EVS-Islands

If you follow my posts, you will know that Eiao Island has been mapped a few times before. Once using a hybrid series of Landsat and WRS images and another time using SRTM data. It was a good effort, but there was a problem with clouds obscuring a portion of the shoreline.

Using Digital Globe HiRes imagery with 0% cloud cover, Eiao Island has been definitively mapped. Not only is the shoreline mapped with exquisite detail, as you can tell with the 1:8,750 scale map and image, but vegetation is accurately plotted.

Now to explain the title of this post, Don't Blow This Island Up!. Eiao Island was selected and explored by the French Nuclear Agency and French military as the next Pacific test site for nuclear devices. I believe the plan was to drill into the island and ignite nuclear weapons.

Hasn't this island had it's fair share of troubles. Well intended sailors and erstwhile settlers released pigs, goats, cattle and sheep. These critters have eaten much of the native vegetation. Way back when (not sure of the date) the French used Eiao Island as a prison. The prison was finally abandoned and the island reverted back to it's pigs, goats, cattle and sheep.

Now the French want to blow the island up. Eiao Island does not deserve this sort of mistreatment. Fortunately, the island was spared. The French government bowed to world pressure to halt their work to prep this island for nuclear destruction. Still, it is overrun by pigs, goats, cattle and sheep, but the nuclear devices are no longer a threat, for now. Let's hope forever.

view Eiao Island on Google Maps

Enjoy!

Labels: Digital Globe, EVS, feral animals, France, island, Marplot, Marquesas, nuclear weapons, Pacific

Posted by Mr Minton at 3/26/2007 11:19:00 PM | Permalink | Comments | links to this post

Clipperton Island - Marplot Map Landsat Image from N-12-10_2000

It has been some time since I was able to post a completed island. It seems that Blogger is running a bit on the slow side. Anyway, here goes a new post. Clipperton Island is known as a great sport fishing destination. It is also home to a weird tale about a king and his unwilling court. You can find out about that story at other places on the Internet.

The map was a challenge to create. Using MARPLOT and non-copyright images, I was able to create the map. The Landsat image was very course. In addition, cloud cover obscured parts of the island. Through mapping dilligence and keen eyesight, I was able to complete the above project. I think it looks just fine.

Enjoy!

Labels: atoll, EVS, France, Global Mapper, island, map, Marplot, Pacific

Posted by Mr Minton at 12/21/2006 08:45:00 AM | Permalink | Comments | links to this post

Tikei Island - Landsat Image S-06-10_2000 (1-25,000)

Tikei Island - Marplot Map (1-25,000)

Tikei Island (14˚58'S., 144˚33'W.) is a small island about 60 miles NE of Aratika. The only landing place is at a small village on the W extremity of the island, and it is difficult. (SD Pub-126)

Tikei Island is a poorly researched island. It is not a typical Tuamotu atoll, but an island. It is a low island that most likely was an atoll many millions of years ago. The lagoon is gone and the island is covered with heavy vegetation.

Enjoy!

Labels: atoll, EVS, France, Global Mapper, island, Landsat, map, Marplot, Pacific, Polynesia, Tuamotus

Posted by Mr Minton at 12/16/2006 03:09:00 PM | Permalink | Comments | links to this post

First some facts about this small atoll. According to a 1994 Franco-Australian Expedition the lagoon contained within is hypersaline (real salty). Yet, it contains "a high diversity of fish". The theory is that high waves push ocean water into the lagoon bringing in zooplankton and other oceanic fish. In another article from this same expedition the zooplankton within the lagoon was found to be different from the zooplankton found in the ocean off-shore. This would seem to confirm that the lagoon is almost completely isolated from the ocean.

Due to it's uniqueness, Taiaro Atoll is part of the Tuamotu Biosphere Reserve. It, along with five other atolls within the Fakarava Municipality makeup this protected area. The above referenced link also contains a few photos from the atoll.

Finally, there is a copy of a report issued by the 1994 Franco-Australian Expedition that gives the curious reader detailed information about the closed life cycle for some coral fish within the Taiaro Lagoon.

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This project took about six hours to complete. I elected to digitize using Google Earth/Digital Globe imagery at 1:1-meter. The resulting map is highly detailed and attempts to make accurate on-land layer determinations. The southern end of the atoll was the most challenging. The reef in this area is complex and difficult to determine whether features are above or below water. This is where "local knowledge" would serve to make the best final layer determinations. Perhaps one day I will make that trip to my mapped islands to provide that "local knowledge" my projects require. Until then, this will have to do.

Enjoy!

Labels: atoll, Digital Globe, EVS, France, Global Mapper, Google Earth, island, Landsat, map, Marplot, Pacific, Polynesia, Tuamotus

Posted by Mr Minton at 12/16/2006 10:11:00 AM | Permalink | Comments | links to this post

Makatea Island - Marplot Map with Contours North (1-31,250)

Makatea Island - Marplot Map with Contours South (1-31,250)

Makatea Island is an old project.  It is also an island that generates alot of interest.  I think the reason so many of my visitors view this island is because it is one of the few high islands within the Tuamotus.

Having recently discovered the ability to quickly create contours using SRTM data, I decided that Makatea Island could use contours. I downloaded the appropriate SRTM tile and loaded it into Global Mapper.  I then zoomed into the island, selected "Create Contours", selected 20 meter intervals, pressed "Enter" and created the contours.

The contours created on the northern end of the island extended into the ocean.  I had to reshape them to fit into the actural shorelines.  It seems to be a problem with SRTM data.  Or it could be a problem with footing SRTM data with Landsat ETM+ imagery.  Seeing that 95% plus of the contours appear to be plotted where they might belong and the problem of contours extending into the ocean is typically located along a small portion of the shoreline the problem seems restricted.  I really need to explore it in greater detail before I determine the causes of the problem.

The Maketea Island map with contours is good.  Those of you that require contours for this island, know that I have them and will share them.  Just drop me a line and I'll fix you up with any of the layers you might require.

Enjoy!

Labels: atoll, EVS, France, Global Mapper, island, Landsat, map, Marplot, Pacific, Polynesia, SRTM, Tuamotus

Posted by Mr Minton at 11/28/2006 09:52:00 PM | Permalink | Comments | links to this post

Reitoru Atoll (17˚50'S., 143˚06'W.), a low atoll, has no en-trance into the lagoon.

(SD Pub-126)

More information about Reitoru Atoll can be found at an interesting link that gives some facts about the very small population that makes a living from pearling.

This is the finished map with vectors taken from the Google Earth 1-meter resolution image. The map took about four hours to complete. It is a very solid effort.

Enjoy!

Labels: atoll, Digital Globe, EVS, France, Global Mapper, Google Earth, island, Landsat, map, Marplot, Pacific, Polynesia, Tuamotus

Posted by Mr Minton at 11/24/2006 10:05:00 AM | Permalink | Comments | links to this post