Saturday, February 23, 2013

Clipperton Island FR - It Has Been a Long Time Between Maps and Why.

Clipperton Island - DigitalGlobe from Google Earth 
Clipperton Island - DigitalGlobe Image taken from Google Earth

Clipperton Island - EEVS Map (1-17030) 
Clipperton Island - EEVS Precision Map (1:17030)

Taking advantage of DigitalGlobes hi-res imagery found in Google Earth, I was able to redo my original EVS precision map of Clipperton Island into an EEVS (Extremely Enhanced Vector Shoreline) precision map.  Clipperton remains a popular, but long-distant fishing destination for long range boats from San Diego, my home town.  It is also one of the only French possessions located in the Pacific Ocean.  Besides the fishermen, DX'ers love to transmit and receive QSL's from this remote atoll.

I have been a busy map maker these past four months. My day job, as many of you know, is a middle school teacher. That means that every weekday I attempt to teach meaningful Social Studies lessons to a room full of less-than-eager students. This year I am trying something different, I teach Social Studies lessons using both Google Earth and Quantum GIS mapping software.

For example, my 6th grade students have just begun a unit on China.  As an entertaining but hopefully, useful exercise, I listed 15 cities, tourist locations, landmarks, etc., found in China.  The students had to locate them in Google Earth, take a screen shot, id the image, place it in a folder on their virtual desktop, and when complete submit the folder to me using Shared Documents.  My objectives - students get an introduction to the geography of China, they use Google Earth as a learning tool, they enhanced their image handling skills, and they have fun with geography while learning.

We will work with QGIS (Quantum GIS) during this unit.  I always like the students to create a vector layer of information on top of a georectified image.  This sort of project requires a great deal of patience and usage of a teaching method I call the "Louder Method".  If they don't get it the first time, just say it louder the next few times.  I'm just kidding.  Really.  REALLY!!

Enjoy!

Samana Cay BF - Columbus' First New World Landfall?

  Samana Cay - Landsat ETM+ Image N-18-20_2000 (1-85,000) 
Samana Cay - Landsat ETM+ Image N-18-20_2000(1:85,000)
 
Samana Cay - EVS Precision Map (1-85,000) 
Samana Cay - EVS Precision Map (1-85,000)
 
My interest in Samana Cay was the result of a serendipitous moment.  A few evenings ago while editing my Islands of the World point file, I became curious about the Turks and Caicos Islands.  Using my GSHHS World Shoreline map, I located the Turks and Caicos Islands.  Not an area I have done much mapping in, but interesting.  To the northwest was a small island off by itself, Samana Cay.  Nothing particularly outstanding, just a nice little island facing the Atlantic Ocean.  Curious soul that I am, I checked out the Wikipedia article and Wow!  Some scholars think this might be the site of Christopher Columbus' first landfall in the New World.  Pretty cool.

I identified the Landsat ETM+ mosaic, loaded it into Global Mapper and began mapping.  The completed map is nice.  The Landsat image is pretty cloudy.  More research and my next Wow!  Samana Cay is the largest uninhabited island in the Bahamas.  An uninhabited island close to home (USA).  How cool.

All of you Florida readers hunting for your Crusoe Getaway, Samana Cay could be your island.  People from Acklins Island visit periodically to collect cascarilla bark.  Other than the occasional Acklins Island visitors, you could be all alone contemplating whatever it is you want to contemplate.

Enjoy!

Thoughts - Quantum GIS, Africa and 6th Graders, A Recipe for Mapping Success.

QGIS West Africa Map

If you have followed my posts you know that I do most of my mapping work in Global Mapper, a solid mapping program that is easy to use and handles very large format image files with ease (Landsat, SRTM, GeoTIFF). However, it costs real dollars. Big bucks for me and unaffordable bucks to outfit each student workstation with a mapping package.  I have spent the last year learning how to make maps using Quantum GIS (QGIS), a well-maintained and powerful open-source mapping package.

I teach middle school students between the ages of 11 to 14, social studies which includes world history, US history and geography. We spend a good deal of time working with open-source software (OpenOffice, Irfanview, Audacity, etc.) to learn about our world and how to make effective use of technology in the classroom. I have always wanted to bring mapping into the classroom. This year I decided to give QGIS a try with my students. I was determined to teach my students how to identify and display spatial data on a map. That brings me to the West Africa map and QGIS..

This year all of my students are learning to make maps. They have learned the difference between vector files and raster images. They are becoming adept at labeling countries, cities, empires and city-states. They love to use all the wrong colors and fonts, but I let them because they are having fun making maps.  So far the projects have been relatively simple, but challenging in a mapping sort of way.

Today, my 6th graders (11-years old) were identifying and labeling countries in Africa using QGIS and a variety of vector files and a large format raster image of Africa taken from the Natural Earth website. They finished the country identification phase of the mapping project and wondered what to do next. I said, "Make a capital city point file and identify and label African country's capital cities."  In the past, I would have labored long and hard to teach them how to make and use a point file. We would have spent a great deal of time setting up the symbology and label parameters.  However, today within minutes all of the students created their capital city point file, defined parameters and were busy plotting capital cities. How cool is that!

Enjoy! I know I sure am!

Wednesday, April 20, 2011

Data - The Latest Edition of the WPI (World Port Index) from NGA Maritime Safety Information

One of the more popular data files offered from this site is the NGA Maritime Safety Information World Port Index. In 2006, I secured a copy of the WPI database in KML file format. For 2-years I made this abbreviated version of the WPI available to any wanting a copy.

In 2008, I secured a copy of the WPI in MS Access format. I reworked the data, getting an MS Excel spreadsheet which was ultimately converted into an ESRI shapefile which I made available to any wanting a copy.

I am not a regular visitor to NGA Maritime Safety Information, but today I chanced to visit it. In looking at the WPI and what was being offered, I was pleased to discover that they now offer the WPI in ESRI shapefile format.

So, here is the deal. If you want to download the WPI data directly from the NGA MSI unit follow this link. If you want to download the WPI shapefile and a pdf file of the WPI 150 book follow this link.

Enjoy!

Monday, January 17, 2011

Marmara Island TR - Modifying SRTM v4 TIF with EVS Precision Coastal Vector File

Turkey - SRTM Vector Modified

Turkey - SRTM with EVS Vector Modifications

The map of Turkey on the left is a portion of a 600-MB World Map created by Tom Patterson. His excellent and informative website, Shaded Relief, contains a wide variety of shaded relief maps. He explains how you could create your own shaded relief maps. I have been content to download his finished maps and use them in my classroom. The students love working with them.

I have been a long time user of SRTM data. Using tools within Global Mapper, I was able to generate interesting 3D views of islands. Last week I came across SRTM v4 data at CGIAR Consortium for Spatial Information (CGIAR-CSI), which I call Cigar (See-gar) for short. I downloaded a number of SRTM TIF images covering Turkey, where I am plotting Roman era towns and cities. Using the Shaded Relief Natural Earth 1 world map I was able to plot at scales of 1:1500000 to 1:1000000. When I attempted to work closer the map became a screen full of pixels. What to do?


Marmara Island - SRTM EVS Modifications Before and After (1-25,000)

Marmara Island - SRTM EVS Modifications Before and After (1:25,000)

The SRTM v4 data offered me some intriguing possibilities. First, I was able to zoom into areas at scales between 1:500,000 down to 1:50,000. At 1:50,000 I had to contend with pixels. The vertical side of a pixel in the part of the world I am working in is 90 meters, the horizontal side is 70 meters. Clunky looking when working at 1:50,000. It was then that I had my "ah-ha" moment. I loaded Landsat imagery on top of the SRTM imagery. I then digitized shorelines using the Landsat imagery (section 1). I switched off the Landsat imagery and my EVS precision shoreline cut through SRTM v4 pixels (section 2) and allowed me to determine the shoreline on the SRTM image. The SRTM modified shoreline is now useful to scales as fine as 1:25,000 (section 4).

I know! A 14.5 meter pixel defining a 90-meter pixels leads to potential problems. However, for my purposes, plotting Roman era towns and cities, these SRTMs modified with EVS precision shorelines work just fine.


Marmara Island Vicinity - SRTM with EVS Modifications Before and After (1-250,000)

Marmara Island Vicinity - SRTM with EVS Modifications Before and After (1-250,000)

And at 1:250,000, they look great!

A word about my custom hypsometric tints. The colors I initially took from the Shaded Relief website. But I have since tweaked them a number of times. The current version, certainly not my last, looks great for this part of the world.

I am slowly, but surely working my way around the shoreline of the Sea of Marmara, a place I spent time as a young man. I do hope this was both informative and interesting.

Enjoy!

Sunday, June 27, 2010

How To Digitize Vegetation and Land Layers using Landsat Imagery at 1:12,500 Scale

Faaite Atoll FP - Comparison - Landsat Image, EVS Precision Map, DigitalGlobe Image (1-12,500)

Faaite Atoll FP - Comparison - Landsat Image, EVS Precision Map, DigitalGlobe Image (1:12,500)

I keep telling all of you that I typically digitize off of Landsat imagery at approximately 1:12,500 scale. Checking out the above montage you will see a Landsat image of a portion of Faaite Atoll FP. Beneath it are two layers of information I digitized using Landsat as base imagery, vegetation and land. The final DigitalGlobe image from Google Earth is of the same stretch of atoll. The Landsat image has a green hue over all of the land and vegetation features. However, having digitized so many islands the sand or low vegetation, which I classify as land is identifiable. My Landsat derived vegetation layer is a decent approximation based on the vegetation shown on both Landsat and DigitalGlobe's hires imagery. The digitized land layer, I believe, is a strong match.

Why should one care at what scale one is able to digitize using Landsat as base imagery? Ask any photogrammetrist and they will tell you Landsat is reliable between 1:125,000 to 1:62,500. Each pixel covers a ground area of 14.5 meters by 14.5 meters. However, working at 1:12,500 does not render an image useless, but allows one to discern details in a rough but usable fashion. I can't make out individual trees, but I can identify stands of vegetation and most often the density of that vegetation. The most difficult feature on an atoll to reliably digitize is that portion of the reef which is awash depending on the time of day (high tide or low tide) and the amount of vegetation found growing on the reef. It is often difficult to determine whether the feature is above water land or below water shallow reef. Typically, if I'm uncertain I classify the feature as above water land.

Who knows, one day you might want to try your hand at island map making and you will want advise as to what scale you might expect to work at using Landsat as your base imagery. Digitizing at 1:12,500 should work just fine. Give it a try.

Saturday, June 26, 2010

Tepoto Nord FP - A Redo of a Redo of a Small Coral Island

Tepoto Island FP - Image

Tepoto Nord FP - Landsat Image from S-07-10_2000 (1:20,000)


Tepoto Island FP - ISS002-E-8862

Tepoto Nord FP - ISS002-E-8862 Image


Tepoto Island FP - Map

Tepoto Nord FP - EVS Precision Map (1:20,000)

My first map of Tepoto Nord was completed on March 31, 2006. I used Landsat as my base imagery. Most of my finish work was done using Marplot, a fine poor-man's GIS program. In December 2006 , I came upon the ISS image of Tepoto Nord. I decided to redo my original work using the ISS imagery to digitize from.

I look at my completed Tepoto Nord mapping project today and contemplate how far my map making skills have progressed. My digitizing of shorelines, vegetation and reefs remains fairly consistent. I routinely work at between 1:12,000 to 1:8,000, depending on my base imagery and the ultimate objective for my map. I am content to map four to five layers of information taking what Landsat is able to provide. The first time I mapped this island, I remember being frustrated by the Landsat imagery. The odd colors and blurred appearance of the island made digitizing problematic. Eventually, I came upon the ISS image and was able to redo my mapping of this small island in a more satisfactory manner. I reposted the map and base imagery in December 2006 and gave this small island no more thought.

That is until I received a question from an EVS Islands reader. He wanted to know everything he could about this small island. I answered that he should contact Alex W du Prel, publisher of Tahiti-Pacifique magazine. If anyone could give information about this small island, Alex is the man. After answering the reader's question, I checked out my map of the island. Unsatisfactory! The map presentation choices I make today are far superior to those I made in 2006. I decided to redo my redo of this small coral island.


Tepoto Island Nord FP - DigitalGlobe Image from Google Earth (1-12,000)

Tepoto Nord FP - DigitalGlobe Image from Google Earth (1:12,000)


Tepoto Island Nord FP - EEVS Precision Map (1-12,000)

Tepoto Nord FP - EEVS Precision Map (1:12,000)

I checked out Google Earth, as almost all of the islands within the Tuamotus are covered by DigitalGlobe's hires imagery. Sure enough, Tepoto Nord has excellent, cloud-free imagery from which I could redigitize various layers of information with a high degree of confidence. Seven layers of information later my redo of the redo is done. Since I have no designs to offer the map for commercial purposes, I decided to use DigitalGlobe imagery as my base imagery. I have worked on this redo of a redo for about two weeks. Not because it was particularly difficult, but I've been busy with school. Finally, I have a Saturday with no pressing projects. Only this, to finish my Tepoto Nord FP map. Pretty nice, huh?

Enjoy!

Monday, April 12, 2010

Reao Atoll FP - Finished . . . At Last!

Reao Atoll - Island Locator

Reao Atoll


Reao Atoll - ISS004 Image Mosaic (1-70,000)

Reao Atoll - ISS004 Image Mosaic (1:70,000)


Reao Atoll - EVS Precision Map (1-70,000)

Reao Atoll - EEVS Precision Map (1:70,000)

Reao or Natūpe is an atoll in the eastern expanses of the Tuamotu group in French Polynesia. The closest land is Pukarua Atoll, located 48 km to the WNW.

Reao is 24.5 km long and its maximum width is 5 km. The whole length of its north-eastern rim is occupied by a single long island. There is no navigable pass into the lagoon.

Reao Atoll's population is 344 inhabitants.

That is about it for Reao Atoll on the internet. There might be some scattered bits of information, but nothing of newsworthy significance. Why? It could be the location. Unlike many of the other atolls making up the Tuamotus that receive numerous pleasure cruisers, Reao Atoll is situated away from the normal cruising routes. In addition the lagoon has no entrance for sailing vessels making for percarious landings on and off of the main island.

Even with the geographical difficulties associated with Reao Atoll, I wouldn't mind visiting. The southern end of the atoll looks a bit on the wild side. If not real wild, it looks to be far from the population center of the island located on it's northern end. One could perhaps find an isolated small motu along the atoll's western edge. There are in the neighborhood of 50 motus along this edge of the atoll. I am certain one of these small motus could offer one a few days of solitude. If not a few days, for sure a few hours.

Now for a few comments on the map. First, the base imagery is from ISS004. I took 3 excellent images and assembled them into a mosaic of the entire island. I rotated the image about 37° to align it with the atoll's true alignment. I had created a shoreline of Reao Atoll a few years back, but had not saved the georectified image. All I had to work with was the island polygons which came from the ISS004 imagery. I used over 37 GCPs (ground control points) to georectify the ISS004 image mosaic. It wasn't until this weekend that I had both time and energy to complete my typical four vector layers - island polygons, vegetation polygons, shallow reef polygon and lagoon polygon. I completed all of the layers as Phil Mickelson was busy winning the Masters for the 3rd time.

P.S. - Later that day, I compiled my first OSM formatted vector file consisting of the island polygons. Ultimately my goal is to place my EVS copyright free vectors onto OpenStreetMap. That is another story for later time.

Wednesday, March 17, 2010

Marutea Atoll Nord FP - An Uninhabited Atoll...Kind Of

King George Islands FP - Locator Map Wagner IV World

Marutea Atoll Nord FP


Marutea Atoll Nord FP - Landsat ETM S-07-15_2000  Image (1-150,000)

Marutea Atoll Nord FP - Landsat ETM S-07-15_2000 Image (1:150,000)

A portion of the Landsat ETM+ image looks great, the other portion is cloud covered. If I had only used the Landsat image to create my EVS precision map, it would have been an incomplete effort. Fortunately, ISS imagery helped to fill in the gap.


Marutea Atoll Nord FP - ISS006E37438 Modified Image (1-150,000)

Marutea Atoll Nord FP - ISS006E37438 Image Modified (1:150,000)

First I had to rotate the ISS image and georectify it to my Landsat base image. I was able to do it after much tweaking of the ISS image it was positioned properly for my mapping purposes. Many of the coral heads, which I classify as shallow reef, were derived from the ISS image.

Marutea Atoll Nord FP - EVs Precision Map (1-150,000)

Marutea Atoll Nord FP - EVs Precision Map (1-150,000)

And here is the finished map! If one requires hi-res imagery, it can be found in Google Earth. Located at the channel leading into the lagoon are a few houses. I suspect they are used by coconut or black pearl harvesters. Although the island is uninhabited, people frequent the atoll doing the things that people do, harvesting resources.

Looking at the DigitalGlobe imagery found in Google Earth, large stretches of the island appear to be without a sand covering. It looks as if the island was washed over by a typhoon or a storm surge. Perhaps someone with first hand knowledge might share more about this uninhabited atoll...kind of.

Enjoy!

Sunday, February 28, 2010

Thoughts - Which Color Scheme Works Best for EVS Maps?

King George Islands FP - Locator Map Wagner IV World

King George Islands FP


King George Islands FP - Landsat ETM Image S-06-10 (1-175,000)

King George Islands FP - Landsat ETM S-06-10_2000 Image (1:175,000)


King George Islands FP - EVS Precision Map (1-175000)

King George Islands FP - EVS Precision Map (1:175000)


Takapoto Atoll FP - EVS Precision Map (1-80,000)

Takapoto Atoll FP - EVS Precision Map (1:80,000)

I spent today digitizing the King George Islands located in the Tuamotu Islands FP. The top atoll, Takapoto, was just completed using my new NIMA color scheme. Not only am I limiting layers to EVS island projects to island polygon, reef shallow, lagoon and island water feature, but I've changed my color scheme to match NIMA's nautical charts. My current color scheme is as follows:

island polygon is R-245 G-245 B245

reef shallow polygon is R-205 G-225 B-235

lagoon is R-225 G-250 B-255.


Takaroa Atoll FP - EVS Precision Map (1-80,000)

Takaroa Atoll FP - EVS Precision Map (1:80,000)

Takaroa Atoll, completed a few months ago, contains my old color scheme:

island polygon is R-240 G-232 B-217

reef awash is R-208 G-234 B-224

reef shallow is R-153 G-214 B-236

lagoon is R-090 G-169 B-211

In both projects the vegetation layer R-157 G-179 B-151 and the deep ocean layer R-165 G-207 B-231 are unchanged.

For visual appeal, I like the old style. The NIMA nautical chart style gives a cleaner, crisper look. What do you think?

Enjoy!

Tuesday, February 16, 2010

Nosy Antaly-Be, MA - Fishermen, Tourists and WWII Japanese Midget Submarines

Nosy Antaly-Be MA - Locator Map

Nosy Antaly-Be, MA,


Nosy Antaly-Be MA - DigitalGlobe Image from Google Earth (1-12500)

Nosy Antaly-Be, MA - DigitalGlobe Image from Google Earth (1:12,500)


Nosy Antaly Be MA - EEVS Precision Map (1-12500)

Nosy Antaly-Be, MA - EEVS Precision Map (1:12,500)

Every so often I like to scout a coastline in Google Earth to find an interesting island to map. Nosy Antaly-Be's image is cloud-free, hi-resolution and located along the eastern shore of the northern peninsula of Madagascar. The two islands I mapped are the northern most of a cluster of islands that are just off shore as one enters Diego-Suarez Bay. I mapped these two islands because I was bored with my current project, remapping Papua New Guinea, a very big job. I wanted to make a pretty map and to use DigitalGlobe imagery. So far, so good!

I mapped the islands quickly and completed all of the additional details using Global Mapper. My cursory check for information concerning these two islands initially turned up nothing of great interest. The semi-permanent population was made up of fishermen and tourists. Then came the WWII Japanese midget submarines. In 1942 Japan flush with a number of victories in Southeast Asia looked to control the entire Indian Ocean. A key area to control was the northern end of Madagascar. From this vantage point they would have been able to intercept allied shipping with ease. They attacked ships located in Diego-Suarez Bay in May, 1942. One ship was damaged and another was sunk with a lose of 6 crewmen. If you would like to know more about the "Whys" and "What Fors" follow this link, Imperial Submarines. The article will give you loads of background information concerning Japanese midget submarines and the war in Madagascar.

Life never fails to intrigue me. I select two nondescript islands and they turn out to be used to screen Japanese ships prior to an attack on ships in Diego-Suarez Bay. Who would have thunk it.

Enjoy!

Monday, February 15, 2010

Caspian Sea Isobaths from Russian Topographic Maps

Caspian Sea Contours - Map

Caspian Sea Isobaths - Taken from 1:1,000,000 Mapping


Caspian Sea Isobaths - Entire Sea (1-5,000,000)

Caspian Sea Isobaths - Entire Sea (1:5,000,000)

If I'm not careful, I can turn a finite mapping project into a never ending task, one that requires tweaks on top of tweaks. My Caspian Sea isobaths fall into that type of project. I have worked on the Caspian Sea shoreline and now isobaths since 2006 and I'm still not finished. The northern shore, including the Volga River delta remain my final shoreline to map. At my current rate I should be finished around 2012. In the mean time I would like to share my recently completed Caspian Sea isobaths. These isobaths were taken from Russian topographic maps downloaded from Poehali.org. One can download Russian topographic maps for free. The maps are georeferenced and load easily into most mapping programs. My Caspian Sea topographic map is a mosaic of 65 individual maps at scales between 1:500,000 to 1:100,000. All of these maps contain isobaths. Using the most detailed scale, I constructed the following isobaths: -10m, -20m, -50m, -100m, -150m, -200m, -300m, -400m, -500m, and -700m. Compared to the other Caspian Sea isobaths, mine differ. I hesitate to claim my isobaths are more accurate. I suspect they are, as they were derived from 1:500,000 to 1:100,000 scale maps. The other isobaths were taken from 1:1,000,000 scale maps.


Caspian Sea Isobaths - Baku Vicinity (1-250,000)

Caspian Sea Isobaths - Baku Vicinity (1:250,000)

Where my isobaths prove most interesting is when one zooms into an area. An interesting area to study these isobaths is around Baku, the site of many oil rigs. The isobaths twist and turn in and around oil rigs as one would expect.


Caspian Sea Isobaths - Baku Vicinity Offshore (1-62,500)

Caspian Sea Isobaths - Baku Vicinity Offshore (1:62,500))

Currently, my Caspian Sea isobaths are quietly residing on my hard drive. Before I do anything with them, other than my own mapping, I need to secure permission from Poehali.org. I know I did an excellent job tracing these unique isobaths. Not sure this is going to be a "give away". Would love to make a buck or two off of this data set. We'll see.

Enjoy!

Wednesday, December 30, 2009

Thoughts - North Sentinel Island Five Years After the "Big" One

nsentinelis_ast_2004337_lrg Cropped

North Sentinel Island - Pre December 26, 2004

North Sentinel Island is home to a few hundred of the most isolated people on the earth. This group of people has chosen to remain separate from all other peoples. To the credit of India, they have been allowed to remain separate. Prior to December 26, 2004, the inhabitants were content to hunt and gather on their small forest covered island. Then came the dreadful 9.0 earthquake that caused death and destruction throughout this part of the world. North Sentinel Island was not spared. It is unclear if any of the inhabitants were killed as a result of the earthquake. What is clear is that the island underwent a dramatic transformation. This small island was thrust upward. The submerged reef was no longer submerged.


nsentinelis_ast_2005051_lrg Cropped

North Sentinel Island - February 2005

The February 2005 image shows the once submerged reef exposed above water. The forest is intact, but the island's fringing reef is now permanently above water. The stark white indicates that the reef is a new comer to the above-water environment.


nsentinelisland_ali_2009324_lrg Cropped

North Sentinel Island - November 20, 2009

Fast forward to last month and one sees the reef still above water, but undergoing a gradual color change. As the once bone white reef remains in contact with the outside air, dust particles are blown onto the reef daily, algae colonies live and die and organic debris flows out from the island proper onto the reef, all of this contributing to the raised reef's gradual discoloration.


North Sentinel Island - EEVS Map (1-62,500)

North Sentinel Island - EEVS Precision Map (1:62,500)

My post-earthquake map still gives a good picture of this small uplifted island. I'm glad it remains isolated and it's inhabitants have yet to encounter the world of modern man.

Enjoy!

Friday, November 27, 2009

Thoughts - They Aren't as Good as EVS Precision and That's the Fact , Jack!

Olimarao Atoll - Locator Map

Olimarao Atoll Locator Map

You all remember my last post, Olimarao Atoll? I spent a few days prior to posting it doing research into available online mapping. I checked out the standard mapping packages for Olimarao Atoll vicinity maps. Check out my results below...


Olimarao Atoll - Vicinity Map from Google Maps

Olimarao Atoll - Vicinity Map from Google Maps - Some land polygons, no labels.


Olimarao Atoll - Vicinity Map from Yahoo Local Maps

Olimarao Atoll - Vicinity Map from Yahoo Local Maps - Nothing here.


Olimarao Atoll - Vicinity Map from Bing Maps

Olimarao Atoll - Vicinity Map from Bing Maps - And nothing here.


Olimarao Atoll - Vicinity Map from OpenStreetMap

Olimarao Atoll - Vicinity Map from OpenStreetMap - Land polygons and labels.

Google, Yahoo and Bing Maps rely on satellite imagery. The underlying maps of these oceanic island areas are largely neglected in map coverage. Google Maps provides land polygons from a mapping file similar to WVS 1:250,000. OpenStreetMap uses NGA PGS polygons along with NGA Country name files. Clearly the superior map product for oceanic islands is found on OpenStreetMap. But wait! What about a vicinity map using what I call EVS rough precision digitizing. Using Landsat ETM+ imagery, I could quickly digitize island polygons and reefs giving a much clearer map of the island.


Elato, Lomolior and Olimarao Atolls - Landsat N55-05_2000 Coverage

Elato, Lomolior and Olimarao Atolls - Landsat N55-05_2000 Coverage

Landsat N55-05_2000 is the imagery I initially tried to work with. As you can see, The vicinity is not covered. It is a blank. So I did what any good mapper would do, improvised. Using Google Earth, I found the blank area and DigitalGlobe had hi-res imagery of the islands located within the blank area.


Elato and Lomolior Atolls - DG Preview Image from GE

Elato and Lomolior Atolls - DG Preview Image from GE


Elato and Lomolior Atolls - DG Preview Image from GE Cropped

Elato and Lomolior Atolls - DG Preview Image from GE Cropped

I decided to use the DG Image Preview from GE. I copied it, cropped it and georectified it. From there, I was able to complete the digitizing within a few minutes. I did this for all islands within the Landsat blank area. Atolls should have reefs digitized as they make up a critically important aspect of this feature. My finished map uses five layers - 1) land polygon 2) reef shallow 3) reef deep 4) ocean and 5) name labels. My island name layer is an extract from NGA's country files.


Olimarao Atoll - Vicinity Map from EVS Rough Precision (1-500,000)

Olimarao Atoll - Vicinity Map from EVS Rough Precision (1-500,000)

This was all done using Global Mapper. The scale for the above map is 1:500,000. Now that is what I call a real oceanic island vicinity map.

Enjoy!

Wednesday, November 25, 2009

Olimarao Atoll FM - A Northern Pacific Island Jewel and Uninhabited Too

Olimarao Atoll - Locator Map


Olimarao Atoll - DG Island Image from GE (1-25,000)

Olimarao Atoll - DG Island Image from GE (=~1:25,000)


Olimarao Atoll - EEVS Precision Map (1-25,000)

Olimarao Atoll - EEVS Precision Map (1:25,000)

After almost five years of EVS precision island mapping projects, countless comments from the curious and, most often, complimentary guests and thousands of hours of work aimed at making this website better...

1) I have struck a deal with a corporate "sugar daddy" that will pay me to make EVS and EEVS precision island maps as I see fit.

or

2) My wife finally put her foot down and instructed me to "shut it down"! I told her to back off and she left me for a younger, computer illiterate man.

or

3) I'm still making island maps, with my wife's blessing, and am still without a corporate "sugar daddy".

Okay, I'm at Option 3) and enjoying it. However, sometimes our complicated lives cause us to wish for profound simplicity. A place where one can get away from the pressures of "big city" living and spend a day making a single decision, that being to make no decisions.

By far, my most popular posts over the past few months have been about the challenge of locating and living on uninhabited islands. It started with my post "Thoughts - An Uninhabited Island and What You'll Need to Inhabit it 'Robinson Crusoe' Style" and continued with my post "Thoughts - How Many Uninhabited Islands in the World?". These two posts alone have generated over 1,000 page views. As the world's economies continue to struggle and the economically downtrodden victims hunt for ways out, a Google search of "uninhabited islands" will lead the desperate to my aforementioned posts.

Olimarao Atoll could be their Eden. The atoll is small, but affords one fairly secure anchorage near the large motu. The large amount of vegetation suggests an adequate supply of water, most probably in the form of a fresh water lens. The small size of the island might lead one to "island claustrophobia", manifest by a longing for continental security. However, according to the occasional yachtsperson stopping for a short stay, the island is beautiful beyond imagination. Could Olimarao Atoll be your Eden? More to follow...

Enjoy!

Sunday, November 8, 2009

Thoughts - Strange Maps: An Atlas of Cartographic Curiosities

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Strange Maps: An Atlas of Cartographic Curiosities

When I first exchanged emails with Frank Jacobs, it was shortly after my "Titan's Unnamed Methane Sea" had hit the internet. The subject of the map hit a hot button that translated into 1,000s of visits to this web site. Frank introduced himself and asked if I had visited his blog, Strange Maps. I had and shared that I thought it was a "kick". He revealed that he, likewise, was a follower of my mapping efforts. He most especially liked my Titan map and wondered if he might use it in a book he was going to have published. He quickly added, that he had no money to pay for the use of the map, but would make sure I got a copy of his completed book. "Of course!" I said, "You are welcome to use my map. Just give me proper credit." Deal done!

Now let me tell you what I really thought. Oh, sure. This guy is going to publish a book about strange maps. I'll probably get a pdf copy or a link to his self-published effort. Unfortunately, I do have a healthy streak of skepticisim. After our exchanges I forgot about Frank and his book.


Silly me! I will never doubt Frank Jacobs again. True to his word, last week Fedex delivered a package from the UK. Inside was a slick copy of Strange Maps, Frank's book. I quickly leafed through it and there was my Titan map on pages 206-207. A nice writeup is included speculating on a name for this methane sea. And, sure enough, a paragraph about the author of the map, me.

Buy the book! Amazon.com lists it at $19.80. Support a fellow map lover!


Titan's Unnamed Methane Sea with Lat-Lon Grid (1-750,000)

Titan's Unnamed Methane Sea with Lat-Lon Grid (1-750,000)

And, once again, this is my map of Titan's Unnamed Methane Sea. It is still an interesting effort and now my first published map.

Enjoy!