Thoughts - My Evolving Map Product

Marutea Atoll - EVS Precision Map (1:125,000)

In February 2006, my mapping craft was beginning. I could digitize a shoreline with the best of them, but my color selections were evolving. Not only my color selection, but the entire layout of a finished map was evolving. I enjoy using Marplot to finish my maps. I know there are more flexible mapping packages that will allow one to finish maps as functional and appealing products. I know, but Marplot is my package of choice for the time being. When I really have to "pretty" a map, I work in ImageForge. It is a freeware draw and design package. I tried Gimp, but I am quite comfortable working with ImageForge.

That said, in February 2006, I completed all of my map finish work using Marplot. At the time, I liked my efforts, but saw room for improvement. For the past two plus years, that is what I have attempted to do, improve all aspects of my mapping work. I now digitize shorelines from Landsat ETM+ mosaics at scales between 1:25,000 to 1:12,500. I know that is pushing the limits of Landsat ETM+ and 14.5 meter resolution, but the final map is of a greater accuracy when my initial digitizing is done at the aforementioned scales.

I have continually evolved my island mapping color scheme. Now I use bolder colors, fewer soft pastels and less brilliant greens. I expect my color scheme to continue changing. The aim is to give the viewer colors that contribute to a positive map reading experience and that share information meaningfully.

My map layout is changing. I see this aspect of my work being the most dynamic. Depending on the map's end use, the layout will either be quite simple (for posting) or more stylistic, more "pretty" if the subject is of great interest, the map for an end-user or I have time.

Marutea Atoll - EVS Precison Map (1:85,000)

This is the current Marutea Atoll EVS precison map product. I like it.

Enjoy!

Comparison - DCW, VMAP0 Shorelines and GYM's Mapping Opportunity

Shoreline Map Comparison - Yahoo, Google, MS and EVS Precison

Shoreline Map Comparison - DCW and VMAP0

This post shows that Google Maps, Yahoo Maps and MS Live Search Maps use DCW/VMAP0 global shorelines for their mapping, at least in the area of Rabul. That is 1:1,000,000 scale global map coverage. James Fee, a well-respected GIS professional, commented, "When it comes to precision, I think the efforts for GYM (Google, Yahoo, Microsoft) should be on the navigation/geocoding/routing and not shorelines." First, one must agree with James' statement that GYM's maps are intended primarily for navigation/geocoding/routing. I believe that their customers, global in reach, would subject GYM's maps to many other GIS uses beyond navigation/geocoding/routing. I know that there is an agressive effort within the GIS community to provide a richer, more powerful set of tools, allowing any of us the opportunity to explore more complex spatial issues using Google Maps and Google Earth as platforms of choice. Ultimately, the end user, faced with a spatial problem requiring small scale maps would either have to make their own map, pay to have a map made, use a substandard map in place or not use a map at all.

In addition, James seems to suggest that 1:1,000,000 scale is satisfactory for GYMs primary efforts of navigation/geocoding/routing. I understand his reasoning, but I disagree. Before teaching, I did extensive geocoding of environmental risks. Locational precision was critically important. 1:1,000,000 was an unworkable geocoding scale. To follow the flight path of an enemy aircraft using 1:1,000,000 is doable. However, to locate enironmental risks at that large of a scale is asking for problems. A misplotted environmental risk could well result in a lawsuit. Business locations was another area I worked in and locational precision determined an exclusive market and was a contractual promise to the franchisee.

James goes on to say, "For me the shorelines are somewhat irrelevant to the routing provided. If I do need good shorelines, I'll probably just be using the aerial imagery in the first place." Again, his reasoning seems to make sense, but I disagree. First, shorelines are not somewhat irrelevant, they are a dynamic boundary between man and water. A raster image of a shoreline is practical for some applications, but a vector defined shoreline offer one a wide range of mapping possibilities. If I am GYM's map guru, I want my customers to have the greatest mapping precision possible. I don't want to impose precision limitations when there is no need. EVS precision shorelines, on a global scale, requires money to fund the mapping effort and time to complete the project. It will be money well spent. The resulting shorelines and other feature/land use layers will allow the "G", the "Y" or the "M" to be the number one mapping destination for all users and that could generate lots of ad dollars.

Finally, vector maps allow for infinite zooming with no lose of detail. If the initial vectors are created from quality base imagery (i.e., Landsat ETM+) and the map customers are able to easily access these detailed vector maps, they can tackle complex spatial issues using GYM's hi-precision mapping. Thus a marketing boon to the company savy enough to provide the product.

Enjoy!

P.S. - After yesterday's post, I received a query from an individual about EVS precision mapping for a section of Canadian shoreline. He had used WVS/GHHS vectors and they were unsatisfactory for his project. I sent him NGA PGS vectors covering his target area. They looked okay at 1:250,000 scale. He loaded them and acknowledged they were a significant improvement over the WVS/GHHS vectors, but were angular and did not track a cloud-free shoreline as one would expect. I created EVS precision vectors for him. He compared them to NGA PGS vectors and immediately acknowledged their higher quality. He asked if I would go ahead and create EVS precision vectors for his entire study area. I will, but wouldn't it have been cool for him to go to one of the big three mapping portals and find this mapping not only available, but downloadable? I think so.

Comparison - Google Maps, Yahoo Maps, MS Live Search Maps and EVS Precision Maps

Shoreline Map Comparison - Yahoo, Google, MS and EVS Precison

Whose shoreline maps are currently the most accurate? Is it Google Maps? They have loads of bucks and a keen desire to put the best product into their sites. They must have the most accurate shorelines. Right? Nope, not them. Yahoo! Maps, the current darling of the stock market and Google "wannabe", has the same clunky shoreline used by Google. MS Live Search Maps has the prettiest maps. Lots of shaded hills and valleys, but clunky shorelines. For sure, MicroSoft must have the most accurate shorelines. For sure, not.

Would you believe, EVS Precision Maps has the most accurate shorelines compared to the big three map moguls. EVS precision mapping is derived from Landsat ETM+. Typically, it provides accurate shoreline depiction at scales between 1:100,000 to 1:50,000.

Rabul - MS Live Search Map

All map maker struggle with PPL (populated place) placement. The PPL data is available through NGA. I'm reasonably certain most of their data and locational information was derived from ONC (1:1,000,000) charts. Looking at the PPLs on the MS Live Search Map of the Rabul area, we see towns lined up in a grid. In the real world, this only happens in the midwest, not on New Britain Island in Papua New Guinea. One should replot these PPLs using Landsat ETM+ or hi-res imagery. The only thing certain about the above plots, is their locational uncertainty. But, back to shorelines.

Rabul - EVS Precision Maps

EVS Precision Maps provide the most accurate shoreline maps of the four being compared. The big three use, what appears to be DCW's 1:1,000,000 shorelines. 1:1,000,000 has it's uses, but when one zooms to 1:63,500 (1" to 1-mi), a shoreline that approximates reality is expected. EVS Precision Maps show that expected shoreline. Google Maps, MS Live Search Maps and Yahoo Maps do not.

Enjoy!

P.S. - I am aware of NGA PGS vector files, 24 tiles covering much of the world. They were derived from Landsat ETM+. EVS Precision Maps and NGA PGS should parallel each other. They do not. NGA PGS vectors used a digitizing algorithm to automate their work. Peculiar stutters, uncalled for strings of vectors and angular shorelines are often the norm. Also, NGA requested that water inundated areas (swamps, marshes, tidal flats) be excluded. This caused a great many problems in shoreline mapping. Also, the slightest cloud cover often thwarted their automated digitizing efforts. EVS Precision Maps consistently improve upon NGA PGS.

Reao Atoll FP - The Finished Map

Reao Atoll - ISS004-E-12987, 12988, 12989 Images (1:100,000)

Reao Atoll - Other Precision Map - Source ISS004 Images (1:100,000)

This is my finished shoreline map of Reao Atoll FP. The imagery covering this atoll is of sufficient detail that other layers of information can be digitized, if I wish. For now I just want to complete shorelines within the Tuamotus at EVS precision or better.

Enjoy!

How To Map Motus

View Larger Map

Zoom In to See Pukaruha and Reao Atolls

Reao Atoll FP - ISS004-E-12987, 12988, 12989 Images Modified (1:75,000)

For whatever reason Landsat ETM+ does not have a mosaic that covers Reao Atoll. Google Earth has Landsat imagery, but no imagery for this area at the NASA site where I download my Landsat ETM+'s. As I am making all of my maps without using DigitalGlobe imagery, because one day I might want to sell my shorelines, I must locate other imagery sources. The International Space Station (ISS) is a source of sometimes excellent imagery. And, in fact, ISS004 has 3 cloud-free, highly detailed images covering Reao Atoll, my current target project.

I downloaded, modified their sizes, constructed a "whole atoll" mosaic, rotated the image to align it with my base island shoreline vectors (NGA PGS vectors) and georectified this image using 7 GCPs.

Reao Atoll FP - Other Precision Mapping on ISS Images - Finished Motus (1:40,000)

Reao Atoll FP - Other Precision Mapping - Finished Motus (1:40,000)

Once I had a georectified image, my digitizing could proceed. I decided to map motus first, thus the title of this post. Motu mapping is quick, repetitive and gives one a sense of completion. Each motu is actually a small island. Reao Atoll will ultimately be made up of a 100 or more islands. The two above images show the results of about 2-hours worth of digitizing. I always strive for EVS precision, Landsat ETM+ resolution or better. This imagery allows me to exceed EVS precision. For mapping quality purposes, I label it as Other precision and label it's Source attribute as ISS-Hi Res. I have completed 58 Other precision island polygons. Let's look at the challenges one encounters as they map motus.

Reao Atoll FP - Other Precision - Digitizing Motu (1:10,000)

First, I am working at 1:10,000 scale. At this scale, I am able to maintain sharp feature clarity. In addition, this resolution allows me to make consistent shoreline determinations that will work with the scale of my finished map, between 1:50,000 to 1:25,000. My mapped shorelines consist of actual or suspected (based on color) above-water features. Sounds easy enough to consistently identify, but it isn't. After mapping a few thousand motus, I have learned to make a color(s) to shoreline decision and rigourously adhere to that definition. In imagery, color is god.

In the Reao Atoll image, the motu shorelines are identified as a white sand color. Having studied enough hi-res 1-meter imagery of reefs and motus, I know that between motus are features called hoas. These serve as channels allowing water to flow in and out of the lagoon. Eventually, these hoas fill up with coral rubble and sand, vegetation takes root and motus join motus to form a continuous land ring around a lagoon. Given enough time, the lagoon quite often fills in and, sea level cooperating, a flat island forms where an atoll once stood. Using my white sand color as my motu shoreline, I began digitizing.

Reao Atoll FP - Other Precision Mapping - Finished Motu (1:10,000)

If I do a good job, my project consists of a series of motu shorelines. The digitizing is monotonous, eye-straining and lately, my feet hurt because my chair is uncomfortable. But the finished map is what I work for. I'll share it with you when I've finished. Until then...

Enjoy!

Yadua Taba Island FJ - Home of the Fijian Crested Iguana Project

Yadua Taba Island - Landsat S-60-15_2000 (1:12,500)

Yadua Taba Island - EVS Precision Map (1:12,500)

As I was mapping this island, I kept repeating the Fred Flintstone saying "Yaba Daba Do". That was what Yadua Taba did to me. Now what it does for iguanas is something else. Yadua Taba is home sweet home to the few remaining Fijian Crested Iguanas. It is the hope of the Fijian Crested Iguana Project to enable the few remaining iguanas to survive. Not just survive, but perhaps to thrive.

Fijian Crested Iguana (from Reuters)

"A Fijian Crested Iguana sits on the head of a statue of a Komodo Dragon at Taronga Zoo in Sydney during an announcement of a funding boost for their conservation June 19, 2008. Only a few wild populations remain of the endangered iguana which is found on a several Fijian islands. The species faces possible extinction due to habitat destruction and competition from introduced species."

Enjoy!

How To Digitize Cloud-Obscured Shorelines

Raivava'e Atoll - EVS Precision Map on Landsat S-06-20_2000 (1-55,000)

As most of my regular readers know, the bulk of my mapping work is derived from Landsat ETM+. My primary reason for using Landsat ETM+ as base imagery is consistency of product. Typically, anywhere on earth this imagery is freely available, virtually cloud-free and consistently resolved to 14.5-meters per pixel. Great for my worldwide island mapping work. Plus, there are minimal copyright issues when using this imagery. All that is asked is that you credit the source imagery. Did I say "virtually cloud-free"? That is everywhere but in humid climates, in other words in and around islands. Oh, well, it is merely a challenge that the accomplished mapper learns to work around.

The above image is an example of cloud-obscured island imagery. Most of Raivava'e Atoll is visible, but those areas not visible are significant. How does one resolve these areas using copyright-free data (credit source data)? If I am unable to secure Landsat 1990 imagery, which quite often enables one to resolve cloud-obscured areas, I go to Shuttle photography. Specifically, searching for ISS (International Space Station) imagery.

Raivava'e Atoll - EVS Precision Map on ISD_ISS001-375-13 Modified (1-55,000)

Raivava'e Atoll has two images that show the atoll with virtually no clouds. These images are sufficiently large enough that one is able to zoom into and digitize features. First, however, the ISS image must be georectified. Global Mapper allows me to georectify ISS imagery using my Landsat base imagery. In georectifying this ISS image, I used 7 GCP's to ensure the ISS image lay precisely on top of the Landsat base image.

Raivava'e Atoll Outlying Motus - EVS Precision Map on Landsat S-06-20_2000 (1-10,000)

Raivava'e Atoll Outlying Motus - EVS Precision Map on ISD_ISS001-375-13 Modified (1-10,000)

Beginning with the cloud-obscured Landsat image above, I digitized as much of the atoll as possible. The cloud-obscured portions were identified and designated for further work. Visiting Shuttle photography, I found 2 cloud-free images of Raivava'e Atoll. I selected ISD_ISS001-375-13 as the better of the two images. I rotated it and cropped to the atoll. Using this modified ISS image, I was able to complete digitizing the cloud-obscured shoreline. When all else fails, I use WVS shorelines. They are crude compared to EVS precision, but they work.

I use red shorelines to designate EVS precision derived from Landsat base imagery. The green shorelines are designated as Other precision. The source for all Other precision shorelines in my Raivava'e Atoll map is the ISS imagery.

My EVS precision island map of Raivava'e Atoll is complete and I was able to digitize all shorelines in spite of clouds. Pretty cool, huh?

Enjoy!

Espiritu Santo NH - EVS Precision Details

Espiritu Santo NH - EVS Precision Map

A simple slideshow is all you get with this post. A simple slideshow of a detailed map of Espiritu Santo island. What I intended to demonstrate with this post is how detailed a shoreline one can create at EVS precision. Mapping created from 1-meter resolution imagery is far superior to Landsat ETM+. However, nothing in the public sector rivals EVS precision. Not WVS, Not NGA PGS, Not DCW. No non-commercial shoreline mapping rivals it. Not many commercial shorelines mapping rival it either. The nice thing about mapping at EVS precision, once it is finished there is no reason to redo. It is finished. And tonight, so am I.

Enjoy!

North Sentinel Island IN - Still The Most Isolated People

North Sentinel Island - Landsat ETM+ Image Circa 2000 From Google Earth (1:62,500)

North Sentinel Island - ESA Image 2005 (1-62,500)

Let's begin this post with a discussion of my two base images. The first one is a modified Landsat ETM+ extracted from Google Earth. I have the Landsat ETM+ image found on N-46-10_2000 and used it for one of the vegetation layers found on my completed map. However the shoreline, sand beach and forest was extracted from the Google Earth image. Both of the above images were georectified to my N-46-10_2000 image. The Landsat image is circa 2000. The ESA image was taken following the devastating December 2004 earthquake and tsunami. The offshore reefs underwater in the circa 2000 image are uplifted. They were raised as a direct result of the 9.0 earthquake. The island was also hit by a series of tsunamis which created death and destruction throughout the region.

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

My map displays both shorelines of North Sentinel Island. The enlarged beaches and submerged reefs are parts of the new shoreline. The island proper was mapped at scales between 1:12,500 to 1:6,250. The new shoreline and raised reefs were mapped at a scale of 1:50,000. The map is a nice effort. It looks good and reflects the effects of the December 2004 earthquake.

Sentineli Man ShootIng Arrow at Helicopter

I want to say a few things about a group of people that call North Sentinel Island home. They have called it home for about 60,000 years. They are a remnant of the original "out-of-Africa" movement around 100,000 years ago. Follow this link to the Andaman Association and their fascinating site about the Lonely Islands (Andaman Islands). George Weber has gathered information about the inhabitants of the Andamans and specifically the people inhabiting North Sentinel. This group wants nothing to do with the outside world. The population estimate is about 250 individuals. The picture, taken from the Andaman Association website shows the Sentineli's defiant attitude. After the December 2004 earthquake and tsunamis, the Indian government sent a group of concerned scientists to North Sentinel to check on the well-being of the inhabitants. The heli was greeted by the lone man attempting to shoot the big bothersome machine out of the sky. The Sentinelese are doing just fine and they could care less about the world and all of its mysteries. In fact the few crude attempts at contact are clumsy, at best, and insulting most often. I hope they are able to survive, if only to remind us of that different way in which we all once worked with nature and which is so different from our attempts to mold and control nature today.

Enjoy!

Thoughts - Mapping New Britain PP

I was explaining my mapping work to a person I met at a party earlier today. This individual asked all of the right questions ( What do you do? Where do you get your images? How do you digitize the shorelines? What do you do with your finished maps?) Poor guy! I answered every question with a detailed, lengthy and somewhat technically boring response. After my fifth lengthy reply, he excused himself and joined another group.

As I reflect on my exchange with this curious person, I am amazed at the breadth of my knowledge and convinced that I can be very boring. I really do know quite abit about digitizing shorelines. After a few thousand kilometers of continental shorelines and 9,000 island shorelines, I am able to digitize a precise shoreline (within the limitations of Landsat ETM+'s 14.5-meter resolution).

Early on, I had professional cartographers tell me my maps would be useful at 1:125,000 to 1:63,500. I have learned that my island shoreline maps are useful at scales well-below these upper limits. I typically post completed maps at 1:25,000 scale. After adding layers of information, they work well for an individual attempting to determine a relatively coarse view of an island. Landsat is not DigitalGlobe's hi-res imagery, but it does a great job at giving one a highly resolved broad view of a geographical area.

New Britain PP - Digitizing from Landsat S-55-05_2000 (1:19960)

So, how is it that I do what I do? In digitizing, that is. The above image shows a typical stretch of large island shoreline. An attempt to generate vector shorelines from Landsat ETM+ was done a few years ago. This data, called NGA PGS, is fairly good at defining a shoreline, but coastal swamps are excluded causing some very strange looking maps of islands. If the island or shoreline contains water-innundated shoreline, NGA PGS does not map it. They could have, but someone, somewhere thought it would be good to exclude it. My shorelines include these water-innundated areas. The red line in the above image is my completed EVS precision shoreline. Except for the final vector which I purposely placed in the sea, the shoreline is much more accurately delineated than NGA PGS, WVS, DCW or any of the other available global shorelines. I am not saying EVS precision shorelines are global yet. I am an optimist. Someone, somewhere, sooner than later will fund my mapping efforts and the result will be a global shoreline at EVS precision.

Enjoy!

Thoughts - FLASH! 8,000 Pacific Islands Mapped at EVS Precision

EPIP - Pacific Islands Overview

The 8,000 islands located in the following island groups: Papua New Guinea, Solomon Islands, Vanuatu, Fiji, Cook Islands, Western Samoa, Tonga and portions of Kiribati were mapped at EVS precision. Using Landsat ETM+ ortorectified image mosaics, which typically resolve to 14.5 meters per pixel as base imagery, Mr Minton spent in excess of 240-hours over 31-days digitizing, correcting and finalizing island shorelines throughout this region of the Pacific. Mr Minton used a variety of strategies to resolve cloud-obscured shorelines. Those that ultimately could not be resolved were mapped using World Vector shorelines. This impressive effort is being fine tuned using 1990 Landsat imagery, when available.

You heard it right! I spent the last month mapping thousands of islands at EVS precision. I did get paid to do it. Part of me wants to rest, as I sure deserve it. However, the island mapper in me demands that I resolve problem areas, primarily cloud-obscured areas, by correcting island shorelines using cloud-free imagery.

If you are interested in these shorelines, email me and let's talk.

Finally, I will finish mapping the balance of the Pacific islands at EVS precision. Stay tuned for updates on this effort.

Enjoy!