GIS Tools for Accessing Arctic Bathymetry:GIS Tools for Accessing Arctic Bathymetry: International Bathymetric Chart of the Arctic OceanInternational Bathymetric Chart of the Arctic Ocean (I (IBCAOBCAO))

MartinMartin JakobssonJakobsson

Center for Coastal and Ocean MappingCenter for Coastal and Ocean Mapping

Joint Hydrographic CenterJoint Hydrographic Center

University of New HampshireUniversity of New Hampshire

1.1. TThe IBCAO bathymetry modelhe IBCAO bathymetry model

2.2. Users of IBCAOUsers of IBCAO

3.3. GIS tools for accessing the IBCAO GIS tools for accessing the IBCAO grid modelgrid model

4.4. Future IBCAO GIS products Future IBCAO GIS products (Error (Error estimation of the IBCAO bathymetry, vector estimation of the IBCAO bathymetry, vector contours)contours)

IBCAOIBCAOGrid model representing Grid model representing

Arctic Ocean bathymetry Arctic Ocean bathymetry

and topographyand topography

Grid cell spacing: Grid cell spacing:

2.5 x 2.5 km2.5 x 2.5 km

Projection: Projection:

Polar stereographicPolar stereographic

True scale: True scale: 7575ºº NN

Datum: Datum: WGS 84WGS 84

TRACKLINE SOURCESTRACKLINE SOURCES

MAP SOURCESMAP SOURCES

SOURCESSOURCES

GRID COMPILATIONGRID COMPILATION

Data Data cleaning & cleaning &

miningmining(MGE)(MGE)

Block median filteringBlock median filtering

Gridding using continuous curvature splines in Gridding using continuous curvature splines in tension (Smith & Wessel, 1990)tension (Smith & Wessel, 1990)

Data gatheringData gathering(MGE)(MGE)

IBCAO web site:IBCAO web site:http://www.ngdc.noaa.gov/mgg/bathymetry/arctic/arctic.htmlhttp://www.ngdc.noaa.gov/mgg/bathymetry/arctic/arctic.html

USERS OF THE IBCAO BATHYMETRY GRIDUSERS OF THE IBCAO BATHYMETRY GRID

IBCAO web site statistics 2000IBCAO web site statistics 2000

Oceanography modelingOceanography modeling (e.g. Arctic ice-ocean model for the Polar Ice prediction System (e.g. Arctic ice-ocean model for the Polar Ice prediction System

(PIPS), US Naval Postgraduate School; ARCICE, Southampton Oceanography Centre, UK)(PIPS), US Naval Postgraduate School; ARCICE, Southampton Oceanography Centre, UK)

Geophysical modelingGeophysical modeling

Ice sheet modelingIce sheet modeling

Cartographic applications Cartographic applications

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IBCAO web site news:

February, 26 652 accesses and 99297 hits

GIS Tools for accessing the IBCAO modelGIS Tools for accessing the IBCAO model

ESRI: ArcView, ArcInfo (Spatial Analyst, Arc Grid)

Intergraph: MGE (Terrain Analyst)

Geomedia (MFworks from ThinkSpace Inc.)

Clarks Labs: Idrisi32

Caris: HIPS

Web GIS toolsWeb GIS tools

Intergraph: Geomedia Web Map

ESRI: ArcIMS3

Geophysical and Mapping softwaresGeophysical and Mapping softwares

IVS: Fledermaus

Public domain: Generic Mapping Tools

Regional grid models representing Regional grid models representing bathymetry/topography are often used as a base for bathymetry/topography are often used as a base for oceanographic/climate/geophysical/ice sheet modelingoceanographic/climate/geophysical/ice sheet modeling

The modeling results are often interpreted without The modeling results are often interpreted without knowledge of the spatial differences in reliability of the knowledge of the spatial differences in reliability of the underlying bathymetry/topography modelunderlying bathymetry/topography model

The idea is to create a grid with the same structure as the The idea is to create a grid with the same structure as the bathymetry/topography grid containing an estimate of the bathymetry/topography grid containing an estimate of the standard deviation of the errors of the standard deviation of the errors of the bathymetry/topographybathymetry/topography

THE NESSECITY FOR AN ERROR ESTIMATIONTHE NESSECITY FOR AN ERROR ESTIMATION

USING THE MONTE CARLO METHOD FOR USING THE MONTE CARLO METHOD FOR ERROR ESTIMATIONERROR ESTIMATION

Randomly vary the source data within Randomly vary the source data within constraints determined by meta data constraints determined by meta data (navigation, echo sounder etc)(navigation, echo sounder etc)

Go through the process with which the Go through the process with which the bathymetry grid is compiled (block median bathymetry grid is compiled (block median filtering + continuous curvature splines in filtering + continuous curvature splines in tension)tension)

1.1.

2.2.

This processes are continued until………This processes are continued until………

STATISTICSSTATISTICS

Run 1Run 1....

..Run nRun n

Standard deviation of estimated errorStandard deviation of estimated error (% of block median depth)(% of block median depth)

IBCAO contours in GeomediaIBCAO contours in Geomedia