The IBCSO Poster, 2013, is a polar stereographic view of the Southern Ocean displaying bathymetric contours south of 60° S at a scale of 1:7,000,000. The poster size is 39.25 x 47.125 inches.
To cite this chart or the IBCSO grid please use:
Arndt, J.E., H. W. Schenke, M. Jakobsson, F. Nitsche, G. Buys, B. Goleby, M. Rebesco, F. Bohoyo, J.K. Hong, J. Black, R. Greku, G. Udintsev, F. Barrios, W. Reynoso-Peralta, T. Morishita, R. Wigley, "The International Bathymetric Chart of the Southern Ocean (IBCSO) Version 1.0 - A new bathymetric compilation covering circum-Antarctic waters", Geophysical Research Letters, doi: 10.1002/grl.50413
The International Bathymetric Chart of the Southern Ocean (IBCSO) program is endorsed by the Intergovernmental Oceanographic Commission (IOC) of UNESCO, the International Hydrographic Organization (IHO), and the Scientific Committee on Antarctic Research (SCAR). Since 2004, IBCSO has been an Expert Group within the SCAR Standing Scientific Group on GeoSciences (SSG-GS). In 2006, IBCSO was established as a regional ocean mapping project under the IHO/IOC General Bathymetric Chart of the Oceans (GEBCO) program. The project aim is to generate the first seamless bathymetric grid of the Southern Ocean covering the entire Antarctic Treaty Area south of 60 degrees S by compiling all available data from various international sources. The IBCSO v1.0 grid has a resolution of 500 m x 500 m and is based on a polar stereographic projection at 65 degrees S on the WGS-84 ellipsoid. The grid is available as open source for download. This printed chart represents one product resulting from the IBCSO project.
Bathymetric grid generation:
The IBCSO data base consists of more than 4200 million ocean soundings from various sources worldwide. The data sets are of diverse type and quality. About 98% of the data points are from multibeam surveys. The remaining 2% are from singlebeam surveys, digitized Nautical Charts, or data sets containing various types of data. Approximately 17 % of the bathymetric grid cells are directly constrained by real soundings.
The subglacial bed elevation layer of Bedmap2 was used for the topography of continental Antarctica and for the sub ice-shelf bathymetry. Sonar sounding data were validated, homogenized and stored into a generic data format to generate the IBCSO digital bathymetric model. The data was subsequently cleaned and gridded in an iterative process until a satisfactory result was achieved. The gridding utilized the remove-restore method in conjunction with the newly developed gap-fill method. The gap-fill method is restocking major spatial data gaps with aligned predicted bathymetry. The applied remove-restore method was a two-step gridding algorithm. Firstly, the entire dataset was gridded at low resolution, here 2000 m, using the bi-cubic splines under tension algorithm. The grid was then filtered and resampled at high resolution, here 500 m. Secondly, all high quality data with sufficient areal density, i.e. from multibeam surveys, was gridded at high resolution using the nearest neighbor gridding algorithm. Finally, in locations where high quality data was available, grid cells from the lower resolution grid were removed and restored by the high quality data grid cells. The gap-fill method compared the GEBCO_08 grid, created using predicted bathymetry, to sonar soundings of the IBCSO data base. A blockmedian filter, with 10 km cellsize, was applied to the depth differences of the compared points. Based on these points, a difference grid was created to adjust the GEBCO_08 grid. In a final step, the adjusted bathymetric model replaced the interpolated areas outside a 10 km transition zone next to grid cells, directly constrained by soundings. In the transition zone both grids were bent into each other using the hyperbolic weighting function 1/d, with d being the distance to the next directly constrained cell. For a more detailed description of the grid generation please see the IBCSO release paper (Arndt et al 2013; doi:10.1002/grl.50413).
Bathymetric and topographic elevations are from the IBCSO v1.0 grid. Ice surface elevations are from the Bedmap2 data set. Coastlines, grounding lines, rock outcrops, and the names and positions of permanent stations in Antarctica are taken from the SCAR Antarctic Digital Database v6.0. Names of undersea features are taken from the GEBCO Sub-Committee on Undersea Feature Names (SCUFN) Gazetteer, Edition 2011. Names of ocean bodies are taken from the 4th edition of IHO Publication S-23, "Limits of Oceans and Seas". Names on continental Antarctica are taken from the SCAR Composite Gazetteer (CGA). The selection of the names has been agreed on by the members of the Editorial Board.
Grid and Chart retrieval:
The IBCSO v1.0 grid can be obtained from the project website (www.ibcso.org) or via doi:10.1594/PANGAEA.805736 in different data formats and projections. A digital copy of this chart in PDF format can be retrieved from the same source.
For additional information and data from IBCSO, please visit the IBCSO web pages:
Antarctic Map: Bathymetry and Geological Setting of the Drake Passage:
In December 2016, a new Antarctic map, “Bathymetry and Geological Setting of the Drake Passage”, was released. This SCAR product represented an international collaborative effort coordinated by the Spanish Geological Survey (IGME) and the British Antarctic Survey (BAS), working together with the Korea Polar Research Institute (KOPRI), the Alfred Wegener Institute (AWI) and the United States Antarctic Program (USAP).
The map covers an area of 1470000 km2 between parallels 52ºS and 63ºS and between meridians 70ºW and 50ºW, where the high resolution bathymetric data covers more than 70% of the region with a 200 m cell resolution of the sea floor topography. The data were collected over the last 25 years on more than one hundred oceanographic cruises onboard six different Antarctic research vessels. This initiative is part of SCAR's IBCSO (International Bathymetric Chart of the Southern Ocean) Expert Group, which recognises the importance of regional data compilations in Antarctic areas of particular scientific interest. The map has been published by the BAS and the IGME, with support from SCAR through the Geosciences Group.
The Drake Passage is an oceanic gateway of approximately 850 km width located between South America and the Antarctic Peninsula that connects the southeastern Pacific and the southwestern Atlantic oceans and influences mantle flow, oceanographic water mass exchanges and migrations of biota. This gateway opened within the framework of the geological evolution of the Scotia Arc; a tectonic setting which developed since the early Oligocene and includes the Scotia and Sandwich plates. It is bounded to the north by the North Scotia Ridge, to the south by the South Scotia Ridge, to the west by the Shackleton Fracture Zone, and to the east by the South Sandwich Trench. The Scotia Sea contains several active and extinct spreading ridges that led to the opening of the Drake Passage. Several continental banks and oceanic basins are located in Scotia Sea, most notably in its southern part.
The geodynamic evolution of the region, seismic activity and tectonic data suggest a complex evolution of the Drake Passage such that the Shackleton Fracture Zone began as an oceanic ridge-to-ridge transform fault with strike-slip motion along most of its length, and subsequently became a transpressive transcurrent fault zone as it is at present. The Shackleton Fracture Zone, which occupies a central position in the Drake Passage, intersects two extinct spreading centres – the West Scotia Ridge (extinct 6.4 Ma ago) and the Phoenix-Antarctic Ridge (extinct 3 Ma ago), and is an intra-oceanic ridge which rises several hundreds to thousands of metres above the surrounding seafloor. Uplift of the Shackleton Fracture Zone in the last 8 Myr has formed a barrier for oceanic bottom currents.
The opening of the main southern oceanic gateways, Drake Passage and the Tasmanian gateway, separating South America and Australia from Antarctica respectively, permitted the present pattern of global ocean circulation to be established. This allowed extensive exchange of water between the main ocean basins and led to the development of the Antarctic Circumpolar Current, which contributed to the thermal isolation of Antarctica, was partially responsible for global cooling at the Eocene-Oligocene boundary and played an important role in middle Miocene cooling.
Reference of the map:
Bohoyo, F., Larter, R.D., Galindo-Zaldívar, J., Leat, P.T., Maldonado, A., Tate, A.J., Gowland, E.J.M., Arndt, J.E., Dorschel, B., Kim, Y.D., Hong, J.K., Flexas, M., López-Martínez, J., Maestro, A., Bermudez, O., Nitsche, F.O., Livermore, R.A., Riley, T.R. 2016. Bathymetry and Geological Setting of the Drake Passage (1:1 500 000). BAS GEOMAP 2 Series, Sheet 7, British Antarctic Survey, Cambridge, UK.
Poster presentation at XXII ISAES
, 16. July 2015. Open Poster.
Oral presentation at the Eighth Annual GEBCO Bathymetric Science Day
in Venice, 8. October 2013.
- IBCSO V1.0 Release Paper: "The International Bathymetric Chart of the Southern Ocean (IBCSO) Version 1.0 - A new bathymetric compilation covering circum-Antarctic waters", Geophysical Research Letters, doi: 10.1002/grl.50413, Arndt et al. 2013
Oral presentation at the "25. Internationale Polartagung der DGP" in Hamburg
, 20. March 2013.
Poster presentation at the AGU Fall Meeting
in San Francisco, 7. December 2012.
Oral presentation at the XXXII SCAR and Open Science Conference in Portland
, 16. July 2012 entitled 'IBCSO v1 - A preview of the International Bathymetric Chart of the Southern Ocean'.
Poster presentation at the AGU Fall Meeting
in San Francisco, 5. December 2011.
- Oral presentation at the Intergeo 2008 HTML logo.png, Bremen, Germany, October 2008.
- Oral presentation by Ott and Schenke entitled 'Polar Ocean Mapping: Significance of Bathymetry for Observing Systems' at the SCAR/IASC Open Science Conference, St Petersburg, Russia, 8-11 July 2008.
- Poster presentation at the SCAR/IASC Open Science Conference, St Petersburg, Russia, 8-11 July 2008.
- Joint IBCAO and IBCSO poster presentation at the SCAR/IASC Open Science Conference, St Petersburg, Russia, 8-11 July 2008.
- Hydro International Feature Article entitled 'Southern Ocean Bathymetry', November 2007
- Oral presentation by Ott and Schenke entitled 'GIS based Data Compilation of the new IBCSO' at the 10th ISAES HTML logo.png , University of California, Santa Barbara, USA, August 2007
- Extended Abstract of a poster presentation by Macnab et al., at the International Symposium Asian Collaboration in IPY 2007-2008, Tokyo, Japan, 1 March 2007.