Thanks for posting this dataset. However, it is a shame that you have not maintained the distinction between boundaries that have been agreed and boundaries that have yet to be defined. Users need to be aware that more than half of the world's maritime boundaries have not yet been agreed, and for these boundaries what the VLIZ dataset depicts is an approximate median line between the relevant coasts.

Many maritime boundaries do follow the median line, and in the absence of an agreed line, it is quite reasonable to show the median line as a potential boundary. However, states are certainly not bound to accept the median line and there are numerous examples of boundaries which depart significantly from it. It is therefore quite misleading to describe such lines as boundaries. I think that at the very least you should add a note to this effect - and, if possible, show agreed boundaries in a different colour from median lines.

Regards,

Martin Pratt
International Boundaries Research Unit
Durham University

Martin Pratt,

Your suggestion to differentiate treaty boundaries from medians using a different color is a good one which I shall undertake as my personal time permits. As noted in the postings, the underlying data source for this posting is that provided by the Flanders Marine Institute (VLIZ), which includes their documentation of the rationale and source(s) used for each boundary segment.

Outside of this posting, few if any other sources for these boundaries are available to the general public which are free, in high resolution, and do not require expensive application software (e.g., SHP files). Studying your Durham University Boundary-related links page, one notes,

• The Sea Around Us Project provides this data in very low resolution.
  
• Florida State University College of Law provides excellent detailed map coverage in JPEG format, but not global coverage.
  
• General Dynamics provides a database via CD ROM on an annual subscription basis, requiring ESRI software, both of which many users would deem to be expensive.
  

Perhaps your International Boundaries Research Unit would like to lend your expertise and assist in this effort as VLIZ undergoes changes in personnel and direction.

I only suggested colour-coding agreed boundaries and median lines because the VLIZ dataset already distinguishes between the two line types. The distinction is not readily apparent when viewing the dataset online but the type of line is displayed if you use the 'point query' tool. The downloadable polyline shapefile also classifies each line according to one of four types (Treaty, Median line, 200 NM and Disputed). Hopefully this will make it realtively straightforward to colour-code the lines in the GE dataset.

Thank you for the great GE overlay with the EEZ!!!

I have some suggestions for improving it:
1. some areas are displayed in the current map as joint, but are actually disputed (as far as I found information about it): Bajo Nuevo Bank and Serranilla Bank

2. currently displayed red line between Columbia mainland and Providencia islands - if there is some dispute about the islands by Nicaragua or Costa Rica then the lines between the respective state and the islands should also be red. As currently displayed with a single red line - it appears that there is dispute INSIDE Columbia regarding the administrative border between its sub-units.

3. joint areas display - it would be better if blue lines only on the sides sharing the joint area, yellow lines to the sides not participating (for example Indonesia/Timor/Australia: Indonesian sides of the Timor/Australia joint area should be yellow, lines between Timor/Australia - blue)

4. joint/disputed - names/links or disputes/joint areas

5. currently Antarctica has joint line as per the Antarctic Treaty. It would be usefull to include inside the blue/joint EEZ-line some red/disputed lines for the borders between the claims of Chile, Argentina, UK, Norway, Australia, France, New Zealand: http://en.wikipedia.org/wiki/List_of_Antarctic_territorial_claims
thus Antarctica outline will be blue as currently, but inside there would be red sectors showing the dispute/different claims

6. more layers to be added:
- archipelagic/internal waters (baseline)
- territorial sea (12nm from baseline or less if state does claim less)
- contigous zone (24nm from baseline or less if state does claim less)
(current layer: EEZ, 200nm from baseline)

- 350nm from baseline (extended continental shelf - rule1 - equal to 150nm from EEZ/current layer - thus this should be relatively easy to implement?)
- 100nm from 2500m isobath (extended continental shelf - rule2 - sea depth needed, thus this may be harder to implement properly, but at least best guess from the available data)
- de jure extended continental shelf - after the UNCLOS commission goes trough the submissions by the states

7. Bosnia/Croatia sea border missing (as small as it is ...)

8. It looks like the VLIZ database was updated in 2009 - I don't know if these updates are implemented in v3 here.

shelf1:

I'll be posting an update within a couple of months.

I'll address the first three points on joint areas and point 7.

On point 4, I suggest you follow the link in the thread for Multiligual support to get the names of each area.

Point 5 is questionable... I believe that the Antarctic Treaty overrides prior claims.

Point 6 requires data for which I have not located a public data source.

It is very good to hear that you are still working on this project!

Please, look at my additional suggestions:
9. disputed areas - same as joint - I think that only disputed lines should be red, the rest should be yellow (for example Western Sahara/Morocco - only the border between them/the existense of WSahara is in dispute, the outline is not disputed; the same is for many other cases - Japan/Russia for the Kurill islands - they dispute the ownership of the islands, thus the line(s) between Japan and Russia, not the outer borders of the Kurill-EEZ)

10. For the UAE/Iran disputed islands - currently the islands EEZ is marked red (because it is disputed), but between the islands and UAE there is one short yellow line - appearently Iran/UAE agreed border. Maybe it is just me, but it seems strange - if the islands would go to Iran, then its EEZ will merge with the islands EEZ and the area between the islands and this yellow line; if the islands would go to UAE, then its EEZ will merge with the islands EEZ, but then INSIDE UAE EEZ would become one enclaved Iran EEZ? Is this so, or this is just some drawing error?

11. I can't find a link showing that the Kazakhstan/Turkmenistan caspian border is agreed (yellow)?

12. It would be very usefull if you can bring back the inter-dependencies borders (for UK, France, US, etc. entities) - on a different layer that can be selected/unselected (thus reverting between the current view and view with more granular borders) - this is espicialy interesting for the EU members dependencies, because the EU fishing policy does not apply to all of them; also for Svalbard - becouse of its special status.

13. While on granularity - it would be nice if sub-national EEZs are added on another layer (I don't know, but maybe in the different US States there are different laws about EEZ utilization?) Anyway, as land borders are shown for sub-national entities (first level administrative divisions) it would be nice to have them extended to EEZ (this is sensible only for countries, where the law assigns EEZ to their sub-national divisions, because maybe there are cases, where the the EEZ is treated as national "entitiy" not assigned to any
sub-national division). Sorry, but I don't have enough data here.

5. About the Antarctic Treaty System - as I read on Wikipedia it seems that the ATS suspends the action of prior claims, but does not renounce them; the ATS signatories agree not to stake any future claims (with the exception of US and Russia); the ATS signatories do not recognise the claims - so they are actualy disputed, but the dispute is put on hold for the duration of the Treaty (IMHO). So, I think that blue line around Antarctica and red lines (straights over the meridians - the coordinates are in the wikipedia article - from the south pole to the blue line of Antarctica EEZ; only the Peter I island should have "round <=200nm EEZ") inside would be good representation of this situation (internal lines could be on a different layer). I will try upload such kmz-file here, but my GE skill is not very advanced, so my lines don't go to the blue EEZ, but to 60-S circle, because it was easier to do... Also, I coudn't make the Peter I EEZ).

Here is a quote from Wikipedia article linked above:
"It is sometimes stated that the Antarctic Treaty defers or suspends these claims. However, Article IV of the treaty, which deals with the issue of territorial claims, merely specifies that previously asserted claims are not affected by the treaty.
The Antarctic Treaty states that contracting to the treaty:
is not a renunciation of any previous territorial claim.
does not affect the basis of claims made as a result of activities of the signatory nation within Antarctica.
does not affect the rights of a State under customary international law to recognise (or refuse to recognise) any other territorial claim.
What the treaty does affect are new claims:
No activities occurring after 1961 can be the basis of a territorial claim.
No new claim can be made. [with the following exception:
Soviet Union and the United States both filed reservations against the restriction on new claims, and the United States and Russia assert their right to make claims in the future if they so choose.]
No claim can be enlarged."