The Marine Geoscience Data System provides online resources for exploring ocean mapping data including the Global Multi-Resolution Topography Synthesis (GMRT), GeoMapApp, and the Marine-Geo Digital Library. The GMRT is an open-access global digital elevation model of ocean bathymetry and lands at varying resolutions. It is compiled from over 800 cruises and updated biannually. Data is accessible through web map services, desktop and web applications. The Marine-Geo Digital Library archives over 600,000 data files and links them to publications. These resources support both specialists and non-specialists in visualizing and accessing ocean mapping data.

1. The Marine Geoscience Data System
and the Global Multi-Resolution
Topography Synthesis:
Online Resources for
Exploring Ocean Mapping Data
John Morton, Vicki Ferrini*, Suzanne Carbotte,
and the MGDS Team

2. MGDS Tools & Services
• GMRT Synthesis
• GeoMapApp
• Marine-Geo Digital Library
Specialist
Non-specialist

3. GMRT Synthesis: Overview
• Open-access global elevation product
– Focus on bathymetry
• Support specialists & non-specialists
• Multi-resolutional synthesis
– GEBCO_2014 + MBES + land + grids
– MBES at full-native resolution (100m+)
• Tiled Global Compilation
– Images, grids, mask
– Mercator, South Polar, North Polar
– 2 scheduled releases / year
(~80 cruises)
• Attribution to data contributors
• Access to source data
• Multiple Apps for Access

4. Multibeam Data* Preparation
• Bad navigation
• Noisy outer beams
• Attitude problems
• Bad soundings
• Instrument problems
• Bad weather
• Sound velocity
• Attitude Offsets
• Slow speed in turns
• Grid weighting
• Resolution (100, 50, 25 m)
*LDEO team processes swath files (public domain, primarily US Academic)

5. • Compilation began in 1992
• Includes data from 1980 - present
• Current version of GMRT (v.3.1, Nov. 2015)
• 875 Cruises
• > 4.4 Million trackline km
• > 175K processed swath files
• 28.6 Million km2
(~8% ocean)
Multibeam Data in GMRT

6. GMRT Access
• GMRT MapTool
• Web Services
• GeoMapApp
• Earth Observer
• Partner Products
(MB component only)
– Google Ocean Basemap
– Esri Ocean Basemap
– GEBCO 2014
http://gmrt.marine-geo.org

7. GMRT MapTool
http://www.marine-geo.org/tools/GMRTMapTool/

8. GMRT – Web Services
• Web Map Services
– Mercator
• masked, un-masked, track-lines
– South Polar
• masked, un-masked, track-lines
• RESTful Web Services
– GridServer
– ImageServer
– PointServer
– ProfileServer
– Attribution Service

9. • Desktop Java Application
• Core capabilities
– Grids/images, tabular data (plot, interrogate, interact)
– Load data, save sessions
• Access to 1000s of datasets
– Bathymetry, Bottom Photos,
Sidescan & more!
– Links to original data sources
• Custom Portals
– IODP, Seismic, Trackline geophysics, Photos
GeoMapApp

10. GeoMapApp

11. Grid Functionality

13. Marine-Geo Digital Library
• Interactive Digital Library
• > 670,000 files from > 2,600 programs
• Field data + Derived Products
– Bathymetry, Photos, Interpretations
– Ships, submersibles, towed platforms
• Links to Publications
• Data Portals
• Data DOIs
• Analytics

14. Marine-Geo Search
• Map/Text search
• Multiple parameters
– Device, Data Type, Investigator, Date,
Spatial Extent, Platform, Publication, etc

15. Select/Download

16. Next Steps…
• GMRT
– More content!
– SP rebuild (underway)
– NP rebuild/web services
– Derivative products (e.g. Rugosity)
• GeoMapApp
– Enable functionality in web-interface
• Marine-Geo Digital Library
– Enhance map interfaces
– Display/access of data file content