The source the of density the before, mentioned As nbcbcslns xrm a xs anywhere exist may extrema splines, bicubic In a ergre stewihsnee tthe at needed weights the as regarded be may , 100km y fi i a rdi fe hsni codnet that to accordance in chosen often is grid nal f ) i ( ofr hsshape. this form to x uhta h ouinapproaches solution the that such , y ∇ ) rmr.T rsrea aysmall many as preserve To more. or 2 approaching ( ∇ A Ï 2 z ) ( = ∇ 2 N i X N z = fl ) 1 oredt points data source 2 xn ea lt othat so plate metal a exing f d i δ x ( ( d x x y i fi − , → y a xrm a ap- may extrema cal x i ) i min h ouinof solution The . , y − y T i I ) nBriggs in ( x i , 100m z y (0.1) i i , for z 17 i ) ’

Summary Summary: Mapping bathymetry equation (0.1), representing internal tension: gridded at high resolution and vice versa. With stacked continuous splines in tension it is possible N 2 2 2 X to choose the highest grid resolution according to (1 TI ) ( z) TI z fi δ(x xi , y yi ) − ∇ ∇ − ∇ = i 1 − − the highest-resolution source data and still grid = (0.2) sparsely constrained areas at a more appropriate, lower resolution. The method is implemented us- Increasing internal tension relaxes the minimizing ing software from the open source Generic Map- of the curvature and concentrates curvature at the ping Tools (GMT, Wessel and Smith, 1998), which source data points. With T 0 equation (0.2) re- I = was adopted to include the masking and stacking duces to Briggs’ original equation (0.1), whereas functionality. the other extreme T 1 is physically analog to I = We tested our method with a heterogeneous infinite tension, without any local minima and sounding data set from the Arctic Ocean and maxima possible except at the source data points. compared it to conventional continuous curvature Smith and Wessel (1990) developed an efficient splines in tension as well as the remove-restore finite difference algorithm to solve equation (0.2) method (Forsberg and Tscherning, 1981; Forsberg, the modified equation with a number of bound- 1993; Torge, 2001, 281ff.). Remove-restore as im- ary conditions. Continuous curvature splines in plemented by Becker et al. (2009) also incorporates tension are probably the interpolation algorithm spline interpolation and aims at preserving little most commonly used for DBM compilations. small details from high resolution source data. Several problems remain with continuous curva- The source data for our tests comprises one half ture splines in tension. (1) As the processes shap- million data points, with multibeam grids of differ- ing the earth’s surface arguably do not minimize ent resolutions covering two thirds of the area and curvature, the method usually results in surfaces single beam data the rest. The densest source data that are unnaturally smooth. (2) Areas with poor has a resolution of 100m, and the largest gaps in data control in the form of sparse measurements the data set are on the order of 50km2. on straight lines (e.g. single beam echo sounding With the stacked splines and remove-restore tracks) are prone to artifacts along the grid lines, methods, grids at a resolution of 500m were especially at relatively high grid resolutions. (3) As prepared. Probably even higher grid resolutions a consequence, the grid resolution has to be cho- would have been possible and beneficial for the sen balancing the highest possible level of details densely source data covered areas; however, such against gridding artifacts in poorly constrained re- high resolutions are not common for deep sea map- gions. Therefore in areas with high-resolution data ping purposes. With splines in tension, a grid re- often details are lost, adding to the first mentioned solution of 1km could be achieved, as higher reso- problem. (4) Without knowing the locations of lutions led to inferior results because of gridding the source data, it is not possible for the end users artifacts. of the gridded data to distinguish whether smooth A comparison of the grids shows that our im- areas with only little detail in the morphology are proved method gives the best results in terms of a naturally smooth or only due to a lack of measure- balance between resolving small details on the one ments. hand and suppressing different types of gridding The method presented here improves upon all artifacts on the other hand (Fig. 0.3). It yields the four of these issues. The idea is to grid the source highest level of small details of all three methods data at different resolutions using splines in ten- as well as an overall visually pleasing and coherent sion and remove the parts of each grid that are surface. As an extra benefit, a grid with the val- not sufficiently constrained by source data. Then ues of the highest possible grid resolution for each the grids are stacked onto each other with higher place can be produced. This may be interpreted as resolution grid cells overruling lower resolutions the factor by which the DBM may be sub-sampled ones where possible. In a final and optional step, at a given place without losing information. For the stacked grid nodes can be taken as input for the end users of the DBM this can be valuable another interpolation onto a grid with constant information about the local data quality. resolution. Apart from the improvement of gridding meth- The result is a grid with properties reflecting ods, the aims of this study included the question the source data: Areas with dense source data are how to determine grid resolution. Our solution for

18 in(ide n pie ntninbsdrmv-etr bto) iwn ieto otws,vria exaggera- vertical northwest, direction Viewing (bottom). 6×. remove-restore tion based tension in splines and (middle) sion 0.3: Figure oprsno tce otnoscraueslnsi eso tp,cniuu uvtr pie nten- in splines curvature continuous (top), tension in splines curvature continuous stacked of Comparison . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 tce splines Stacked pie ntension in Splines Remove-restore 19

Summary Summary: Mapping bathymetry this problem is steered by the source data rather Results and discussion The study reveals a broad than e.g. seafloor morphology. Stacked splines in variety of applications for bathymetric data. In the tension is carried out at varying resolution, in each questionnaire answers, three fields are dominant, place adjusted to the density of the source data. namely spatial planning (water resources, fishery, energy, exploration and environmental protection), different numerical modeling applications (circu- 0.3.4 The use of bathymetric data: Case studies lation, transport mechanisms and habitats) and from shallow water areas and the deep research related uses (ecology, climate change, ar- ocean chaeology, geomorphology). The most common The use of shallow water bathymetric data in research disciplines from the scientific literature are physi- and for societal needs (Hell et al., in review) cal oceanography (circulation, climate, waves and tides), marine geology (sedimentation, seafloor dy- Introduction and methods For data providers, the namics, paleotopography) and, less commonly, bi- question what purposes bathymetric data are being ology/ecology (processes and habitat mapping). used for, what problems end users or bathymetric The IOWTOPO DBMs and depths from nauti- data are confronted with and what specific needs cal charts are by far the most commonly used data. they have, are important in order to maximize the IOWTOPO is more common in the research com- usability of their data sets. This article shades a munity whereas the authorities, where the focus light on such questions, in a case study for the often lies closer to the coast, use chart depths more Baltic Sea. The study focuses on research uses and frequently. In a number of occasions, data was applications for societal needs in the public sector, specially produced for a project, as the available mostly at state authorities, based on a question- data sets were not appropriate. In almost all ques- naire survey and a review of the scientific literature. tionnaire answers, deficiencies of the data sets used This study is less relevant with regard to industrial are pointed out. Three quarters of the users, espe- and business applications of bathymetric data. We cially those concerned with shallow water work, also show the potential of releasing bathymetric express that the level of detail or the spatial reso- data collected primarily for safety of navigation, lution of the data is not sufficient. Almost half of i.e. the source data for the production of nautical the users criticize a general lack of measurements, charts, to satisfy the needs of the research commu- and about one quarter complain about difficulties nity and the public. due to the fact that detailed bathymetric data are A number of other bathymetric data sets ex- confidential information in Sweden. ist for the Baltic Sea area, each of them with its Because research is usually not published on own advantages and drawbacks and none ideally the basis of insufficient data, only few indications suited for a wide range of applications. Presently, about similar problems can be found in the litera- no up-to-date, regularly maintained and quality ture. A recurring example is IOWTOPO being re- controlled DBM is available for the Baltic Sea. The sampled to a higher grid resolution for some stud- most important DBM, and the one most used, is ies. In several studies the geographical area of in- IOWTOPO (Seifert et al., 2001), in the form of terest is influenced by the extent of the IOWTOPO two grids covering the entire Baltic Sea at ca. 2km DBMs rather than subdivisions of seas or marine grid node spacing and the southern Baltic and Belts regimes. at ca. 1km. The needs expressed in the questionnaire an- For this study, 32 Swedish users of Baltic Sea swers suggest that an optimal data basis covering bathymetry data were sent a questionnaire with most applications would be a DBM with a resolu- detailed questions about their applications and tion on the order of 5m to 25m; the closer to the needs. The questionnaire was answered by 21 re- coast the higher the required resolution. Such a cipients, with response rate being high from state DBM should cover particularly coastal areas shal- authorities, lower for the research community and lower than ca. 40m, and integrate seamlessly with zero when it comes to non-governmental organi- a Digital Terrain Model portraying coastal land el- zations. To gain deeper insight into research re- evations. The interest in shallow areas close to the lated needs, the scientific literature was analyzed, coast is higher than that in deeper areas further off- namely 106 peer reviewed articles, conference con- shore, where lower grid resolutions in the range of tributions and technical reports. 10m to 100m are sufficient for most applications.

20 ouerccluain sn OTP il val- yield IOWTOPO using calculations Volumetric hr rdcinaentsuf not are for production mapping chart from measurements the even areas, hy- the of contents what authorities the of drographic with edge achieve the to on possible be is would DBM Such Sea Baltic charts. a nautical in displayed morpho- details of level logical the or IOWTOPO of resolution isexpressed. place DBM specific of a estimate at an quality in interest half responses, than the more of in resolu- requirements, these coverage from and Apart tion Sea. Arkona and Baltic mentioned. those satis be physical be may generally whereas modeling circulation areas, and shallow oceanography very in needs high-resolution extremely for account plications ap- geotechnical and Archaeology requirements. igatvte r o talaindt ev com- a serve to aligned all at not are map- activities these ping However, companies. private and institu- tions research authorities, state including bathymetric data, producing parties other are there ities, author- hydrographic national the of responsibility used. is data DMU the on based are that ues have results. can modeling circulation This e.g. IOWTOPO. for of consequences versions signi out both smoothed in are Sea, North and trough Sea Baltic between narrow exchange but deep-water for deep important a namely area, sample sea the of Signi detail phology. of level enormous the an in shows increase data DMU the from derived of waters states. territorial Baltic the circum least most at for data exist better should or the similar of authorities, archives hydrographic the In beam 1988. single before hydrographic measurements on based mostly of is order the and on spacing This node 2000). a features al., model et (Nielsen bathymetry of Belts model the (TIN) Network Irregular Triangulated released Envi- a has National (DMU) Danish Institute Research The ronmental area Belts. an for Danish out the carried in was comparison sets a data DBM, different Sea of Baltic a for goals realistic detail. of lhuhmpigfrsft fnvgto sthe is navigation of safety for mapping Although of size cell a with grid spaced regularly A be might what of impression an given to order In the than higher far bar the raise needs These Scienti these within fall not do uses particular Only fi eerhi isdtwrsSouthern towards biased is research c 3% fi atmrhlgclfaue nthe in features morphological cant to fi dwt oe eouin than resolutions lower with ed 9% ’ oe hnwe h DBM the when than lower aaae.Sil nmany in Still, databases. fi in o uhalevel a such for cient fl o mor- oor fi cantly 50m 50m . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 ihabtyer n lvto oe,covering model, elevation and bathymetry a with es ag fapiain rmscienti from applications of range verse cesbefrms n sr eas bathymetric in- because users be end also most may for data accessible Existing needed. is mapping further activity quality and high missing, areas, are many data In bathymetry Sea. Baltic the avail- for DBMs able overview coarse the in or portrayed charts details nautical few relatively the sea beyond the far of shape the where suf tasks, not are rather resolution with detail sets low data common The ba- data: with thymetric problems common of also number study a and highlights Our planning resources. the marine as of such management needs, societal vital to the sea and the Bathymetry of study. morphology the of results the from Conclusions future. the in available being quality data tive produced all of data advantage taking these and Harmonizing activities archived. even not measure- are the ments cases some the In about environment. knowledge marine our improving of goal mon indtstsmlrt h B hw norcase our in shown DBM the to similar dataset on tion resolution a of at order coast the the to close areas shallow satis be could applications many coverage, cal enor- region mously. Baltic the in would research sets marine data stimulate quality that higher expect of can availability One the data. us- base on weak worked relatively being ing range are wide topics A and disciplines sets. of data available readily of extent extent geographical the scienti that indication of is An work data. this base in found the of potential the by habitat aspects. includes mapping which Action 2007), Sea (HELCOM, Baltic Plan HELCOM the instance for bathymetry data, resolution high on dependant largely are commitments international binding Politically ef or sea at environ- safety the ment, for consequences potential with sions for foundation optimal Insuf no are support. decision as used quently considerations. political and military to classi are data ocrigsailrslto n geographi- and resolution spatial Concerning Scienti fre- are data depth authorities, governmental At — ne aeu osdrto fterespec- the of consideration careful under fi fi eerhi fe togyin strongly often is research c tde sfeunl dutdt the to adjusted frequently is studies c eea ocuin a edrawn be may conclusions Several 10m fi da erti oecutisdue countries some in secret as ed — eetees oe resolu- lower a Nevertheless, . illa oipoe DBMs improved to lead will fi fl in diitaiework. administrative cient o r eeatfradi- a for relevant are oor — fe costly often fi fl in o many for cient o srelevant is oor fi fi research c in data cient fl uenced — deci- fi ed 21

Summary Summary: Mapping bathymetry study would still be a large leap forward compared ments and timing of Pleistocene glacial activity. to the present situation. How these details fit into the big picture of the en- Mapping the seafloor is important for much tire Arctic Ocean is subject of paper 5 (Jakobsson more than safety of navigation but a laborious and et al., 2010). expensive task. Therefore it appears self-evident The data presented were acquired with the that the use of all measurements produced should Kongsberg EM120 multibeam sonars and inte- be maximized to serve the needs of the end users grated SBP120 chirp sediment profilers on I/B in the best way possible. The potential DBM im- Oden in 2007 (Jakobsson et al., 2008b) and RRS provements are enormous; as are the benefits they James Clark Ross in 2006 (Dowdeswell, 2006). would have for society and research likewise. After Oden’s upgrade to the EM122 system, additional data from the area were acquired in 2009. The multibeam swaths and subbottom profiles Geophysical seaﬂoor mapping provides new insights cross several previously sampled coring sites, in- into the Arctic Ocean glacial history (Dowdeswell et al., cluding ODP sites 910 and 912 drilled during 2010) Leg 151. Being the only deepwater gateway into the Arctic A number of different glaciogenic landforms Ocean, the Fram Strait (Fig. 0.4) has through its were mapped in the study area. Linear features geological history played a central role for the Arc- of similar appearance to Mega Scale Glacial Lin- tic Ocean circulation and heat budget (Spielhagen eations (MSGL) exist on bathymetric highs shal- et al., 2004; Jakobsson et al., 2007). Its central lower than ca. 600m on the southern Yermak trough is roughly 150km wide and has a sill depth Plateau trending SSE–NNW and on the shelf north- of 2545m (Klenke and Schenke, 2002). The com- west off Spitsbergen trending ESE–WNW. They paratively shallow shelf areas on both sides of the are interpreted as traces of a coherent grounded Fram Strait have been subjected to drastic changes ice mass moving over the plateau in SSE or NNW during the Quaternary due to changing sea level direction. Furthermore, curvilinear features of and ice cover conditions. The Yermak Plateau varying length, width and relief are observed over northwest off Svalbard occupies a key position in almost the entire surveyed area at water depths this context, and its seafloor morphology and sed- shallower than 800m. These occur in two dis- iments hold details about the Quaternary Arctic tinct scales: (1) Large, several kilometers long, Ocean glaciation history as well as water and heat several hundred meters wide, between ca. 20m exchange with the North Atlantic. and 80m deep, and occuring in a depth range of Significant areas of the Yermak Plateau and 400m to 600m. (2) Generally less than 1km long, Northern Svalbard Margin have been mapped less than 100m wide, usually with less than 10m during recent years using high resolution multi- relief, and occuring at water depths shallower than beam echo sounders and acoustic subbottom 400m. Both types are interpreted as plowmarks profilers (Vogt et al., 1994; Kristoffersen et al., of large, deep-keeled icebergs. In some occasions, 2004). These mapping data are together charac- these features run parallel to each other, which is in- terizing the seafloor morphology and uppermost terpreted as either caused by multi-keeled icebergs ca. 30m to 100m of the sediment stratigraphy. A or icebergs trapped in thick, multi year sea ice. number of generally less than 15m long sediment Another mapped morphological feature is a large cores have as well been collected in the area. They moat, interpreted as a current overflow channel. provide a framework of the stratigraphy, together The mapped area located deeper than 800m has in with other previously acquired short cores and general a rather featureless seafloor seafloor mor- the long cores drilled on the Yermak Plateau dur- phology and is draped by conformable hemipelagic ing the Ocean Drilling Program (ODP) Leg 151 sediments. (Thiede et al., 1996). In this article, the available The sediment stratigraphy and chronology is be- high-resolution geophysical and geological data yond the main scope of this thesis, however, a brief are integrated to investigate the Quaternary glacial summary is required to place the mapped glacio- history of the Yermak Plateau and Northern Sval- genic landforms in a geological context. From the bard Margin. In particular, the spatial distribution acquired subbottom profiles three different acous- of glaciogenic seafloor landforms is analyzed in tic units can be differentiated. The first unit is detail, aiming at reconstructing ice extent, move- comprised of layered sediments draped on top of

22 in:C hkh odrad J orsJspRs;Y emkPaeu ahmti aafo IBCAO. from data Bathymetric Plateau. Yermak – YP Rise; Jesup Morris – MJR Borderland; Chukchi – CB tions: 0.4: Figure h ahmtyo h rtcOen ORG20 n 09si rcsmre ihrdlns Abbrevia- lines. red with marked tracks ship 2009 and 2007 LOMROG Ocean. Arctic the of bathymetry The 5 0 5 1000 750 500 250 0 Kilometers Amerasian Basin Lincoln Sea 6000 CB MJR 4000 Depth . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 / YP 2000 m Svalbard Eurasian Basin 0 23

Summary Summary: Mapping bathymetry an erosional surface. The second unit below the advance of the Saalian ice sheet over the Yermak erosional surfaces is characterized by poor acoustic Plateau was of relatively short duration. Another penetration and occurs at water depths shallower possible, and apparently the simplest, explanation than ca. 580m usually as the topmost layer, coin- for the observed features are giant deep-keeled ciding with the MSGL type bathymetric features. icebergs, possibly enclosed by multi-year sea ice, A third unit, comprised of acoustically transparent exiting the Arctic Ocean through the Fram Strait sediments with weak and discontinuous internal and drifting onto the Yermak Plateau from a NNW reflectors, is mapped on the Fram Strait side of the direction. This hypothesis is consistent with the Yermak Plateau crest and is interpreted as debris MIS 6 Arctic ice shelves proposed by (Jakobsson flows. There is evidence for two joining erosional et al., 2010, paper 5). The third acoustic unit surfaces on one profile, indicating that the plateau mentioned above and interpreted as downslope has been eroded more than once within the time debris flows could be explained by this NNW–SSE interval of the imaged sediments. movement. To chronologically constrain the acoustic strati- The probably non-erosive nature of the MSGL graphy, a number of sediment cores has been inves- would then be in contrast to morphology of the tigated from the area. This includes short gravity large iceberg plowmarks found on the Northern cores from various projects (up to 13m long) as Svalbard Margin, seemingly of similar origin. Ad- well as the cores from the three ODP sites 910–912 ditional mapping of areas closer to the coast is (Thiede et al., 1996). The base of Marine Isotope required to bring further clarification in this ques- Stage (MIS) 2 can be reliably correlated between tion (see section 0.4.4). the cores using petrophysical properties. There are As the iceberg plowmarks crosscut the MSGL less clear indications for the base of acoustically in several places, they are very likely of younger stratified sediments extending into MIS 5. This origin than the MSGL, the most likely age being suggests that the observed glacial lineations origi- Weichselian. The size of the plowmarks suggests nate from before the late Weichselian, most likely that they are caused by icebergs much larger than the Saalian, MIS 6. Underneath the lineations, an those found in the Arctic Ocean today. The most early or mid Pleistocene erosion surface is found, likely sources for icebergs of such size are fast flow- which probably marks an earlier advance of an ice ing glaciers from the Weichselian Eurasian ice cap sheet from Svalbard (Flower, 1997). in the area of the Barents Sea. In contrast to possi- The NNW–SSE trending glacial lineations may ble sources south of Svalbard, under this scenario, be explained by movement towards NNW or from multiple icebergs could also be connected by thick NNW; the seafloor morphology itself does not sea ice, explaining the parallel nature of many of undisputable indicate one particular direction. A the plowmarks. movement towards NNW could be explained with Based on seafloor morphological evidence, pos- the grounded Saalian ice sheet advancing from sible scenarios for the Quaternary glacial history Svalbard towards the central Arctic. Indications of the Yermak Plateau could be developed in this for such ice sheet movement are found closer to the study. How these scenarios fit into the large frame NW Spitsbergen coast in form of lineations and a of the entire Arctic Ocean is the subject of the MIS 2 grounding line parallel to the coast (Ottesen following paper. and Dowdeswell, 2009); however, the direction of these lineations is rotated by 45° relative to the An Arctic Ocean ice shelf reconstruction based in part lineations on the Yermak Plateau. on bathymetric data (Jakobsson et al., 2010) An argument against the lineations on the Yer- mak Plateau having their origin in the Saalian ice During several icebreaker expeditions to the Arctic sheet motion are the petrophysical properties of Ocean in the last years, bathymetric mapping data, the sediment found in the upper 19m of ODP high resolution sediment echo sounding profiles site 910 (O’Regan et al., 2010). The only slight and geological material in the form of sediment increase in consolidation in the upper sedimentary cores have been collected. This especially includes layers is in contrast to the corresponding param- material and data from the continental shelves and eters found below the erosional disconformity of other comparably shallow areas (depth <1100m) the early Pleistocene ice grounding event described infringing the central Arctic Ocean, but also on by Flower (1997). This would suggest that the the central Lomonosov Ridge, areas, which may

24 “ eefudo h eta oooo Ridge, Lomonosov central the on found were col- previously on based results published as well to down depth a at discovered were I/B with rtc h lwak niaeta h icebergs the that indicate plowmarks The Arctic. dif extremely were conditions ice sea the As 1970). Mercer, (e.g. addressed is shelve ice Arctic rs tdph hloe hnc.785m. ridge ca. the than on shallower found depths at were crest grounding Nevertheless, poor. ice is of quality signs data the area, this in mapped were Greenland of north Ridge monosov expeditions. the during 2009 and 2007 in collected the Plateau, on is pro- focus fi subbottom the and thesis (bathymetry data this geophysical of context the In pan a of hypothesis the and Quater- constrained, the during are shelves nary ice Arctic circum time- of and line extents the results, previous of sideration sea sediments. their and in phology activity glacial of signs show xeiini 05 ra hloe than shallower areas HOTRAX 2005, the in On expedition discussed. is shelves Arctic ice Quaternary Ocean of hypothesis the data, lected as Borderland, Chukchi the and Ridge monosov 2010) above. al., summarized et and (Dowdeswell 4 paper of detail subject the in are which mapped, were features phological in glacially of pattern plex echo sediment pro with sounding revisited previ- were several sites and coring surveyed, ous bathyme- was the areas large where of 4), try paper and see 0.3.4 details section (for Svalbard northeastern off Plateau present. between 6, period MIS glacial to ground- the constrained the i.e. be of therefore time could The event 5.5. ing MIS of age abundance an nannofossil gave using core the discon- in erosional formity prominent the the Dating above plowmarks. sediment the of one of centerline in the A taken was Strait. (LOMROG07-GC-10) Fram core the gravity towards moved Lomono- and southern Ridge the sov of direction the from came deepest the is iceberg grounding of plowmarks large Greenland, oooo ig f Greenland off Ridge Lomonosov e)fo h orsJspRs n h Yermak the and Rise Jesup Morris the from les) oehrwt bevtosfo h eta Lo- central the from observations with Together Yermak the on out carried was work Extensive of tip northern the off Rise Jesup Morris the On Lo- southern unsurveyed previously the of Parts con- under and material, new this of base the On Oden fi fi ’ dn fsc lca vdnei the in evidence glacial such of nding e.O h emkpaeuacom- a plateau Yermak the On les. utba cosudri 2007. in sounder echo multibeam s fl ecdsea uenced 130–200ka ” 1045m (LOMROG) fl fl o mor- oor o mor- oor 1000m which , before fi cult . ca apn rmdt olcint h s fDBMs of use the to collection data from mapping Ocean 0.3 hc r o ujce ogaileoin This erosion. glacial to subjected not are which ol euti ifrn urn atrsmore patterns current different in result would rtciesevsnthvn rw otesz of size the to grown having not shelves ice Arctic h lca rso atrsfudo h central the on found patterns erosion glacial The ya otwr xeso fteNrhAmerican North the of extension northward a particular- as shelves, ly ice Quaternary been have there 2009). al., Ja- et 2007; Adler al., 2008; et al., (Polyak et kobsson 6 MIS after have place to appears taken erosion visible all varia- However, depth tions. different and of features overlay glacial glaciogenic an the generation with Borderland, complex, Chukchi is the history In 5. before grounding MIS ice suggests Plateau Yermak the sea and data seismic lution during time some at Pleistocene. sheet the ice thinner ex- a the of prohibit istence necessarily not (2008). does Hughes this and However, Grosswald and (1977) al. et re and (1970) as Mercer Ocean, by Arctic suggested central the covering shelf ice thick dif it makes eedn nlclbtyercextremes. bathymetric local on dependant a and factor, strati another weaker be generally stress may wind climate colder surface a sea in Altered Strait. in Fram water be the Atlantic may restrict and to way halocline one lower would the Sea and Barents ice continents large surrounding by the shielded covering caps Ocean Arctic an into freshwater input Less analogs. Antarctic modern their growth. shelve ice in Atlantic warm any from away preferably somewhere far margin, shelf continental ice Eurasian smaller the a along of form ice- the deep-keeled in for bergs area source appearance a suggests Their rather Strait. Fram the continental towards American shelf the from movement gen- ice a with eral explained be cannot Ridge Lomonosov Arctic. central the of in form the highs in bathymetric basin uneroded Ocean Arctic stretching entire shelve however, the ice is, across Arctic There pan 6. a against MIS is evidence shelves in ice been the have of to extent likely largest The Sheet. Ice rmalti vdneoemycnld that conclude may one evidence this all From reso- high cores, sediment of integration The amAlni ae a lob h esnfor reason the be also may water Atlantic Warm fi utt ru o continuous, a for argue to cult fi aino h rtcOcean Arctic the of cation fl o opooyon morphology oor fi fl e yHughes by ned wrestricting ow fl wthrough ow 1000m 25

Summary Summary: Mapping bathymetry

Arctic Ocean circulation of deep water from the nisms of CBDW flow over the central Lomonosov Amerasian Basin in the Eurasian Basin (Björk et al., Ridge into the Amundsen Basin. 2010) Four oceanographic sections were measured during the expedition, two on the Amundsen Basin The central Arctic Ocean is comprised of two large flank of the Lomonosov Ridge north of Green- basin complexes, which are divided by the Lomo- land, and two on the north and east flanks of the nosov Ridge (Fig. 0.4): The Eurasian Basin be- Morris Jesup Rise. In the latter region, extreme tween the margin of the Barents and Kara Seas and bathymetric gradients were surveyed, which are the Lomonosov Ridge, and the Amerasian Basin considered to have a strong influence on the cur- confined by the Canadian and Alaskan continental rent patterns. A few additional CTD profiles from shelves, the eastern Siberian continental margin the HOTRAX/Beringia expedition in 2005 (Darby and the Lomonosov Ridge. The Gakkel Ridge et al., 2005) are included in this study. splits the Eurasian Basin into the Nansen Basin (to- In the oceanographic data, CBDW can clearly wards Siberia) and the Amundsen Basin (towards be identified around a depth of 2000m on all four the Lomonosov Ridge). The Alpha-Mendeleev sections. The corresponding salinity maximum Ridge divides the Amerasian Basin into the Canada and temperature anomaly is strongest close to the Basin and the Amundsen Basin (Fig. 0.4). As men- Lomonosov Ridge and decreases as one moves into tioned previously, the only deep water passage the Amundsen Basin. There are only minor lateral connecting the Arctic Ocean to other parts of the differences between the three sections on the Lo- World ocean is the Fram Strait between Greenland monosov Ridge flank and the northward section and Svalbard. Seafloor physiography is one of on the Morris Jesup Rise. These measurements the most critical boundary conditions influencing suggest that CBDW passing the Lomonosov Ridge large-scale ocean current flows. This paper shows through the Intra Basin close to the North Pole how influential bathymetry on different scales is (Björk et al., 2007) flows along the ridge towards for the present Arctic Ocean circulation pattern. Greenland, where it turns eastward towards the Several distinct water masses are important for Morris Jesup Rise. This flow is closely confined to large-scale oceanographic processes in the Arc- the respective slopes (Fig. 9 on page 133). Above tic Ocean. Water originating from the Atlantic, the mentioned T -S-maximum, in the depth interval through inflow via the Fram Strait and across between 600m and 1200m, Canada Basin water the Barents Sea, contributes to water masses in characteristics can be observed in the Amundsen the Arctic Ocean from near the sea surface to Basin close to the Lomonosov Ridge, forming a approximately 2000m water depth (Björk et al., frontal structure between the ridge crest and the 2007). This gives rise to a prominent Atlantic Amundsen Basin. A similar structure can be found warm (above 0 ◦C) core between about 150m and in the northward section from the Morris Jesup 800m that flows along the continental margins Rise. and major ridges all around the Arctic Ocean. Be- The fourth oceanographic section acquired dur- low this warm core in the Eurasian Basin lies the ing LOMROG 2007 is comprised of CTD profiles colder and more saline Eurasian Basin Deep Water from the Morris Jesup Rise eastward to the Gakkel (EBDW). Its counterpart on the Amerasian side of Ridge. The eastern flank of the Morris Jesup Rise the Lomonosov Ridge is the Canada Basin Deep features an extremely steep slope at ca. 35°, which Water (CBDW), which is warmer and more saline sharply turns around the northeastern tip of the than EBDW. CBDW and EBDW also differ in their Morris Jesup Rise, into its northern slope with a chemical properties. All these water masses inter- gradient of ca. 17°. From the bathymetry data, act and spread far away from the regions where the radius of the corner is estimated to be around their properties have been established. 400m. Altogether; the northeastern part of the The flow of CBDW in the Amundsen Basin and Morris Jesup Rise is a topographically extreme towards the Fram Strait is here investigated us- feature (see Fig. 5 on page 130), which can be exing oceanographic measurements and samples to- pected to have a strong influence on the regional gether with multibeam bathymetric mapping data, current pattern. acquired during the LOMROG 2007 expedition. At this eastward section from the Morris Jesup It may be seen as a continuation of the work of Rise, a different situation than in the other three Björk et al. (2007), analyzing in detail the mecha- sections can be observed. On the slope, the CBDW

26 eto h emkPlateau. Yermak the of west between section this in found be Basin also Makarov can of water structure frontal The wards. stesuc aafrtebtyer remains bathymetry the for data source the As h pro The hog h iecanla h reln ieend side Greenland the at channel wide the through northward turns which Strait, Fram the in ca. isobath the along steering topographic Basin be Amundsen could the the in into CBDW likely of for is re-circulation possibility Rise Another Jesup context. bathymetric Morris given the northeast- of the at tip CBDW ern the of detachment that 250m south- turn sharp the at slope Rise the Jesup from Morris detached partly and downwards placed Ridge. Lomonosov the the on of found slope situation the resembles Rise. closely slope Jesup Morris the of slope northern the on ca. occurs signature ufc sls elkonta h oorpyof topography earth the the than of known parts well Hall, less large is 2000; of surface al., shape the et (Vogt and 2006) surveyed have been areas, coastal yet of not also of but parts ocean, World large the Still, states. ad- coastal the of for ministrations important also climate is of bathymetry consequences hazards change, the mitigate or to tsunamis or as ways, such possible best use the and in environment it In marine the more. manage many to and order system, climate the the of in role ocean the resources, offshore nature, the marine concerning questions investigating con- when regional text a provides marine often it the where in geosciences, role important an plays Bathymetry 0.4 Sea. Lincoln western the from route direct this con could sec- passage oceanographic this an across Only tion assess. to easy region not this is in IBCAO of reliability the undisclosed, only of 2008a) depth al., a et displays (Jakobsson IBCAO of version most recent the 2001), (Naryshkin, by authorities published Russian contours bathymetric on based than ever, deeper is passage to the According map, (1986). this al. bathymetric et the Perry on by published based map (1995), al. et Jones suggested previously by was Ridge Lomonosov the of The dis- partly is body CBDW the that suggests This fi mCD neigteAude ai on Basin Amundsen the entering CBDW rm Discussion and fl wo nemdaeCnda ai water Basin Canadian intermediate of ow fi efo h bsa li eet the beneath plain abyssal the from le 1500m og cln nlssshows analysis scaling rough A . 0mt 300m to 200m 1200m fi al ueotor out rule nally o hspassage. this for 1500m eprthan deeper 3000m How- . iepeduedrn h 90,todevelop- two 1990s, the during use widespread data heterogeneous large, of gridding the as well Uie ain,18) nldn t rils76ff. Articles its including 1982), Nations, (United igadtepreto foenmpigoutside mapping ocean of map- perception ocean the on and effect ping enormous an had have ments hydrographic the authorities. and providers parti- data importance for great cularly of it even consider knowledge, before, we studied our though been To never has 3. question paper this in inves- detail was in how, and tigated for, data used depth being such eventually what is question The 2). (paper sets as 1) (paper metadata corresponding and data ing and developed re were methods (DBM) Models Bathyme- tric Digital of compilation the Concerning hypotheses. oceanographic and geological Ocean 4 expeditions, papers of the number to a car- leading after was and data during out sounding ried such for pro- post typical as cessing well as sounders echo state-of-the-art the 1999). al., et (Smith mars planet the example for hmtyo casadsa sdslydbsdon based displayed is ba- seas Earth, and Google oceans of of part thymetry As to mapping public. ocean general of the world the opening in enormous had success has 2009 in The Ocean Google again: of launch once community stimulated mapping event ocean recent the a Nations, United claims the 76 to Article submitting and efforts mapping not 76. probably Article would without thesis happened this have of 5 paper carried for mapping out an the of give To parts 2001). important al., impact example, et major (Vogt a research had marine has on This EEZs. the present of the borders beyond claims extending shelf for continental submissions their their states on coastal working as are multiplied, been the have mapping ocean on deep spent resources gen- The the and public. makers eral policy of attention and the have to sea resources come unknown deep largely the but potential 76, its Article to rati have Due countries UNCLOS. 160 ar- about these today, in Until rights eas. associated the and (EEZ), Economic Zones Exclusive miles nautical 200 the beyond 1994 de in legally force into came (UNCLOS) Sea the of community. scientific the fi ic utba cosudr aeto came sounders echo multibeam Since from aspects of number a on focuses thesis This smr n oecutisare countries more and more As Law the on Convention Nations United The e,nml o h obndaayi fsound- of analysis combined the for namely ned, fi l foenmpig aacleto with collection Data mapping. ocean of eld fi igteetn fcnietlshelves continental of extent the ning – ,wihda ihArctic with deal which 6, fi aiigtheir nalizing . Discussion 0.4 fi ed 27

Summary Summary: Mapping bathymetry public domain DBMs, including GEBCO (GEBCO, areas even in the North Atlantic soundings are 2008) and IBCAO (Jakobsson et al., 2008a). This sparse. This source data makes the North Atlantic highlights the importance of not only collecting an ideal test bed for developments regarding DBM new bathymetric data in regions not sufficiently compilations. surveyed, but also the necessity to integrate the At the time paper 1 was published, no DBM available measurements into data sets readily avail- existed which incorporated the multibeam sur- able and useful for different applications. veys carried out in the North Atlantic for research purposes (Carbotte et al., 2004) and UNCLOS 0.4.1 Tools for DBM compilations related surveying (Gardner et al., 2006). There- fore, working towards compiling a new North The work on IBCAO (Macnab and Jakobsson, Atlantic DBM was an exciting goal. This situation 2000) highlighted a number of methodology re- has changed since the GEBCO_08 grid was related topics relevant for DBM compilations: The leased (GEBCO, 2008). In GEBCO_08, predicted importance of metadata for thorough data ana- topography derived from satellite altimetry mea- lysis, the value of GIS technology for handling surements are combined with a comprehensive bathymetric data, the power of 3D visualization set of sounding data, including many multibeam to find problems in the source data and the need surveys. Still, with the comparatively abundant of efficient data storage and access for the hetero- bathymetric data, the North Atlantic has the poten- geneous data used for DBM compilations. tial for a purely sounding based DBM, following Due to the vastness of the oceans and the costs the example of IBCAO. for multibeam mapping, to date only about 10% Our solution adds complexity to the storage of of the World ocean is mapped with high resolution sounding data, compared to just handling simple and accurate precision technology (Hall, 2006). (x, y,z) records. Nevertheless, the extra work in- Therefore, historic measurements are still vital for volved in the preparation of metadata pays back regional and global DBM compilations. They com- when problems in a compiled DBM have to be prise to a large extent single beam transects col- traced down to their roots. lected during the 1970s (Smith, 1993). The result is a source data set with greatly varying density and 0.4.2 Gridding of heterogeneous bathymetric accuracy, both for the positioning of each sound- data sets ing and for its depth value. Other information, such as the source of the data or their original pur- For the gridding of topographic or bathymetric pose, may be useful in the compilation process as data, a number of different approaches have been well. Ideally, these metadata should be considered developed and used. A number of studies have in the compilation process, to obtain a realistic been published comparing different gridding meth- picture of the quality of the final DBM. ods (Franke, 1982; Dubrule, 1984; Li and Götze, At many hydrographic authorities, the use of 1999; Katzil and Doytsher, 2000; Yang et al., 2004; relational databases and GIS for storing and hand- Reuter et al., 2007), highlighting different advan- ling bathymetric data is nowadays standard. How- tages and disadvantages for the methods in dif- ever, the needs for producing nautical charts are ferent application scenarios. For example Reuter different from those for DBM compilation. Our so- et al. (2007) concludes that in the case of Shut- lution, built around data warehousing techniques tle Radar Topography Mission data (Farr et al., adapted from large commercial enterprises (cf. 2007), using four different algorithms would be Kimball and Ross, 2002), is designed to suit the ideal for interpolating data voids of varying size latter. and in different terrains. For testing this data model and processing en- Almost all interpolation algorithms estimate the vironment, a region of the North Atlantic Ocean value of a grid node from its surrounding data was chosen. Of all oceans, the North Atlantic is points using weighted averaging; the difference arguably best mapped. Numerous single beam of the methods being mostly how the weights are tracks, and some extensive multibeam surveys determined. cover most areas of the North Atlantic with a com- Three groups of methods are routinely used to paratively high data density. However, the data grid terrain data, namely nearest neighbor or in- is of varying quality and resolution, and in some versely distance weighted moving averages (e.g.

28 ihKiigrpeettesaitclyms likely most statistically the represent Kriging with obtaining or details losing without sa nta tp aiga ftesuc data source the of variogram a step, initial an As og n conl 98 .14.Ti a be may This 114). p. (Bur- 1998, node McDonnel, grid and each rough to point data the source of closest value the assigning interpolation, neighbor areas. constrained results data good poorly yield in as well as incor- sub-sampling should porate compilation DBM for suitable ods an in of sounding area single a sound- to 100 kilometer square of per order ings the on heteroge- ranging density, extremely neous their of because unusual are DBM for typical size the of compilations. sets data source applied to when demanding computationally is ing an bene as potential with seen alternative frequently A is 2002). Kriging, al., method, et fourth Pajarola (e.g. Irregu- (TIN) Triangulated Networks lar and 2000) Macnab (e.g. Jakobsson, splines and bicubic 2001), al., et Seifert ehd r elsie o nepltn sparse interpolating for The suited surface. well the are of methods point each for uncer- estimate an tainty include usually results Kriging surface. obtained Grids variogram. the on of based properties are the weights interpolation particularly The data, range. the its in na- correlation the spatial of about ture details reveals which computed, is 1963). (Matheron, data source the of statistical properties from determined are weights polation grid. the in facets lattice regular a into transformed be easily cannot useful are ef models e.g. TIN for nodes. other not any do the contain triangle and each possible around as circles uniform circumscribed as in- are TIN the angles a where ternal tesselation, of triangular edges a and form nodes model The an way. points optimized data spaced irregularly connecting tures voids. data in interpolation neighbor problems near the of reduces and sub-sampling source and dense data for suitable particularly is interpolation weighted distance Inversely surface. smooth result- value, same in the ing assigned adjacent be many may sparse, nodes is grid data source source the the in If present data. are outliers if problematic ef very computed rgn sacaso ehd,weeteinter- the where methods, of class a is Kriging struc- data are 1934) (Delaunay, models TIN nearest is method interpolation simplest The compilations DBM for used sets data source The fl taeswt tp nbtenisedo a of instead between in steps with areas at 1000km fi in iulzto rcnorn,but contouring, or visualization cient 2 osqety rdigmeth- gridding Consequently, . fi inl,btterslscnbe can results the but ciently, fi s oee,Krig- However, ts. fl t triangular at, ihsas oredt r rde tmr appro- more at gridded are data source sparse with c.Bo,2001). Boor, (cf. eg akgopo rdigo h EC SCDB, GEBCO the of gridding on group Task (e.g. hm ihicesn eso,tecraueo the of curvature the tension, increasing With and them. equations the to an factor developing tension a adding by geoscienti for especially terpolation, undershooting arti and of over- form so-called the extremes, in cial artifacts to lead constraint, can however, curvature poor minimum with The areas support. in data even pleasing visually are they con- not any do tain splines bicubic because to Mostly analog points. is plate surface metal This a curvature. pos- total lowest sible the and derivatives second continuous fi map- ocean applications. to ping closer Kriging Hössjer, brought and have Hartman 2008) 2006; al., et (Furrer developments recent Kriging However, of compilations. use DBM the for prohibited numbers has large which with points, sets of data source for demands high computational are the but sets, data source fsakdslnsgidn shge computational drawback higher is The gridding splines grid. stacked the of of areas other in artifacts prominent increasingly gridded without resolutions be high may at covered areas data the source time, same densely the most At tracks. ship arti- along reduced facts in resulting resolutions, lower priate, Areas ways: two in superior results yields manner.method simple a in place certain a the of assess to quality used data be can interpolated information the This from surface. apart re- place effective each the at of grid solution splines a stacked produce be the also to size, may method cell chosen variable not with is grid output a the If (see tension 0.3.3). in section splines of shortcomings typical to tension in splines tension, in splines al., et Jakobsson 2000; al., 2008a). al., et et Zuber Jakobsson 1997; 1998; Smith, and Sandwell 1997; success great with sets data terrain many of lation tension in splines method, cited Their frequently artifacts. undershooting and sup- over- points, pressing data source the around focuses surface stesraetruhaldt onswihhas which points data all through surface the ts mt n esl(90 mrvdsln in- spline improved (1990) Wessel and Smith 1974) (Briggs, splines bicubic with Interpolation etdo eeoeeu ahmti aa our data, bathymetric heterogeneous on Tested upon building method gridding improved Our fl taes neswratdb h data, the by warranted unless areas, at fl fi xdtruhanme of number a through exed iedfeec loih osolve to algorithm difference nite ” ” fesavnae ihregard with advantages offers , “ a enue o h interpo- the for used been has , tce otnoscurvature continuous stacked “ otnoscurvature continuous . Discussion 0.4 fi aasets, data c fi xed 29 fi -

Summary Summary: Mapping bathymetry demands due to the repeated gridding of the same implementing these goals, legal relicts from Cold source data set at various resolutions. However, War times are severe hinders for carrying out the we believe that these higher computational costs required work. Habitat mapping is an example re- are not prohibitive for typical ocean mapping ap- quiring high-resolution bathymetric data in areas plications. close to the coast. Yet these are the areas where most restrictions apply. The work with secret data 0.4.3 The use of bathymetric data for research is cumbersome, and obtaining permission to carry and other purposes out surveying incorporates severe hurdles. We hope that the legal framework will change in the To our knowledge no previous systematic analy- future, to the benefit of research and the advantage sis has been published investigating exactly what of the general public. Maybe our findings serve bathymetric data are used for, whether they are suf- this goal by contributing some arguments to the ficient for the respective applications, what prob- discussion. lems the end users of bathymetric data are confronted with, and what specific needs they have. 0.4.4 Quaternary glaciation history of the Arctic Ocean mapping scientists or hydrographic author- Ocean ities should, as data providers, ideally take such aspects into consideration when preparing bathy- Floating sea ice or ice shelves only leave indirect metric data for general use, so that their usefulness geological evidence of their existence, in the form can be optimized. of ice-rafted debris (IRD). Grounded ice, on the In shallow seas, close to the coast or in the terri- other hand, can be accounted for very distinct torial waters of a certain state, most bathymetric traces on the seafloor. Such marine glaciogenic data is measured primarily for safety of navigation landforms include plowmarks from iceberg keels and the production of nautical charts. The respon- and Mega Scale Glacial Lineations (MSGL), form- sibility for chart production lies at national hydro- ing at the contact between a grounded ice sheet and graphic authorities, often divisions of the navies. the seafloor. The time of the corresponding glacial In a number of countries, including Sweden, the event may be constrained by dating the bottom of detailed sounding data charts are based on, are the sedimentary unit up-hole of the erosional sur- classified as secret information, which results in face, e.g. with 14C radiocarbon dates in sediment nautical chart soundings being the best publically cores. By mapping the type as well as the spatial available portrayal of bathymetry. However, chart and temporal distribution of ice grounding events, soundings are not ideal for many applications in re- the extent of large ice masses may be constrained. search, administration, spatial planning or manag- The similarity of the northern and southern ing the marine environment and resources, mostly high latitudes inspired Mercer (1970) to propose because chart soundings are sparse, non-uniformly a pan Arctic Ocean ice shelf during the Quater- spaced and selected with a bias towards shoals. nary glaciations. Both the Arctic Ocean and the Our study shows the great potential high-quality Southern Ocean around Antarctica have large con- bathymetric data have for a wide range of appli- tinental shelves, but today no ice sheet exists in cations. In general, we believe that a modern soci- the Arctic with a size analog to the West Antarctic ety, including its research community, profits from Ice Sheet, the source area for most of the large freely available base geodata. In the case of bathy- Antarctic ice shelves (Bentley, 1987). Hughes et al. metry, significant resources are needed to acquire (1977) picked up on Mercer’s idea and proposed such data. Still, because of the necessity of accu- a 1000m thick ice floating shelf covering the en- rate nautical charts, these resources are spent in tire Arctic Region during the Last Glacial Maxi- most coastal states. Our review shows that these mum (LGM) together with adjacent grounded ice acquired data may benefit a much broader range shelves and the Quaternary Eurasian and North of applications than only safety of navigation. American ice sheets. Later, Grosswald and Hughes Sweden is often seen at the forefront of environ- (2008, reprint from 1999) concluded that such an mental care and a sustainable use of the marine ice shelf repeatedly existed over the course of the resources. Legally binding manifestations of this Quaternary glacials. Similar to our studies (pa- include e.g. signing the HELCOM Baltic Sea Ac- pers 4 and 5), they based their conclusions to a tion Plan (HELCOM, 2007). When it comes to large extent on evidence from marine glaciogenic

30 ekrta oa uigcle lmt periods climate colder during today than weaker rtcOen nestimated An Ocean. Arctic oeSedu equals Sverdrup (one Hl n oe,2006). Soden, and (Held probably was it however, 2007); al., et (Jakobsson 1045m iul ital napd u otesvr ice severe the to due unmapped, virtually viously eu ie twtrdph between depths water at Rise, Jesup e ass(odseladJfre,21) This 2011). Jeffries, and (Dowdeswell masses lo- ter in in ones the tiny from from well-hidden apart cations Arctic, the in shelves ice At therein). heat references this and present, 2010, 2010; al., al., et et Wåhlin Jenkins 2007; glaciogenic al., et large (Nitsche through troughs locally only reaches coast and shelves the continental the of parts Antarc- deeper water in deep situation circum-polar present where the tica, This to 2004). contrast al., in et is (Maslowski basins Ocean tic ca. between anti depths an than at warmer forming water of Sea, circulation Barents clockwise and shallow Strait the Fram the over through Arctic the enters ter the into Atlantic North the from heat of amounts Ocean. Arctic the of areas several in landforms codnl slkl ohv apndi I 6. MIS in happened have to likely which the is event, of accordingly grounding onset the plow- the for after two date sedimentation the 5.5 of MIS an larger yields the marks of recovered bottom core the sediment from a Strait of Fram Dating the them. caused towards south- Ridge the Lomonosov from direction ern a in moving indicates icebergs plowmarks that semi-parallel direc- two The the Ocean. of Arctic tion the in scours iceberg of Morris the on discovered were plowmarks iceberg icebreaker nuclear Russian icebreaker Swedish the these of events. timing glacial the constraining evidence, published by this particularly to adds study al., Our et Kristoffersen 2004). 1994; al., et (Vogt for ice evidence grounded presented Yermak studies the previous On plateau, area. this in prevailing conditions pre- was Rise Jesup Morris The analyzed cores. and sediment data (chirp) sounding bathymetry, echo sediment swath This high-resolution include Borderland. Chukchi data Yer- the the and Rise, Plateau Jesup mak Morris the from particular in ages Miocene since existed has pattern circulation uigteLMO 07epdto with expedition 2007 LOMROG the During data, geophysical new on based are studies Our signi transports belt conveyor global The hs r h eps published deepest the are These . fl xpeet h omto of formation the prevents ux 200m 1km Oden 3 0LtPobedy Let 50 s to fl -1 fl wof ow upre ythe by supported fAlni wa- Atlantic of ) ec fteewa- these of uence 600m fl 1000m S o4Sv to 3Sv ossome oods nalArc- all in fi ndings large , fi cant 0 and ◦ C a eotdfrteSbra n fteLomo- the of end Siberian the for reported was Yermak the of part southern the on out carried was fe u td a ulse,frhrmapping further published, was study our After Jkbsne l,20) lo oMG ol be could MSGL no Also, 2008). al., et (Jakobsson 1000m r ptbre,apoietgonigln exists line grounding northwest- prominent the of a of coast Spitzbergen, ern the favor Off in (1) arguments hypothesis. explana- second good simpler are and there intuitive tion, more a like look Strait. Fram the across towards north Plateau the Yermak from the drifting sheets ice frag- of and ments icebergs other deep-keeled The large, Plateau. is Yermak possibility the of crest the across and Svalbard covering sheet The tures. fea- morphological seabed glaciogenic observed the for time likely most events. the glacial as these 6 MIS suggest cores pro sonar chirp sea high-resolution of Integration sites. coring chirp as pro well sonar as character, non-erosive curvilinear of and features plowmarks iceberg MSGL, to ilar sim- landforms revealing bathymetry, swath cludes with mapped I/B been have areas extensive Margin, o osbe lhuhatinriesefmyhave may shelf existed. ice thinner a although possible, not a glaciations, Quaternary during level sea lower these surveyed on the the below in lies Rise which Jesup area, Morris the on found of depth ca. at a Ridge and Lomonosov the ca. for 1999), of al., depth et a at Ridge nosov evidence such of absence The traces mapping activity. as glacial shelf ice of to thick a important of equally theory least the test at be may depths and Plateau. Yermak ice the an onto for Svalbard indications show re- not Preliminary do 2010). sults al., et (Noormets Plateau 1997). (Flower, area the in observed events erosive indeed earlier and for sheet, ice grounded happen a to expected under consolidation the show not features do like MSGL the below sedi- from the recovered ment of properties petrophysical Dowdeswell, The and (2) 2009). (Ottesen Svalbard 2) on (MIS Weichselian sheet Late ice the be to appears what of lhuhthe Although explain may scenarios different principally Two Svalbard Northern and Plateau Yermak the On erhn o nitre ra tciia places critical at areas undisturbed for Searching Oden hc c hl oeigteetr rtcis Arctic entire the covering shelf ice thick fi fi dnsadacutn o h ca. the for accounting and ndings n RRS and fi e,sm fte evstn previous re-visiting them of some les, s cnroi ae nagone ice grounded a on based is scenario rst 890m fi s cnromyat may scenario rst ae lr Ross Clark James n h dnSu at Spur Oden the and 940m fl fl wn northward owing 940m fi o morphology, oor e n sediment and les sbt.Based isobath. . Discussion 0.4 fi (Tsoukalas s glimpse rst hsin- This . fl wfrom ow 100m 912m 84° 31 N

Summary Summary: Mapping bathymetry

To constrain the possibility of a thinner coherent circulating into the Amundsen Basin or flowing ice shelf, shallower areas exist on the central Lo- towards Fram Strait and North Atlantic. If the re- monosov Ridge, which have not yet been mapped circulation of CBDW into the Amundsen Basin is in high resolution. The shallowest point on the significant, deep water eddies would be expected Central Lomonosov Ridge, at ca. 86°N towards and have at least once been observed (Schauer Siberia, reaches a depth of ca. 620m. That is, if the et al., 2002). Because of the severe ice conditions base data for IBCAO in that area, submarine mea- on the southern Lomonosov Ridge, oceanographic surements and digitized contours from a Russian measurements across the above mentioned channel chart, are correct. between Amundsen Basin and Lincoln Sea could From our new findings as well as older evidence not be carried out during LOMROG 2007. from various locations in the Arctic Ocean, large During the second LOMROG expedition in ice shelves may have existed in the Arctic during 2009, a different group carried out additional CTD Quaternary times, most likely during the Saalian measurements in the Amundsen Basin and found (MIS 6). preliminary indications for a deep eddy (S. Olsen, Floating ice shelves are virtually impossible to pers. comm.). They also carried out another CTD distinguish from a perennial sea ice cover with measurement close to the saddle point of the deep- the toolkit of geology. Therefore, without e.g. re- est channel from the Makarov Basin into the Intra liable modeling results, the extent of such paleo Basin on the Lomonosov Ridge, confirming the ice shelves remains speculative. However, there is persistence of the overflow found by Björk et al. strong evidence against a pan Arctic ice shelf in (2007) four years earlier (S. Olsen, pers. comm.). the form of undisturbed seafloor in critical regions The reliability of IBCAO in the area of the Green- and water depths. Ice shelves can only grow fed land end of the Lomonosov Ridge remains an by adequate source areas on the continents. Under open question. Here, IBCAO is almost exclu- this consideration, bands of ice shelves are most sively based on a 1:2500000 scale contour map by likely to have formed along the Canadian Arctic the Russian Federation’s Department of Naviga- coast as well as on the Siberian continental shelf, tion and Oceanography (DNO, Naryshkin, 2001), fed by the Eurasian and North Americal Saalian for which the source data are still undisclosed ice sheets. (Fig. 0.5). The only other data source contributing to IBCAO in this area are pre-1992 U.S. and 0.4.5 The importance of bathymetry for ocean U.K. submarine measurements, which are prone circulation to high positioning errors (Jung et al., 2002). The DNO map is very detailed in some places, but Our article builds upon earlier work by Björk et al. seems highly generalized in others, including the (2007), who presented a new bathymetric model mentioned channel into the Lincoln Sea. of the central Lomonosov Ridge and used it to A brief comparison of these contour data with investigate the flow of Canada Basin Deep Water multibeam measurements from LOMROG 2009 (CBDW) over the central Lomonosov Ridge into (Fig. 0.5) reveals only relatively small errors in the Amundsen Basin. Because of the route of the the contour map. However, this comparison is multidisciplinary HOTRAX expedition in 2005, strictly only valid in an area further north, where the circulation of CBDW along the Lomonosov the contour map is relatively detailed. The con- Ridge in the Amundsen Basin could not be inves- tinued Danish Article 76 related surveying work tigated further based on measurements from that may help in answering these questions. Due to expedition. Other possibilities for CBDW crossing the challenges of reaching this area with surface the Lomonosov Ridge, such as through the channel vessels, this work is now mostly carried out from between the Lomonosov Ridge and north Green- ice camps during spring. land (Jones et al., 1995) remained hypothetic. The oceanographic measurements on the LOMROG 2007 expedition show that CBDW 0.5 Conclusions closely follows the Lomonosov Ridge and northern Greenland margin in an anti-clockwise circula- In this thesis a range of ocean mapping related top- tion and that the bathymetry of the Morris Jesup ics was investigated, spanning from the acquisition Rise likely has a strong influence on CBDW re- of echo sounding data over the data processing

32 Nrskn 01;Ylo rcs–LMO xeiin;rdtak SU umrn ahmtymeasurements. bathymetry submarine US/UK – tracks red expeditions; LOMROG – tracks Yellow 2001); (Naryshkin, ttesdl on ftecanlbtentewsenLnonSaadMri eu ieICOi xlsvl based exclusively is IBCAO Rise Jesup Morris and Sea Lincoln western the between channel the of point saddle the At htteDOcnor a ecniee eibea es nta ra vncoe oteNrhPl ntsonin shown (not Pole North the reproduced to adequately closer was contours. Even bathymetry DNO of the area. trend by general that the in but errors, shows least revealed north at measurements LOMROG further reliable the soundings considered detail), submarine be with can comparison contours A DNO map. the DNO that the from contours sparse relatively the on 0.5: Figure otu intersection Contour : sounding Submarine : eeto fbtyercdt nteLmnsvRdeo reln:Wiecnor iiie N map DNO digitized – contours White Greenland: oﬀ Ridge Lomonosov the on data bathymetric of Selection

60°W 80°W 82°N Lincoln Sea

400

1200 1200 1400 1800

1600

1000 600 84°N

40°W 400

800

L o m o n o s o v R id g e 2800 Morris Jesup Rise

20°W

4000

. Conclusions 0.5

88°N 86°N 0° 33

Summary Summary: Mapping bathymetry involved to obtain bathymetric data sets, which From paper 3 eventually may be used for various applications. • We investigated in detail how bathymetric data The use of bathymetric data was a major focus of are used for purposes other than safety of navi- this thesis, including both a general investigation gation, and problems the users are confronted of data use and three applied articles studying ma- with. Our review focuses on the Baltic Sea and rine quaternary geology, paleoclimate questions applications in the research community and at and physical oceanography in the Arctic Ocean. public authorities, based on a questionnaire sur- The following conclusions may be drawn from vey and an in-depth literature review. these studies. • To our knowledge this is the first such study published worldwide. This is surprising, since From paper 1 many coastal states spend a lot of resources on hydrographic surveying, and our study shows • The combination of a GIS and a spatial rela- that bathymetric data in general, and specifi- tional database is a tool for DBM compilation, cally data produced for safety of navigation, are capable of enormous flexibility in data storage useful for a much wider range of applications and powerful analysis and data visualization than the primary use the data were anticipated possibilities. We developed a solution specifi- for. cally designed with DBM compilations in mind, • Based on our findings it may be easier for data and focusing around important metadata. providers, both in the scientific community and • Metadata, i.e. data describing data, are vital in- at the hydrographic authorities, to provide data formation when dealing with the heterogeneities with specifications closer to the needs of the end of the World ocean echo sounding database built users. over more than half a century. A data model was developed implementing important metadata to From paper 4 be readily accessible. The metadata that is com- • On the Yermak Plateau and northern Svalbard monly available with sounding are often less Margin, new acoustic mapping data, swath ba- comprehensive than desired, sometimes flawed thymetry and subbottom chirp sonar profiles, and come in a variety of formats. To bring meta- have been acquired. In this area, marine glacio- data into a coherent structure therefore involves genic landforms from glaciation events during a lot of manual work that is difficult to auto- the Quaternary have been observed. Our new mate. data adds important spatial and temporal constraints to the existing database. From paper 2 • Different glaciogenic landforms were systemati- cally analyzed with regard to their shapes and • Gridding sounding data for DBMs poses chal- spatial distribution. The data were integrated lenges due to the extreme differences in source with previously acquired short and long cores, data coverage. Few gridding methods exist that to constrain the timing of the glacial events. Pos- are capable of subsampling and interpolating sible scenarios for the generation of the features large such data sets. The application of a com- were developed. Our favored solution includes monly used interpolation method, continuous giant icebergs or remnants of ice shelves drifting curvature splines in tension, was improved in through the Fram Strait during MIS 6. our work. • Our method, stacked continuous curvature From paper 5 splines in tension, takes local data density into • Evidence of glacial events in the form of marine account to determine a suitable gridding reso- glaciogenic landforms has previously been col- lution for each place. This allows for a gener- lected in a number of places in the Arctic Ocean. ally higher resolution in areas with dense source We contributed additional mapping data to the data, while minimizing gridding artifacts in ar- archive, in form of swath sounding data and sub- eas where source data are sparse. bottom chirp sonar profiles from the Yermak • In a comparison with two closely related grid- Plateau (paper 5), the Morris Jesup Rise and the ding methods, our method yields significantly southern Lomonosov Ridge off Greenland. improved results. • Integrating all existing of seafloor mapping evi-

34 hr ahmtyadoenmpigi h main the is mapping ocean and bathymetry where rmppr6 paper From ehd rt tr rmsrthwt regional a with project. scratch compilation from start gridding to improved or our method, with DBM existing to an are grid Possibilities involved. sets data speci large-scale challenges the possi- give under and drawbacks would capabilities ble compilation their of DBM proof large ultimate the a in 2 and brie here. may discussed possibilities be some work, the of focus the For anticipated. be the may thesis, on this in building covered work aspects further different the of all In 0.6 • • • • ae spr na non rjc fthe of project ongoing an on part is 3 Paper 1 papers in developed methods the Applying ihdtsfo eietcrs h hypothesis the cores, sediment from dates with rtcOeni h uainBsncudbe could Basin Eurasian the in Ocean Arctic large related with Siberia, possibly and Arctic nipratipc ncruainpatterns. circulation on impact important have an may even features that bathymetric shows small study relatively our and limited, very area is critical the from The available data question. bathymetric open an remains Greenland off Eurasian The the into Basin. re-circulate slope probably the from and detach partly and to Strait Atlantic, Fram North towards way its forces on CBDW, This the ba- radiuses. extreme and features gradients area Mor- thymetric This the Rise. reaches Jesup water ris the East the turning towards After Greenland. towards the south follows ridge closely and Ridge Lomonosov tral Water Deep Basin Canadian constrained. the spatially of Basin Amerasian the from water deep the mapping, bathymetric and samples water measurements, oceanographic on Based events. these for time likely most the as in 6 results MIS events a erosional the of some of Dating Strait. towards Fram drifting the fragments shelf ice or icebergs American the of margins continental the along disproved. be could we LGM Instead Ocean the Arctic during pan shelf thick ice km 1 continuous a of Arctic the in events glacial Quaternary of dence Outlook fl wo BWoe h oooo Ridge Lomonosov the over CBDW of ow fi deiec o mle c shelves ice smaller for evidence nd fi fl fi dnspresented ndings w vrtecen- the over ows s he papers, three rst fi othe to c fl wof ow fl y well. sorsuysos xrml ihdmnscon- demands high extremely shows, study our As hswr ol o aebe osbewithout possible been have not would work This äkme ombord! välkommen hsopruiyadwr osatadreliable and constant a me were gave funded, and it opportunity got this project, this start to idea the people. many of support the Acknowledgements as aspects related methodology probably in will challenging compilation be further so DBM less This much and offshore. coast, in the exist to close accuracy areas and resolution spatial coast. cerning the to closer areas in focus needs the societal in as more different, are look on for may DBM lies Sea new Baltic focus A the the applications. often research and sea deep globe, oceans entire areas, the large or cover thesis this the in of discussed one was here presented fi ana- needs The the DBM. of Sea lysis Baltic new a of the compilation at aiming Administration, Maritime Swedish oia cecs hn o ma edr,Flo- Teodora, Emma, you Geo- Thank of Sciences. Department logical the at colleagues the and ment expeditions possible. these making Polar Swedish for the Secretariat as Research well as cruises, long and short the and papers the alltid jag att vec- och trevliga tillsammans kor många för samt besättningarna Lasse av och resten piruetter; och och Linda omvägar alla Ulf, för Kent, Ola Stickan, Ivan, To- Mats, Mattias; S., another och mas Erik yet Å., Tomas to Tack reluctant pirouette: never crews, standing I/B with expeditions Backman. Larry Jan especially and it, Mayer endorsed and project this hind mycket! så Tack worked. your actually my even attitude to end Much the mine. in than of surprise, solid some more in was belief ideas your my for that you and ideas Thank your sharing and science. inspirational to both approach your pragmatic from lot a me. learned supervising I balance in perfect guidance and a freedom with between years these over support s tp ntewy oto h te DBMs other the of Most way. the on steps rst is n oeot atnJkbsn o had You Jakobsson: Martin foremost, and First mgaeu o h peddwrigenviron- working splendid the for grateful am I of co-authors and lead- the to indebted am I on acquired was here used data the be- of stood Much who those of all to grateful am I Oden Oden — scienti ra hpwt out- with ship great a “ utwiei up it write just fi ate nall on parties c fi kknamig känna ck . Outlook 0.6 35 ”

Summary Summary: Mapping bathymetry rence, Daniela, Linda and Moo for the nice office http://www.ngdc.noaa.gov/mgg/global/global. company, and Björn for sharing quite some nerdy html. Accessed Apr. 30, 2011. spleens with me. Becker, J. J., D. T. Sandwell, W. H. F. Smith, Years before I started working on this thesis, J. Braud, B. Binder, J. Depner, D. Fabre, Christian Hübscher and Karsten Gohl showed me J. Factor, S. Ingalls, S.-H. Kim, R. Ladner, the fascination of the marine world. John Hall in- K. Marks, S. Nelson, A. Pharaoh, R. Trim- troduced me to ocean mapping—a field that may mer, J. von Rosenberg, G. Wallace, and P. ultimately be driven by the question of how to Weatherall (2009). Global Bathymetry and El- determine the bathymetry of a shopping mall. . . evation Data at 30 Arc Seconds Resolution: Thank you for the inspiration I took from the SRTM30_PLUS. Marine Geodesy, 32: 355–371. GEMME and CAMP cruises and our occasional DOI: 10.1080/01490410903297766. meetings afterwards. Bentley, C. R. (1987). Antarctic ice streams: A re- The Department of Geological Sciences and view. Journal of Geophysical Research, 92(B9): Stockholm University funded my work. Finan- 8843–8858. DOI: 10.1029/JB092iB09p08843. cial support for computing hardware from SSAG Björk, G., M. Jakobsson, B. Rudels, J. H. Swift, L. and conference support from ULI are gratefully ac- Anderson, D. A. Darby, J. Backman, B. Coakley, knowledged. Paper 3 is based on a project funded P. Winsor, L. Polyak, and M. Edwards (2007). by the Swedish Maritime Administration. The Bathymetry and deep-water exchange across the Knut and Alice Wallenberg Foundation, Veten- central Lomonosov Ridge at 88–89°N. Deep- skapsrådet and the Swedish Maritime Adminis- Sea Research I, 54(8): 1197–1208. tration financed the multibeam on I/B Oden with Boor, C. de (2001). A Practical Guide to Splines. grants to Martin Jakobsson. Ed. by J. E. Madsen and L. Sirovich. Vol. 27. Rebecca, ohne Deine Unterstützung über all die Applied Mathematical Sciences. New York: Jahre und ganz besonders Deinen Kraftakt in den Springer. ISBN 978-0387903569. letzten Monaten und Wochen wäre diese Arbeit Born, G. H., J. A. Dunne, and D. B. Lame nichts geworden. Eine größere Hilfe auf dem oft (1979). Seasat Mission Overview. Science, steinigen Weg hätte ich mir nicht wünschen kön- 204(4400): 1405–1406. DOI: 10.1126/sci- nen! Ich hoffe, die Zeit kommt in der ich Dir ein ence.204.4400.1405. bisschen davon zurückgeben kann — denn bis da- Briggs, I. C. (1974). Machine contouring using hin kann ich nur einfach Danke sagen. And thanks minimum curvature. Geophysics, 39: 39–48. for the idea with the cover figure! Telma, Dein Burrough, P. A. and R. A. McDonnel (1998). Prin- Lachen wenn ich nach Hause komme ist sowohl ciples of Geographical Information Systems. Ox- Motivation für den nächsten Tag als auch Erinne- ford, UK: Oxford University Press. ISBN 0-19- rung daran dass Manches so viel wichtiger ist als 823366-3. Arbeit. In Zukunft bin ich wieder mehr für Dich Calder, B. R. and L. A. Mayer (2003). Auto- da. matic processing of high-rate, high-density multibeam echosounder data. Geochemistry Geo- physics Geosystems, 4(6): 1048–1060. DOI: 0.7 References 10.1029/2002GC000486. Carbotte, S. M., R. Arko, D. N. Chayes, W. Haxby, Adler, R., L. Polyak, J. Ortiz, D. Kaufman, J. K. Lehnert, S. O’Hara, W. B. F. Ryan, R. A. Weis- Channell, C. Xuan, A. Grottoli, E. Sellén, and sel, T. Shipley, L. Gahagan, K. Johnson, and T. K. Crawford (2009). Sediment record from Shank (2004). New Integrated Data Manage- the western Arctic Ocean with an improved ment System for Ridge2000 and MARGINS Re- Late Quaternary age resolution: HOTRAX core search. EOS Transactions, 85(51): 553 & 559. HLY0503-8JPC, Mendeleev Ridge. Global and Cherkis, N. (2008). Worldwide seafloor swath- Planetary Change, 68(1-2): 18–29. mapping systems. Spreadsheet for download on Amante, C. and B. W. Eakins (2008). ETOPO1 GEBCO website. http://www.gebco.net/links/. 1 Arc-Minute Global Relief Model: Procedures, Accessed Apr. 10, 2011. Data Sources and Analysis. Boulder, Colorado: Darby, D., M. Jakobsson, and L. Polyak National Geophysical Data Center, NESDIS, (2005). Icebreaker expedition collects key Arctic NOAA and U. S. Department of Commerce.

36 odsel .A n .O efis(01.Arc- (2011). Jeffries O. M. and A. J. Dowdeswell, and McNutt, K. M. Naraghi, M. H., T. Dixon, Gowen, J. R. Mills, K. D. Barry, J. J., M. Devlin, vide. sphère la Sur (1934). B. Delaunay, oseg .adC shrig(91.The (1981). Tscherning C. and R. Forsberg, sec- Overconsolidated (1997). P. B. Flower, R. Crippen, R. Caro, E. Rosen, A. P. G., T. Farr, Krig- and Splines Comparing (1984). O. Dubrule, A. Muzi, D. Haagmans, R. R., M. Drinkwater, (2006). A. J. Dowdeswell, oorpyMission. Topography 93:429–439. 79(3): 7613(1997)025<0147:OSOTYP>2.3.CO;2. 10.1029/2005RG000183. DOI: 45(RG2004). .Fdn .Sve,adP et(08.Relation- (2008). Tett P. and Sivyer, D. Foden, J. s fHih aai rvt il Ap- Field Gravity in Collocation. Data by Height proximation of Use ka? 660 to Ocean: prior Arctic logy grounding Plateau, sheet Yermak ice the on tion Radar Shuttle The (2007). Alsdorf Bur- D. D. and Oskin, bank, Shi- M. Werner, J. M. Shaffer, Umland, S. J. E. Seal, mada, Paller, D. Roth, M. L. Kobrick, Rodriguez, M. Hensley, S. Duren, 338. ing. 92-9092-938-3. Workshop ISBN ESA. User SP-627. GOCE ESA International 3rd of Mission: M. ESA Gravity and GOCE The Kern, (2007). M. Fehringer Floberghagen, R. Popescu, 2011. 30, Apr. Accessed cruise_inventory/report/7692/. https://www. Institute. bodc.ac.uk/data/information_and_inventories/ Research Polar Activ- Scott Slide and ity Ice-Sheet Past Margin: bard York: New Springer. and Heidelberg, Berlin, M. A. L. land, introduction. An islands: In ice and shelves ice tic Research data. from altimeter prediction SEASAT Bathymetic (1983). Smith M. S. ma- UK in waters. depth rine Secchi and attenuation material, light particulate suspended between ships Sci. Classe. USSR, Nat. of Mat. Sciences of Academy the of 549–556. sea R ae lr oscus eotJR142. report cruise Ross Clark James RRS . rtciesevsadieislands ice and shelves ice Arctic fl ’ 52:147 25(2): , o n c data. ice and oor is oeErhEpoe.In Explorer. Earth Core First s optr Geosciences & Computers 8 1563–1571. 88: , I:793–800. VII: surn,CatladSefScience Shelf and Coastal Estuarine, – 5.DI 10.1130/0091- DOI: 150. O Transactions EOS eiw fGeophysics of Reviews ora fGeophysical of Journal ot n atSval- East and North ora fGeo- of Journal 023:327 10(2-3): , Proceedings d Cop- ed. , 86(52): , Bulletin Geo- – , , . eea ahmti hr fteOceans. the of Chart Bathymetric General (2006). Nychka D. and Genton, G. M. R., Furrer, M. Yamarone, J. C. Christensen, E. L.-L., Fu, interpolation: data Scattered (1982). R. Franke, the Modelling (1993). R. Forsberg, ae . .Gdn n .A ae (1995). Mayer A. L. and Godin, A. R., Hare, Ba- High-resolution Worldwide (2006). K. J. Hall, Meeting Ministerial Extraordinary HELCOM The (2008). Hughes J. T. and G. M. Grosswald, Marks M. K. and Smith, F. H. W. A., J. Goff, Armstrong A. and Mayer, A. L. V., J. Gardner, (2008). GEBCO p.3,2011. 30, Apr. dpe n1 oebr20 nKrakow, in 2007 November 15 on Adopted 2011. 30, Apr. eh e.Psdn,C,UA e Propulsion Jet USA: CA, Pasadena, rep. Tech. methods. some of Test eh e.Otw:Cnda yrgahcSer- Hydrographic Canadian Ottawa: rep. Tech. (2007). Mor- Hill Abyssal of Contributions The (2004). Submis- Potential Supports Mapping (2006). 10.1198/106186006X132178. 10.1007/BF00690568. DOI: 418. 10.1029/JB086iB09p07843. 10.1080/10889370802175929. vice. ac.uk/data/online_delivery/gebco/gebco_one_ Grid Bathymetric GEBCO Statistics Graphical and datasets. large spatial of interpolation for tapering Covariance Accessed http://hdl.handle.net/2014/34628. Technology. of Institute California Laboratory, Escud- (1994). P. ier and Dorrer, M. Menard, Y. Lefebvre, tation and requirements results. some data Methods, geoid: the of Research physical n we MliTasue)sudn systems sounding (Multi-Transducer) sweep and (Multi-beam) swath Canadian of estimation racy thymetry. 2011. 12, Mar. Accessed en_GB/ActionPlan/. http://www.helcom. Poland. Arctic pleistocene the in shelf Ocean. ice an for case Fabric. Gravity Oceanography Altimeter to Noise and phology 160. Sea. & the 157 of 87(16): Law N. U. to sion 20081212 2011. 30, Apr. Accessed minute_grid/. 8 181–200. 38: , oa Geography Polar ECMBli e cinPlan Action Sea Baltic HELCOM yr International Hydro tp/wwgbont.Accessed http://www.gebco.net/. . OE/oednMsinOverview Mission TOPEX/Poseidon uvy nGeophysics in Surveys 71:24–37. 17(1): , h EC_8gi,version grid, GEBCO_08 The 6B) 7843 86(B9): , ora fComputational of Journal ahmtc fCompu- of Mathematics 53:502 15(3): , 112:69 31(1-2): , https://www.bodc. . fi O Transactions EOS /BSAP/ActionPlan/ a 06 57. 2006: May , fi – . References 0.7 44:403 14(4): , ne-structure 84 DOI: 7854. – 2.DOI: 523. – 8 DOI: 98. Accu- 37 – , . . .

Summary Summary: Mapping bathymetry

Hartman, L. and O. Hössjer (2008). Fast (2007). The early Miocene onset of a ventilated kriging of large data sets with Gaussian circulation regime in the Arctic Ocean. Nature, Markov random fields. Computational Statis- 447: 986–990. DOI: 10.1038/nature05924. tics & Data Analysis, 52: 2331–2349. DOI: Jakobsson, M., R. Macnab, L. Mayer, R. Ander- 10.1016/j.csda.2007.09.018. son, M. Edwards, J. Hatzky, H. W. Schenke, Held, I. M. and B. J. Soden (2006). Robust Re- and P. Johnson (2008a). An improved bathy- sponses of the Hydrological Cycle to Global metric portrayal of the Arctic Ocean: Impli- Warming. Journal of Climate, 19(21): 5686– cations for ocean modeling and geological, 5699. geophysical and oceanographic anlyses. Geo- Hughes, T., G. H. Denton, and M. G. Grosswald physical Research Letters, 35: L07602. DOI: (1977). Was there a late-Würm Arctic Ice Sheet? 10.1029/2008GL033520. Nature, 266: 596–602. Jakobsson, M., C. Marcussen, and LOMROG ISO Technical Committee 211 (2003). Geographic Scientific Party (2008b). Lomonosov Ridge off information—Metadata. International Standard Greenland 2007 (LOMROG). Cruise Report. ISO/FDIS 19115:2003. http://www.iso.org/ Geological Survey of Denmark and Greenland. iso/catalogue_detail.htm?csnumber=26020. Ac- Jakobsson, M., J. Nilsson, M. A. O’Regan, J. Back- cessed Apr. 30, 2011. man, L. Löwemark, J. A. Dowdeswell, L. Mayer, Intergovernmental Oceanographic Commission, L. Polyak, F. Colleoni, L. Anderson, G. Björk, International Hydrographic Organization, and D. Darby, B. Eriksson, D. Hanslik, B. Hell, C. British Oceanographic Data Centre (2003). Cen- Marcussen, E. Sellén, and Å. Wallin (2010). An tenary Edition of the GEBCO Digital Atlas. Arctic Ocean ice shelf during MIS 6 constrained Published on CD-ROM on behalf of the Inter- by new geophysical and geological data. Quar- governmental Oceanographic Commission and ternary Science Reviews, 29: 3505–3517. DOI: the International Hydrographic Organization 10.1016/j.quascirev.2010.03.015. as part of the General Bathymetric Chart of the Jenkins, A., P. Dutrieux, S. S. Jacobs, S. D. McPhail, Oceans. Liverpool, U. K.: British Oceanographic J. R. Perrett, A. T. Webb, and D. White (2010). Data Centre. http://www.gebco.net/data_and_ Observations beneath Pine Island Glacier in products/gebco_digital_atlas/. Accessed Oct. 18, West Antarctica and implications for its re- 2010. treat. Nature Geoscience, 3(7): 468–472. DOI: International Hydrographic Organization (2008). 10.1038/ngeo890. IHO standards for hydrographic surveys. Spe- Jones, E. P., R. B., and L. G. Anderson (1995). cial Publication No 44. 5th edition. Imp. Moné- Deep waters of the Arctic Ocean: Origins and gasque, Monte Carlo: International Hydro- circulation. Deep-Sea Research I, 42: 737–760. graphic Organization. http : / / www . iho - ohi . DOI: 10.1016/0967-0637(95)00013-V. net/iho_pubs/standard/S-44_5E.pdf. Accessed Jung, W.-Y., P. R. Vogt, and I. F. Jewett Feb. 16, 2011. (2002). Bathymetric Error Evaluation for Sub- Jakobsson, M., L. Polyak, M. Edwards, J. Kleman, marine Cruises in the Arctic Ocean based on and B. Coakley (2008). Glacial geomorphology Track Crossover Differences. Tech. rep. RL/FR- of the central Arctic Ocean: the Chukchi Border- MM/7420–02-10,012. Washington, DC 20357- land and the Lomonosov Ridge. Earth Surface 5320: Naval Research Laboratory, 22pp, addi- Processes and Landforms, 33(4): 526–545. tional material in CDROM. Jakobsson, M., N. Cherkis, J. Woodward, R. Mac- Katzil, Y. and Y. Doytsher (2000). Height es- nab, and B. Coakley (2000). New Grid of Arc- timation methods for filling gaps in grid- tic Bathymetry Aids Scientists and Mapmakers. ded DTM. Journal of surveying engineering, EOS Transactions, 81(9): 89, 93 & 96. 126: 145–163. DOI: doi:10.1061/(ASCE)0733- Jakobsson, M., B. Calder, and L. Mayer (2002). 9453(2000)126:4(145). On the effect of random errors in gridded ba- Kimball, R. and M. Ross (2002). The data ware- thymetric compilations. Journal of Geophysical house toolkit: the complete guide to dimensional Research, 107(B10): 2358–2368. modeling. 2nd ed. New York: Wiley Computer Jakobsson, M., J. Backman, B. Rudels, J. Nycander, Publishing. ISBN 0-471-20024-7. M. Frank, L. Mayer, W. Jokat, F. Sangiorgi, M. Klenke, M. and H. W. Schenke (2002). A new ba- O’Reagan, H. Brinkhuis, J. King, and K. Moran thymetric model for the central Fram Strait. Ma-

38 abn . .Mro,L-.F,J .Willis, K. J. Fu, L.-L. Morrow, R. J., Lambin, Ed- M. Jokat, W. Coakley, B. Y., Kristoffersen, Ha- I. Fiedler, H. Moreira, A. G., Krieger, alwk,W,D abe .Wlzwk,U. Walczowski, W. Marble, D. W., Maslowski, Sandwell T. D. and Smith, F. H. W. M., K. Marks, An (2009). Smith F. H. W. and M. K. Marks, Something (2000). Jakobsson M. and R. Macnab, (2002). X. Lurton, of Comparison (1999). Götze H.-J. and X. Li, Ocean Arctic (1994). McAdoo D. and S. Laxon, ad,H rke n .Gegdl(2004). Gjengedal J. and Brekke, H. wards, Altimetry. the in icebergs draft deep of tale a Ocean: Arctic 21) vlto fErr ntealtimetric the in Errors of Evolution (2010). and Lindstrom, E. Coutin-Faye, S. Thouvenot, Formation Satellite A TanDEM-X: (2007). 9 A06 O:10.1029/2003PA000985. DOI: PA3006. 19: 10.1109/TGRS.2007.900693. 10.1007/s11001-008-9060-y. 898–900. 18(8): 10.1126/science.265.5172.621. 10.1080/01490419.2010.491030. nciaooia as et n attransports salt and heat, (2004). mass, Semtner climatological J. On A. and Clement, L. J. Schauer, 10.1007/s11001-010-9102-0. DOI: 223–238. and Earth Google GEBCO. by used model bathymetry data. sounder Researches Geophysical echo multibeam beam single and ocean deep for model uncertainty 2–16. Case a as Study. Ocean Arctic the with Maps, Ba- thymetric Regional Construct to Data and Contemporary Historic Compiling New: Something Old, 3-540-42967-0. ISBN applications and principles acoustics: methods. gridding some Satellite ERS-1 From Derived Field Gravity Mis- sion. OSTM/Jason-2 The E. (2010). Mignogno Parisot, M. F. Bannoura, W. Za- Vaze, G. P. Perbos, ouche, J. Lillibridge, J. Bonekamp, H. in ter in the and Basin Eurasia central Ridge, Lomonosov the on erosion Seabed Re- and Sensing Interferometry. Geoscience mote on SAR Transactions IEEE High-Resolution Zink M. for and Younis, M. Werner, M. jnsek, 10.1023/A:1025764206736. DOI: Researches Geophysical rine fl aieGeodesy Marine wo cbr motion? iceberg on ow nentoa yrgahcReview Hydrographic International aieGohsclResearches Geophysical Marine Science 51) 3317 45(11): , nitouto ounderwater to introduction An 6(12:621 265(5172): , 94:239 29(4): , 3S) 4 33(S1): , fl ec fAlni wa- Atlantic of uence h edn Edge Leading The Paleoceanography 34:367 23(4): , – 31 DOI: 3341. – – – 2.DOI: 624. 5.DOI: 250. 5 DOI: 25. Springer. . Marine 31(3): , 1(1): , – 378. , , ile,K,M tenom .Ø le,D.-I. Olsen, Ø. B. Stjernholm, M. K., Nielsen, (2001). G. Naryshkin, (1998). Group Working Hoc Ad Metadata Arc- the in sheet ice former A (1970). H. J. Mercer, Sea in Frontiers (2006). L. Mayer, geostatistics. of Principles (1963). G. Matheron, tee,D n .A odsel(09.An (2009). Dowdeswell A. J. and D. Ottesen, O Jakobsson, M. Dowdeswell, A. J. R., Noormets, and Larter, D. R. Jacobs, S. S. O., F. Nitsche, ’ cdm fSciences. of Academy emkPaeu In Plateau. Yermak eh e.FD-T-0-98 eea Ge- Federal FGDC-STD-001-1998. rep. Tech. eh e.Dnak ijudrøesr http: Miljøundersøgelser. Danmarks rep. Tech. (2000). 1: 10.1016/j.quascirev.2010.09.009. 10.1029/2007GC001694. //www.dmu.dk/udgivelser/kort-og-geodata/ais/ ora fGohsclResearch Geophysical of Journal i Ocean tic 2011. 30, Apr. Accessed csdgm. gov/metadata/geospatial-metadata-standards# http://www.fgdc. Committee. Data ographic Metadata Geospatial Digital for Standard tent Palaeoecology and Ocean. tic 005-0267-x. searches Visualization. and ping Geology Economic 10.1029/2001JC001039. DOI: simulation. a model from ice-ocean Strait coupled Fram pan-Arctic and Sea Barents the through ne-c-temgaitdmri:Submarine margin: glaciated inter-ice-stream Plateau. Reviews Yermak Science and Lomono- Ridge the sov on sediments of implications overconsolidated geological Glacial (2010). ner C43C-0564. ice O C. and Geosystems Geophysics istry glaciology. Amund- geo- and oceanography, for logy, the Implications shelf: of continental Sea Bathymetry sen (2007). Gohl K. Dan- (in 2011 ish). 13, Apr. Accessed ais-rapport/. Larsen H. and Bacher, V. Jensen, E. M. J. Johannsen, Hvidberg, Her- K. B. V. Rolev, Skov-Petersen, M. H. A. mansen, Hansen, S. H. Groom, G. Kjeldgaard, A. Madsen, I.-L. Müller-Wohlfeil, ea,M,M aoso,adN Kirch- N. and Jakobsson, M. M., Regan, 2500000 fl wadieegatvt ntesouthern the on activity iceberg and ow 71:7 27(1): , ra nomtosSystemet Informations Areal ’ oag 21) e vdneo past on evidence New (2010). Cofaigh ahmti otu a,scale map, contour Bathymetric . Palaeogeography, Palaeoclimatology t eesug usa Russian Russia: Petersburg, St. . 92-6:3532 29(25-26): , – :19–27. 8: , 8 1246–1266. 58: , G alMeeting Fall AGU 7 O:10.1007/s11001- DOI: 17. otmrle fteArc- the of relief Bottom aieGohsclRe- Geophysical Marine :Q00.DOI: Q10009. 8: , 0:C03032. 109: , . References 0.7 – Quaternary 54 DOI: 3544. fl Geochem- o Map- oor Abstract . — Con- AIS 39 . .

Summary Summary: Mapping bathymetry

landforms and a geomorphic model based on Siemens, C. W. (1876). On determining the depth marine-geophysical data from Svalbard. Bulletin of the sea without the use of a sounding line. of the Geological Society of America, 121(11- Philos. Trans. R. Soc. London, 166: 671–692. 12): 1647–1665. DOI: 10.1130/B26467.1. Smith, D. E., M. T. Zuber, S. C. Solomon, R. Pajarola, R., M. Antonijuan, and R. Lario (2002). J. Phillips, J. W. Head, J. B. Garvin, W. B. QuadTIN: Quadtree based Triangulated Irreg- Banerdt, D. O. Muhleman, G. H. Pettengill, G. ular Networks. In Proceedings IEEE Visualiza- A. Neumann, F. G. Lemoine, J. B. Abshire, O. tion. IEEE Computer Society Press, 395–402. Aharonson, C. D. Brown, S. A. Hauck, A. B. Parkinson, B. W., T. Stansell, R. Beard, and K. Gro- Ivanov, P. J. McGovern, H. J. Zwally, and T. mov (1995). A history of satellite navigation. C. Duxbury (1999). The Global Topography of Navigation, 42(1): 109–164. Mars and Implications for Surface Evolution. Pe’eri, S., J. V. Gardner, L. G. Ward, and J. R. Science, 284: 1495–1503. DOI: 10.1126/sci- Morrison (2011). The Seafloor: A Key Factor in ence.284.5419.1495. Lidar Bottom Detection. IEEE Transactions on Smith, W. H. F. (1993). On the Accuracy of Dig- Geoscience and Remote Sensing, 49(3): 1150– ital Bathymetric Data. Journal of Geophysical 1157. DOI: 10.1109/TGRS.2010.2070875. Research, 98(B6): 9591–9603. Perry, R., H. Fleming, J. Weber, Y. Kristoffersen, J. Smith, W. H. F. and D. T. Sandwell (1994). Bathy- Hall, A. Grantz, G. Johnson, N. Cherkis, and B. metric prediction from dense satellite altimetry Larsen (1986). Bathymetry of the Arctic Ocean. and sparse shipboard bathymetry. Journal of Map and Chart Series, Scale 1:4704075. Boul- Geophysical Research, 99(B11): 21803–21824. der, Colorado: Geological Society of America. – (1997). Global Sea Floor Topography from Satel- Polyak, L., D. A. Darby, J. F. Bischof, and M. Ja- lite Altimetry and Ship Depth Soundings. Sci- kobsson (2007). Stratigraphic constraints on late ence, 277: 1956–1962. Pleistocene glacial erosion and deglaciation of Smith, W. H. F. and P. Wessel (1990). Gridding the Chukchi margin, Arctic Ocean. Quaternary with continuous curvature splines in tension. Research, 67(2): 234–245. Geophysics, 55(3): 293–305. Reuter, H., A. Nelson, and A. Jarvis (2007). An Spielhagen, R. F., K. H. Baumann, H. Erlenkeuser, evaluation of void filling interpolation methods N. R. Nowaczyk, N. Nørgaard-Pedersen, C. for SRTM data. International Journal of Geo- Vogt, and D. Weiel (2004). Arctic Ocean deep- graphic Information Science, 21(9): 983–1008. sea record of northern Eurasian ice sheet history. Sandwell, D. T. and W. H. F. Smith (1997). Marine Quaternary Science Reviews, 23(11-13): 1455– gravity anomaly from Geosat and ERS 1 satellite 1483. altimetry. Journal of Geophysical Research, 102: Stocks, T. (1937). „Morphologie des Atlanti- 10039–10054. schen Ozeans“. In Wissenschaftliche Ergebnis- Schauer, U., B. Rudels, P. Jones, L. Anderson, R. se der Deutschen Atlantischen Expedition auf Muench, G. Björk, J. Swift, V. Ivanov, and A.-M. dem Forschungs- und Vermessungsschiff Meteor Larsson (2002). Confluence and redistribution 1925–1927. Vol. III — erster Teil. Verlag von of Atlantic waters in the Eurasian Basin: results Walter de Gruyter & Co. from ACSYS-96. Annales Geophysicae, 20(2): Task group on gridding of the GEBCO SCDB 257–273. (1997). On the preparation of a gridded data set Schutz, B. E., H. J. Zwally, C. A. Shuman, from the GEBCO Digital Atlas contours. Tech. D. Hancock, and J. P. DiMarzio (2005). rep. Version 9 - 16th June 1997. GEBCO. Overview of the ICESat mission. Geophysi- Thiede, J., A. M. Myhre, J. V. Firth, G. L. Johnson, cal Research Letters, 32(21): L21S01. DOI: and W. F. Ruddiman, eds. (1996). Proceedings 10.1029/2005GL024009. of the Ocean Drilling Program. Scientific results. Seifert, T., F. Tauber, and B. Kayser (2001). A 151. Ocean Drilling Program. College Station, high resolution spherical grid topography of the TX. DOI: 10.2973/odp.proc.sr.151.1996. Baltic Sea — 2nd edition. In Baltic Sea Science Torge, W. (2001). Geodesy. 3rd ed. Berlin and Congress. Poster 147. Stockholm. http://www. New York: de Gruyter. ISBN 3-11-017072-8. io-warnemuende.de/iowtopo. Accessed Feb. 16, Tsoukalas, N., C. Roedle, and G. Schwab (1999). 2011. “Bathymetric measurements”. In ARCTIC ’98: The Expedition ARK-XIVII a of RV “Po-

40 ot .R,K rn,adE udo (1994). Sundvor E. and Crane, K. R., P. Vogt, (1982). Nations United Oceanic National Commerce, of Department S. U. ot .R,M .Cro,W-.Jn,and Jung, W.-Y. Carron, J. M. R., P. Vogt, (2000). Nagel J. D. and Jung, W.-Y. R., P. Vogt, emkPaeu iecnad35kzevi- kHz 3.5 and sidescan Plateau: Yermak BO0Fle/OTPF cesdAr 30, Apr. Accessed ABLOS01Folder/VOGT.PDF. Mnc) http://www.gmat.unsw.edu.au/ablos/ (Monaco). 7613(1994)022<0403:DPIPOT>2.3.CO;2. 2011. In portray- bathymetry. in global re-use ing for Opti- surveys UNCLOS: 76 Article and Map- mizing (GOMaP) Ocean Project Global The ping (2001). Macnab R. 258. & 254 the Millennium. Start to New Resolution Matchless A GOMaP: Ocean. Arctic the in pos- a sheet and Geology ice fronts marine ice calving sible thick for dence the on ploughmarks iceberg Pleistocene Deep 1, Mar. 2011. Accessed overview_convention.htm. Sea the Depts/los/convention_agreements/convention_ of Law the on tion 16,2011. Feb. Accessed fliers/06mgg01.html. http://www.ngdc.noaa.gov/mgg/ Colorado. (ETOPO2v2) Data Relief Global ded (2006). Center Data Geophysical National and Administration, Atmospheric and 76 Meeresforschung, und Polar- für Institut Alfred-Wegener- Meeresforschung. und Polar- larstern ” 25:403 22(5): , n1998 in d yW oa.Brct zur Berichte Jokat. W. by Ed. . O Transactions EOS – 0.DI 10.1130/0091- DOI: 406. ntdNtosConven- Nations United BO Conference ABLOS http://www.un.org/ . -iueGrid- 2-minute Boulder, . 81(23): , – 81. . ag .S,S-.Ko .B e,adP-.Hung P.-S. and Lee, F.-B. Kao, S.-P. C.-S., Yang, Nohr C. and Björk, G. Yuan, X. K., A. Wåhlin, Arvidson T. and Goward, S. L., D. Williams, Atlantis? this Is (2009). Phillips R. and V. Wheeler, im- New, (1998). Smith F. H. W. and P. Wessel, detector cross-error A XOVER: (1989). P. Wessel, ue,M,D mt,S ooo,J bhr,R. Abshire, J. Solomon, S. Smith, D. M., Zuber, o.XX-2 nentoa oit o Pho- for Society International XXXV-B2. Vol. 2011. 31, Mar. Accessed fa,O hrno,K ihag,P od H. Ford, P. Fishbaugh, K. Aharonson, O. Afzal, 20) wledfeetitroainmeth- interpolation different Twelve (2004). In (2010). tomor- and today, yesterday, Landsat: (2006). Sun The uky 778ff. Turkey, 10.1175/2010JPO4431.1. d:acs td fSre ..In 2 Commission 8.0. of Surfer Proceedings of Congress, study PRS case a ods: Oceanography ical Shelf. Amundsen central the in sensing row. co.uk/sol/homepage/news/article2255989.ece. re- Tools Mapping leased. Generic of version proved 333–346. data. track for 00 O:10.1126/science.282.5396.2053. DOI: 2060. Or- Mars Altimeter. the Laser from biter Mars of region the polar of north Observations (1998). al. et Garvin, J. Frey, Istanbul, Sensing. Remote and togrammetry htgamti niern n remote and engineering Photogrammetric 21) 1171–1178. 72(10): , O Transactions EOS e.2,20:1 http://www.thesun. 1. 2009: 20, Feb. , fl wo amcruplrde water deep circumpolar warm of ow optr Geosciences & Computers 06:1427 40(6): , Science 94) 579. 79(47): , 8(36:2053 282(5396): , ora fPhys- of Journal – . References 0.7 44 DOI: 1434. XhIS- XXth 15(3): , 41 – .

Summary 42 Meddelanden från Stockholms universitets institution för geologiska vetenskaper Nº 344

Nº 334: Blaj, T. Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial Pacific Ocean: Taxonomy, preservation history, biochronology and evolution. PhD thesis. Stockholm: 2009. Nº 335: Colleoni, F. On the Late Saalian glaciation (160–140ka): A climate modeling study. PhD thesis. Stockholm: 2009. Nº 336: Konn, C. Origin or organic compounds in fluids from ultramafic-hosted hydrothermal vents of the Mid-Atlantic Ridge. PhD thesis. Stockholm: 2009. Nº 337: Sellén, E. Quaternary paleoceanography of the Arctic Ocean: A study of sediment stratigraphy and physical properties. PhD thesis. Stockholm: 2009. Nº 338: Sundvall, R. Water as a trace component in mantle pyroxene: Quantifying diffusion, storage capacity and variation with geological environment. PhD thesis. Stockholm: 2010. Nº 339: Pettersson, C.-H. The tectonic evolution of northwest Svalbard. PhD thesis. Stockholm: 2010. Nº 340: Svahnberg, H. Deformation behaviour and chemical signatures of anorthosites: Examples from southern West Greenland and south-central Sweden. PhD thesis. Stockholm: 2010. Nº 341: Anderson, J., M. Jakobsson, and OSO 0910 scientific party. Oden Southern Ocean 0910. Cruise report. Stockholm: 2010. Nº 342: Borthwick, V. Fundamentals of substructure dynamics: In-situ experiments and numerical simulation. PhD thesis. Stockholm: 2010. Nº 343: Siljeström, S. Single fluid inclusion analysis using ToF-SIMS: Implications for ancient Earth biodiversity and paleoenvironment studies. PhD thesis. Stockholm: 2010.

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