EVS-Islands

I am resubmitting this post with a new addition. Instead of the lengthy process I had to follow in Excel, this new process requires a download of GE Path, a nifty piece of software that allows you to work with lines or polygons outside of Google Earth. I use it to move my KML file into an Excel spreadsheet. In Excel I delete a couple of columns, move a column and rename and finalize the data. I can then move it out of Excel and into almost any mapping program around. It is a slick process for all those souls that do not have KML/KMZ import/export capabilities in their mapping software. If you do have the ability to import/export KML/KMZ files, never mind.

This is a very popular post with my readers. If you have difficulties reading the Flash presentation, go directly to my Flickr account and check out the set of images with the same name as the title of this post.

Posted by Mr Minton at 8/18/2006 11:20:00 PM | Permalink | Comments | links to this post

The following is from Wikipedia,

Groupe Acteon consists of four low-lying atolls. They are a part of French Polynesia.

Matureivavo (21˚29'S., 136˚24'W.), the largest atoll within the Acteon Group. It is about 4 miles long in a NNW-SSE direction and is high enough to be visible from a considerable distance, and gives the appearance of a sandy beach, backed by a line of dark green. Some buildings lie on the NW side of the atoll. In bad weather, the seas sometimes sweep over the reef. There is no entrance to the lagoon.

Tenarunga (Tenaruga), 15 km NNW of Matureivavo, is a low, wooded and uninhabited atoll in the Actaeon group in the southeastern part Tuamotu Islands. Tenarunga, like the rest of the Actaeon group, belongs to the municipality of the Gambier Islands. The lagoon is not accessible from the sea.

Vahanga (21˚19'S., 136˚39'W.) a small atoll 5 miles W of Tenaruga, is covered with coconut trees. There is a landing place on the NW side of the atoll, near a white house, but there is no access to the lagoon.

Tenararo (21˚18'S., 136˚44'W.) the smallest of the group, has a landing place on the NW side of the atoll between the small boulders, which encumber the reef. There is no entrance to the lagoon.

Information taken from Sailing Directions, Pub 126, "Pacific Islands" NIMA 2002; page-12

This was a project that I completed many months ago, but decided to revisit using my new format. The difficult part was to gather all of the screen shots together, edit them, Flickr them into a set and finally to fashion this post. It took the better part of the morning. Enjoy!

P.S. - This post was done using Widows Live Writer Beta. It was easy to use and offered a great deal of control over the final output.

Enjoy!

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

Posted by Mr Minton at 8/17/2006 02:35:00 PM | Permalink | Comments | links to this post

If you've followed my recent posts you know that there is a great deal of interest in the NGA PGS map product.  I had earlier reported that EarthSat had worked 300 man-years on the map files.  According to my source, that number was not accurate.  The individual I had spoken with had miscalculated.  In actuality, they spent 13 man-years on the project.  That is still a tremendous investment in time and effort.

To keep my readers abreast of my efforts relating to this database, I do have the NGA PGS database, all 28-files, loaded into my mapping program, Marplot.  I use them exclusively when I am working on projects at 1:125,000 and larger.  I move portions of them into Global Mapper and Google Earth Plus when I am digitizing shorelines and I require a frame-of-reference.  The details that are available in the NGA PGS data are excellent.

I have also converted the Region-6W of the NGA PGS data into KML/KMZ, Google Earth (GE) format, and posted it to GE.  It looks great on GE often turning some of their blurry images of islands into recognizable shapes.  See my post entitled, How To Convert PGS Map Files into KML/KMZ.  I also do comparisons of various shoreline map files, Comparison: PGS, WVS, EVS and 1-Meter Shorelines.

I am sure most of you are aware of my push to take the NGA PGS data to the next level, what I call Enhanced Vector Shorelines or EVS.  My post entitled, How To Adjust PGS to EVS Precision - An Example and Thoughts, discusses how to make the adjustments and concludes with my ideas on how this might happen for the entire data set, that is converting PGS to EVS precision.

I know that EVS precision is cartographically sound based on a side-by-side comparison I recently completed using  a Land Information New Zealand topographic map and my own EVS version of the same island (Palmerston Atoll).  At a scale of 1:25,000 the LINZ map and EVS map are nearly identical.  This leads me to conclude that EVS precision can often result in a map product useful at 1:25,000 scale.

I am adamant on two points regarding the NGA PGS map files:

1) They are, without question, the most precise representation of global shorelines available to the public.

2) Realizing that they are Prototypes (needing refinement), PGS should be refined to EVS precision in order to provide the most accurate, finished shoreline possible, derived from Landsat-7 ETM+ 2000 imagery.

So goes my quest to make this refinement a reality.

Posted by Mr Minton at 8/16/2006 09:59:00 AM | Permalink | Comments | links to this post

Temoe (Timoe) (23˚21'S., 134˚29'W.) is 3.5 miles long and 2 miles wide. Its barrier reef has several islets planted with coconut palms.

The Crescent Island Saga

Below the ebay listing of acrylic money from Crescent Island, is the story of Crescent Island and Temoe Atoll figures in.

Enjoy!

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

Posted by Mr Minton at 8/13/2006 10:00:00 AM | Permalink | Comments | links to this post