Home > 2. Marine GIS > 2.9 Marine Regions
|1. Open the Marine Regions website and spend some time reading about this project|
|2. Along the top
margin you'll see these 5 tabs to access the data. None of these
"views" of the data are unique, and there is considerable overlap between
them; these portals just provide easier, thematic access.
Whatever you want in the way of global basemap data, they are here. Just take the time to find them.
GAZETTEER. From the tabs along the
top, you can use this tab to access a huge collection of shape files via:
|4. Click on the letter L, for example, to see a long list of feature names beginning with L.|
|5. After some digging down
into the list, you can find LIBERIA (NATION).
Alternatively, step back and type Liberia on the search bar.
|6. Click on LIBERIA (NATION) to see these metadata items about the available map.|
|7. Just below the above data, you'll see this map of Liberia. And there's a data download link.|
|8. There are many
data formats for this map, but it gives us a good chance to see the GML3
format (Geographic Markup Language, Ver. 3; GML). So click on the
DOWNLOAD link to see the actual file. Everything is too small to read
here, but we wanted you to see that GML is an ASCII XML-type file. The
data points are a huge block of lines after all the header information.
|9. Use FILE > SAVE AS and navigate to the folder PROJECTS > LIBERIA > DATA > BASEMAP > BORDERS > MARINEREGIONS and save it with the filename liberia_marineregions.gml or liberia_marineregions.gml.xml. The XML extension is optional.|
|10. Run Saga.
NOTE: Here you see it with the author's new preferred setup, with the settings panel on the left./
|11. Select TOOLS >
IMPORT/EXPORT-GDAL/OGR > IMPORT SHAPES
Then click OK.
|12. This polygon shape loads.|
|13. Use ADD TO MAP to see the polygon.|
|14. Examine the edges, for example the extreme southeastern point, to see that it is obviously a very low-resolution, utility file.|
|15. So the country files in this website are roughly the same low resolution as our familiar World Borders data.|
|16. MARITIME BOUNDARIES: From the tabs along the top, you can use this tab to access a complete collection of all national boundaries and a host of subsidiary areas, as you see here. To see how it works, select LIBERIA from the list of "sovereign" areas. Then click SEARCH (just below it)||
|17. This page of information appears about Liberian data, and data it shares with its maritime neighbors.|
|18. Here is the Liberia EEZ
alongside all its neighbors.
NB: " The EEZ of Liberia has been calculated without treaty available. Depending on which GIS software you use, this boundary can differ slightly" [VLIZ]
|19. Select the GML link for download and saving.||
|20. Navigate to the folder DATA > BASEMAP > BORDERS > MARINEREGIONS and save it with the name shown here. Make sure you use SAVE AS TYPE > ALL FILES so Windows won't add a different extension.||
|21. Here Saga has used its GDAL/OGR import routine (as you saw above) to load the display the EEZ polygon (green) with the national borders polygon (red).||
|22. If you save the EEZ polygon as a shape, then you can save the whole map (i.e. both polygons) as a Saga project file (*.sprj) for easy redrawing. SPRJ files can't contain GML files yet, so the shapefile conversion is needed.|
|23. What about the QUERY DATABASE BY COORDINATE section? If, for example, you know a particular location on the globe, as a longitude/latitude pair, then you can enter the coordinates here to see if you are in somebody's EEZ. This would be quite useful for planning cruises and instrument installations. By international law, you should even ask permission to take water samples inside somebody else's EEZ.|
From the tabs along the top, you can use this tab to access a collection of
the principal global datasets. Of course, this overlaps with the
previous access methods.
For example, click on MARINE ECOREGIONS OF THE WORLD (MEOW)
|25. This page opens, describing MEOW, with a global map. It's not easy to read here, but we wanted to show you a good example of the level of detail available.||
|26. Click on GO TO THE
WEBSITE to get
the vector data for the polygons, click in DOWNLOAD.
|27. Navigate to the folder DATA > BASEMAP > BORDERS > MARINEREGIONS and save the file as marine_ecoregions_world_marineregions.zip|
|28. Whether the contained
vector data are shapes or GML, you know now how to unzip them and load into
Here's the global polygon presented with ADD TO MAP in Saga.
|29. You can use the ACTION tool and
the ATTRIBUTES tab to see the metadata about any polygon. Here the
area offshore Liberia has been selected (shown in red).
You can see that most of Liberia's offshore area is within TROPICAL ATLANTIC > GULF OF GUINEA > GULF OF GUINEA WEST. Biologists can ponder over the consequences of this assignment.
|30. There is a huge selection of mapping schema you can collect for your purposes. Take your time to go through the global collections list, and save whatever you need now. Older version of MDL exercises added many of them to the project area map, but you don't need to do this now, just as long as you know how to do it.|
31. STATISTICS: From the tabs along the top, you can use this tab to access a compendium of data about the data presented here. "At the moment the Marine Regions lists and provides geographical relations on more than 71,288 place names, representing 57,307 marine geographic places. The scope of Marine Regions is global, but there is at the moment a geographic focus on European, North American and Antarctic marine waters. " [From VLIZ] This excellent map gives you an idea of the enormous scale of this project.
From the tabs along the top, you can use this tab to access a final
summarization of the major, global shapefiles available. [This single page
used to be the focus of this whole MDL exercise.]
To build your own complete collection of all EEZ's, click on the MARITIME BOUNDARIES V10 link.
|33. This list of maritime
boundaries files appears. It is
important to note here that prior to the magnificent efforts of VLIZ, the
only source of these data was a commercial CD that cost thousands of dollars
and required a $500/year updating service.
Click in DOWNLOAD at World EEZ v10.
You must also fill in a request form and submit.
|34. Whichever version you
requested, the folder will contain these files:
|35. Here's a map of the two datasets, showing the difference.|
|36. So this give you a good introduction to the amazing MarineRegions resource collection. You should, of course, work through it on your own, with a view toward areas and scientific topics of personal interest. Good luck.|
|37. As always, make sure to save any vectors as shapefiles if you want to reopen them easily as Saga projects. Also, either use the long filenames recommended here, or make up your own that might make more sense to you. Then apply these names in Saga and use them for the saving. It's terrible to work all day on a great map and then not be able to find it later due to name problems.|