Tuesday, June 30, 2009

Robinson Crusoe Island CL - When This Old World is Getting You Down or Two Other Maps

Robinson Crusoe Island - Wagner IV World

Robinson Crusoe Island CL


Robinson Crusoe Island - Landsat ETM+ S-17-30_2000 (1-85,000)

Robinson Crusoe Island - Landsat ETM+ S-17-30_2000 (1:85,000)


Robinson Crusoe Island - DigitalGlobe Image from Google Earth

Robinson Crusoe Island - DigitalGlobe Image from Google Earth (1:85,000)


Robinson Crusoe Island - EVS Precision Map (1-85,000)

Robinson Crusoe Island - EVS Precision Map (1:85,000)

When This Old World is Getting You Down

At times we all wish we could pull a "Robinson Crusoe", find some forgotten spot, seldom visited, yet replete with all the necessities of life - food, water, clothing and shelter. A place without financial pressures, martial woes, busy urban scene and no threat of crime spilling into our fragile lives. I'm not sure that place exists. Alexander Selkirk, the individual Daniel Defoe based his Robinson Crusoe character on, was so lonely by the end of his four year exile, he gladly rejoined the crew of the individuals who had originally abandoned him. His life on previously uninhabited Isla Mas a Tierra was often wretched. His diet was life sustaining, but challenging to gather. His clothing was handmade and unkept. His shelter is reputed to be a cave. He spent many lonely hours at his lookout scanning the horizon for a ship that might rescue him.

With that said, we still wish we could escape to his place. We all know in our heart of hearts we would do better. We would not grow lonely, but using our 21st century knowledge and preplanning, our island life would be a special time to reflect on the world and all of its mysteries and how we fit into them. When we grow tired of our adventure, we would merely dial our satellite phone and be whisked away, back to our previous lives.


Rob-cru

Robinson Crusoe Island - Wikimedia Commons


Mapa

Robinson Crusoe Island - Source Unknown (1:120,000)

Two Other Maps

A map is seldom an entirely unique creation. Robinson Crusoe Island has been mapped many times. Some of these are excellent compositions. I used two other maps to aid in the construction of my map. The first one, found in the Wikipedia article on Robinson Crusoe Island was used to gather feature names. The second map, source unknown, was used to confirm certain feature names and supply any new ones not found on the first "helper" map.

The vector files making up my EVS precision map were created using Landsat ETM+ and DigitalGlobe from Google Earth. The majority of the shoreline was extracted from DigitalGlobe imagery. Where clouds obscured the land, I used Landsat to map the underlying area. The 50-meter contours were derived from SRTM data. There is a problem with the elevations, some of the higher elevations are dramatically different than what they should be. El Yunque Peak is supposed to be 913-meters, but is shown to be approximately 650-meters using SRTM data. I did not correct the erroneous elevations in this version of my map. Perhaps, I'll correct them later.


5410

Robinson Crusoe Island - Chilean Nautical Chart 5410 (1:50,000)

Finally, for all of you sailors that wish to explore Robinson Crusoe Island, the Chilean Hydrographic Office (SHOA) has a nautical chart you might wish to purchase. The above image is a copy of it.

Enjoy!

Thursday, June 18, 2009

Thoughts - How Many Uninhabited Islands in the World?

First one must define island. According to the United Nations Convention on the Law of the Sea Part VIII:



1. An island is a naturally formed area of land, surrounded by water, which is above water at high tide.


2. Except as provided for in paragraph 3, the territorial sea, the contiguous zone, the exclusive economic zone and the continental shelf of an island are determined in accordance with the provisions of this Convention applicable to other land territory.


3. Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf.


Now how about nations with lots of islands? Let's list those: Sweden 221,800; Finland 179,584; Canada 53,000; Norway 50,000; Indonesia 17,504; Philippines 7,107; Greece 6,000; Japan 3,000 and Maldives 2,000. In just these nine island rich countries, over 500,000 islands are accounted for. Now for the good news for all of you folks that want to find your own uninhabited island. That place where you can get away from all of the worries of the world - an uninhabited island. Of the 500,000 islands located in these nine countries, only 11, 000 (2%) have a permanent population. That leaves 539,000 (98%) mostly very small islands that have zero population. So take heart all of you Robinson Crusoes, there is an uninhabited island just waiting for you to claim it.


Enjoy!

Wakhjir Valley & Pass AF - Marco Polo Sheep, Silk Road & A Lengthy Mapping Project

Wagner IV World

Wakhjir Valley & Pass AF


Wakhjir Valley and Pass - EVS Precision Map N-43-35-2000 from Landsat ETM+ N-43-35-2000 (1-100,000)

Wakhjir Valley and Pass - EVS Precision Map N-43-35-2000 from Landsat ETM+ N-43-35-2000 (1-100,000)

This map is the culmination of over two weeks of digitizing glaciers, meandering streams, high mountain meadows and many hours of research. During the researching phase I learned about the Great Game, Marco Polo sheep and the Hindu Kush, Pamir, Karakoram mountain ranges. I learned that this valley is an offshoot of the primary valley, the Wakhan that slices between the Pamirs to the north and the Hindu Kush to the south. At the Wakhan's eastern terminus, one could head into the Wakhjir valley and cross over the Wakhjir Pass into China or one could continue east to northeast into Tajikistan and eventually into China. I have always liked the path less traveled, so I elected to study and map the Wakhjir Valley and Pass, a trekkers paradise.


Wakhjir Valley and Pass (Russian Topo J-43-101) Modified

Wakhjir Valley and Pass from Russian Topo J-43-101

First in conducting research, I discovered a site, Poehali!, offering 34,727 free Russian topographic maps (1:100,000). Not only do they offer the topos, but a corresponding MAP file to facilitate georectification. Like a kid in a candy story, I downloaded 11 topos with MAP files. I'm not the greatest at reading cyrillic, but using Google Translate, while comparing the topos to both Landsat ETM+ N-43-35-2000, which covers all of my target area and Google Earth imagery, I was able to make sense of the written data included on the topos.

During my study of the topos, I determined that the Russians had digitized the international borders with a greater accuracy than any of my border sources. Using their topos as base imagery, I digitized new international borders for this area.

The 100-meter contours were generated using void filled SRTM files and Global Mapper. They took about 30-seconds to create once all of the necessary files were loaded. The Russians used 40-meter contours. I think that is overkill. So I elected 100-meter contour intervals.

See all of the glaciers, meadows and streams? That's what took many hours to digitize. All of this data was taken from the Landsat ETM+ N-43-35-2000 imagery. It is virtually cloud free and snow free leading me to believe the imagery was taken during the short summer. It was a matter of how detailed I wanted my map to be. The glaciers were tedious to digitize. I was able to map all glaciers and snow banks that were imaged. The streams were the easiest to map and the least accurate. Landsat, at 14.5 meter resolution, makes that mapping difficult. If the streams/rivers branched, I created a layer called meandering riverbed. My final polygon layer high mountain meadows. The people living in this part of the world are herders. These mountain meadows are critically important as food for their domesticated animals, sheep and goats. These mountain meadows consisted of the lime-green colored vegetation layer located along the valley floors. Needless to say, these three polygon layers were challenging to map and time-consuming to digitize. I wanted to stop and move on to an island, but I counldn't bring myself to do it. Today, I am done! The map can still use work, but I am done.


Wakhjir Pass - Google Earth Pro Image Modified

Wakhjir Pass - Google Earth Pro Image

The above image shows the climb one would need to make in order to get to the pass and cross into China. Apparently, Marco Polo is reputed to have crossed at Wakhjir Pass on his historic trip into China. On the way he recorded a description of the sheep that takes his name, the Marco Polo sheep


Marco Polo Sheep

Marco Polo Sheep (picture from Snow Leopard Conservancy)

Their numbers are dwindling due to lose of habitat, over hunting and weather extremes. George Schaller has worked tirelessly to save these endangered animals. He would rather not have these majestic animals hunted, but if they must be then the hefty fee of $25,000 per hunt, should be used to benefit the people of the Wakhan. He also is working to establish a 50,000 sq kilometer multinational park that will go far in protecting the Marco Polo sheep and their unique habitat.

Finally, for all of you visiting my site expecting to see my latest island map, I apologize and will endeavor to remedy the situation. For all of you who appreciate a nice map, select the top map image and see the map at full size. Pretty cool, huh?

Enjoy!