Signifikanz Bathymetrischer Daten

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Significance of Bathymetric Data in Polar and
Marine Research and Beyond
Norbert Ott Hans Werner Schenke Alfred Wegener
Institute for Polar and Marine Research Bathymetry
und Geodesy Bremerhaven, Germany
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Alfred Wegener Institute

• Founded in 1980
• Member of Helmholtz-Gemeinschaft Deutscher
  Forschungszentren (HGF)
• 800 Employees in Bremerhaven, Potsdam,
  Helgoland, and Sylt
• Budget in 2006 100 Mio. Euro
• Financing 90 BMBF, 10 Fed. States
• Scientific program with three faculties Geo, Bio
  und Climate
• Logistics 3 ships, 2 airplanes
• 6 stations Neumayer, Koldewey etc.

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Bathymetry in Polar Research
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Bathymetry in Marine Research
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Why Sea Floor Topography Matters?

• Defines gates and barriers
• e.g. Drake Passage, Tasman Gateway
• Steers global currents
• e.g. Antarctic Circumpolar Current

• Thermohaline circulation
• e.g. bottom water formation
• Influences global climate
• e.g. Antarctic glaciation

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Applications

• Geosciences
• Endogenous processes
• Exogenous processes
• Disaster management
• Oceanography
• Circulation and Flux
• Numeric Modeling
• Biology
• Ecology und Biodiversity
• Protection and conservation
• Observing systems
• Physical boundary
• Domains and Variables

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Scientific Projects

• Arctic Ocean
• Fram-Strait (1997)
• Gakkel-Ridge (2001)
• IBCAO (current)

• Southern Ocean
• BCWS (1998-2001)
• INT 9057, 9055 (current)
• IBCSO (current)

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Gakkel-Ridge in the Arctic Ocean

• AMORE Expedition 2001
• Mid-ocean Ridge
• 1800 km length, 3000 m height
• Characteristics
• Ultraslow spreading
• Graben structure
• thin crustal thickness
• Amagmatic/aseismic (?)
• Defined as new Type of MOR
• cold and rigid crust

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IBC of the Weddell Sea
Bathymetric Data GEBCO GDA IHO DCDB and
HOs MB-Daten
Topographic Data ADD 1.94, 1994
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Gravity vs. Bathymetry

• Gravity
• Herring bone pattern
• Heterogenic gravity field
• Density contrasts
• Bathymetry
• No Herring bone pattern
• Homogenic Topography
• Seismic findings
• Sediments (1000 m)
• Smooth topography

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A Bath Tube After All?
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The Weddell Sea Polynya

• Polynya hole in sea ice
• First in 1975, then in 1994
• Topography
• Maud Rise (3000 m)
• Volcanic complex
• Steering
• Local vortex near the rise
• Up-streaming currents
• Energy transport - heat

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Atmospheric Analogon
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Project Coolchart
Bathymetric Data MB-Data, 1989-2007 BCWS, 1998
Topographic Data Radarsat Mosaic, 1997 coast
line, contours
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IBC of the Southern Ocean
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The GIS Database

• Bathymetric data of the SO
• Raw data, Grids, contours and Charts
• Topographic data of Antarctica
• DEM, ice thickness, Subglacial topo.
• Coastline, grounding line, ice edge

• Additional data
• Satellite imagery
• Feature names
• Limits of seas
• Metadata

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DEM in Tsunami Warning Systems
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Bathymetry goes WWW
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ENC Prototyp of New York City
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State-of-the-Art Mars vs. Earth

• HRSC 10 m resolution
• Global coverage of Mars
• Multi-spectral imagery
• Stereoscopic views

• Multibeam 100 m
• Only local coverage
• Color-coded DEM
• Perspective views

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Conclusions

• Depth values provide digital data for numerical
  modeling by use of digital tool with large data
  gaps in the polar areas.
• Digital data processing enables the performance
  of GIS based analyses as well as the generation
  of thematic maps for improved visualization of
  the sea floor and its dynamic processes.
• Bathymetric data of AWI are used for applications
  in the fields of Geo-, Bio- und Climate Sciences
  and for disaster management and safe navigation.
• Integration of bathymetric data with additional
  geo-scientific data enables the observation und
  evaluation of polar ecosystems and their
  conservation.