Surveying, Mapping and GIS

For the last few days I have been working on efforts to help Haiti earthquake response - part of this is mapping Haiti via OpenStreetMap. Currently, useful maps of Haiti are few and far between, in some case there are detailed maps for parts of the country and cities like Jacmel, but which are print maps (no digital edition exists), in many cases many decades old and outdated, in other instances the only maps which exist are small-scale, with limited detail. Commercial map platforms like Bing Maps, Google Maps and Yahoo vary greatly in their detail as well, and update cycles are slow - however, here, OpenStreetMap has been able to rapidly respond and provide very speedy and robust updates, to include capturing data about collapsed buildings, and so on.

Mikel Maron captures the speed and effectiveness of OpenStreetMap with these two screenshots of Port-Au-Prince, just before the earthquake and just after:

before:


after:


I would encourage any others who have time to contribute to get involved in this effort as well - editing can be done directly in OpenStreetMap via the 'edit' tab, which opens a web-based tool called Potlatch - or, a number of other tools are available as well. (You will need to register an account in order to edit - feel free to connect with me there as well - http://www.openstreetmap.org/user/Dave%20Smith). The OpenStreetMap WikiProject Haiti page provides a lot of good information and frequent updates. A number of data sources have been assembled, together with fresh post-earthquake imagery generously donated by companies like DigitalGlobe.

For folks who are interested in more robust tools, I primarily use Merkaartor which runs best on Windows platforms - others favor JOSM which is Java-based and runs on any platform supporting Java.

With either of these, you should be able to use the download function to navigate to an area of Haiti (select a relatively small area) and then download the OSM data

Some have wrestled with getting the various available imagery and map services to work properly in JOSM and Merkaartor - they are both a bit clunky about accessing WMS servers - I can offer some of my tips gleaned from a little debugging using Fiddler2: For Merkaartor, use Tools -> WMS Servers Editor and create a new entry with the following URL: http://maps.geography.uc.edu/cgi-bin/mapserv?map=/home/cgn/public_html/maps/mapfiles/haiti.map&version=1.1.0&SERVICE=WMS&REQUEST=GetMap? and show capabilities to access the DigitalGlobe CrisisEvent imagery (DG_crisis_event_service), select EPSG:4326 (only option available) and image/png and you should be able to go from there. If there is no image layer showing, go to Layers -> Add new image layer, and then right-click on the newly added image layer and select your newly-added WMS server for DigitalGlobe.

Digitization tasks are fairly intuitive - tools allow you to draw points, lines and polygons, as well as to create relations which allow multiple entities to be grouped together - however the absolute key to success is in proper use of tags to provide attribute values for any entities being created. These are generally intuitive as well, e.g. tag of highway, value of residential to turn a generic line into a residential road. It also helps to look at tagging of existing features, and to familiarize yourself with the features list - the OpenStreetMap wiki is searchable and quite useful. Finally, as terms of using the DigitalGlobe imagery, any data entered using their imagery should also be tagged with source=digitalglobe.

One of the other projects I have been working on is development of a set of tags that would be useful for emergency responders, relief and aid efforts - for this, I have started a wiki page http://wiki.openstreetmap.org/index.php?title=Humanitarian_OSM_Tags- any comments and thoughts can be added to the wiki page.

I am looking forward to attending the EPA GIS Workgroup meeting coming up in Boston. This time around, the spring meeting will be in Boston, at the Omni Parker House Hotel, May 15th to 18th.

It will be good to refresh some contacts and make some new ones. We are hoping to make some further inroads in the EPA GIS community, combining our present USEPA geospatial expertise and SDVOSB status to reach out and support USEPA regions and other USEPA program offices. For me, it's also another opportunity to go and visit with my relatives in Massachusetts.

In examining Rwanda and Cameroon, I came across a number of articles discussing limnic eruptions - this is a natural event, where large amounts of dissolved and trapped gases in lakes suddenly and catastrophically become released, causing death to all living things within a substantial radius of the lake.

Typically this is due to volcanic vents, which release CO₂, which becomes trapped in stratified layers deep in the lake. The trapped gases may remain undisturbed and in solution for long periods of time, and may continue to accumulate until an external event triggers instability, such as earthquake, landslide, rapid thermal change, or the like.

One particularly catastrophic and more well-known instance of this phenomenon is Lake Nyos, in Cameroon, where in August of 1986, an estimated 1,800 people and large amounts of livestock died due to suffocation. It is estimated that 1.6 million metric tons of CO₂ were released in that instance. As CO₂ is heavier than air, the gas fills valleys, and finds its way to low-lying areas in great concentration.

Fortunately this is a relatively uncommon occurrence - few lakes are known to have this type of supersaturation of gases and potential for catastrophic overturn. Lake Nyos is a fairly small lake, of 1.2 km² - Lake Monoun is another small lake in Cameroon which has had similar catastropic incidents and loss of life in the past.

Another lake that is somewhat disconcerting is Lake Kivu, bordering Rwanda and the Democratic Republic of Congo - Lake Kivu is much larger - 2,700 km², with a much larger population along its shores than these other lakes. It is unknown if Kivu is susceptible to similar massive overturn events, and Kivu has considerably greater depth that the two Cameroonian lakes, however it similarly displays the unusual supersaturation of gases characteristic of the other two lakes - and situated over the Rift Zone, and in proximity to Mount Nyiragongo, which last erupted in 2002- it is entirely possible that the same circumstances exist for continued contribution of CO₂ and other gases.

In some instances, the lakes are being degassed, via pipes which seek to gradually release the concentrated gases, similar to slowly letting the fizz out of a soda can.
One such project is being conducted by the Lake Nyos and Monoun Degassing Project.

In the Amazon Mechanical Turk effort to analyze imagery for potential clues in the disappearance of Jim Gray, I thus far managed to log 185 units of 5 images each, the count was well over 4000 when I started, and the last one I completed said 1 remaining. It was plainly evident that I had a great deal of company throughout this effort.

Certainly there were several instances of images where boats, along with their associated wakes, could be seen in the images, however a great many were difficult to read, with a great deal of reflectance, cloud cover, and so on.

It will be interesting to see what the next steps are - whether more data or additional passes will be offered up through Mechanical Turk, and if any of what participants identified will ultimately be able to correlated to other activity in the vicinity, or indeed provide clues to Gray's location.

UPDATE: Some additional images from a NASA aircraft have been posted to Mechanical Turk - see the following link: http://www.mturk.com/mturk/preview?groupId=J0XZ58STDWJZ5QY4F9M0

I have also located a blog site operated by the folks who have been organizing this effort: http://openphi.net/tenacious/
- They have posted quite a few updates and insights into the nature of the imagery and ongoing effort

Having a five-year-old in the house, I usually snag any little conference goodies, such as the LizardTech lizards, yo-yos, and other things of interest... And ESRI never fails to please with a few goodies of their own at the User Conferences.

One interesting one is the Mapping for Congress book, published by ESRI press, it was distributed in the conference bags at sign-in. In usual case-study style, they present a gallery of interesting maps that were developed in response to various Congressional inquiries and toward exhibits and policy development by the Library of Congress Congressional Cartography Program. Plenty of great studies toward support of public policy, social justice and other areas to be found in this book.

Another one that I grabbed at the conference was GIS for Homeland Security, which in a vest-pocket size, provides a good high-level overview of various initiatives, Homeland Security Presidential Directives, and other ongoing efforts toward preparedness and response. A great feature of this book is the extensive glossary, which provides over 30 pages of definitions and explanations of the various terms, definitions and TLAs (three-letter acronyms) that one encounters in the Homeland Security arena.

What appears to be a real gem that was handed out in the conference bags is Standards for Success: GIS for Federal Progress and Accountability which as a sort of follow-on to Measuring Up: The Business Case for GIS - it is of particular interest to me, as it presents many federal geospatial projects - and here, the business case needs to begin getting aligned with the OMB GeoLoB, Agency Blueprints, FEA, CPIC and other directions. This book doesn't appear to touch on these directly, but does provide a high-level overview that is spot on, when it comes to streamlining business, collaboration, business logic and decision support, and optimal use of resources.

Going to have to read that one in a bit more detail.