EVS-Islands

Raivavae Atoll - Digital Globe Image in Google Earth

Raivavae is a gorgeous atoll located in the South Pacific. It is also imaged by Digital Globe's satellite. I love the tour function within Google Earth (GE) - plot a path, control the speed, altitude and direction. With that in mind I decided to take a shoreline tour of Raivavae Atoll. The tour's focus is the shoreline of the central island, the high island. So let's go exploring!

First you need to download the tour. It is in KML format and is called RaivavaeAtoll.kml. You must have GE installed, open the Raivavae file and it will load into an area called Temporary Place, located in sidebar. Prior to running the tour setup Tools to tour at a nice speed.

Google Earth Options - 3D View Tab

Google Earth Options - Touring Tab

Set up your 3D View tab and Touring Tab as the above to images show.

Raivavae Atoll - Places Sidebar

Open the Raivavae Atoll file, select the Central Island Shoreline Tour folder. Uncheck the file and the irritating placemarks will not appear. Now put some romantic music on, set back, select the tour button and enjoy the Raivavae shoreline.

view Raivavae Atoll on Google Maps

Enjoy!

Labels: Digital Globe, Google Earth, Raivavare Atoll, tour

Posted by Mr Minton at 4/28/2007 03:37:00 PM | Permalink | Comments | links to this post

Caspian Sea - Marplot Map with Isobats (1:65-km)

The last couple of evenings I converted Caspian Sea isolines into isopolygons. Each color of blue represents another depth. The deepest point within the Caspian Sea is in the southern portion at over -900 meters. Just to the north of that depth is a stretch of sea floor from Baku, AZ to the Turkmenistan shore that is loaded with oil. It is an area that has been worked extensively and continues to be explored and exploited.

Caspian Sea - Marplot Map with Isobats Detail Middle (1:16.25-km)

Caspian Sea - Marplot Map with Isobats Detail North (1:32.5-km)

The northern Caspian Sea is another area of extraordinary oil deposits. It is very shallow (5-meter or less). The problem with the oil throughout the Caspian is getting it shipped to market. The oil currently flows through pipelines into Russia and another newer pipeline that will transport the oil into Turkey. The Caspian Sea has lots of oil, but it is difficult getting the oil into western markets.

The biggest challenge with this project was determining the colors to use within the various isopolygons. I believe the colors you see here provide a solid presentation. However, Marplot is rather weak on labels.

Caspian Sea - Marplot Map with Isobats Detail North with Labels (1:16.25-km)

For the most part, the labels show up and are readable, but quite often they get swallowed by a layer of information. I could apply labels as a separate layer of information. I would do that if this map were a commercial product, but since it is my product for my enjoyment, I'll leave the labels as they are.

view the Caspian Sea on Google Maps

Enjoy!

Labels: bathymetry, Caspian Sea Environment, Global Mapper, isobats, map

Posted by Mr Minton at 4/23/2007 10:06:00 PM | Permalink | Comments | links to this post

Rapa Iti Island - ISS Image ISS004-E-12979

Rapa Iti Island - Marplot Map with 50-m Contour Intervals (1:60,000)

Finally, I'm going to put this project to rest. My first post about this island happened back in July 2006. I was new to mapping contours and did not attempt it with this project. In March 2007 I commented on voids that occur within SRTM data. The voids contain no data and consequently, no contours are generated for these area. The above Marplot map contains 50-meter contour intervals for the entire island. The SRTM data I used (SRTM_08_18.asc) comes from CGAIR. It is reworked SRTM data with voids filled, whenever possible.

Rapa Iti Island - Shuttle Image with 50-meter Contour Intervals (1-15,000)

Rapa Iti Island - Marplot Map with 50-meter Contour Intervals (1-15,000)

The above two images show how accurate these contours are. I wouldn't want to build a house based on them, but I would hike around and over the island using them.

Rapa Iti Island - Marplot Map with Ha'urei Harbor Detail (1-30,000)

This final map shows the fine harbor and anchorage on this island. The community is called Ha'urei. It is home to the 126-voice Tahitian Choir. There is an NRP segment that plays some of the music and talks with the musicologist about his recordings. Wikipedia has alittle information about the island as well. My original post of July 2006 has a good deal of information about this island.

view Rapa Iti Island on Google Maps

Enjoy!

Labels: Australs, Bass Islands, EVS, Global Mapper, island, Landsat, map, Marplot, Shuttle Image

Posted by Mr Minton at 4/23/2007 12:17:00 AM | Permalink | Comments | links to this post