Surveying, Mapping and GIS

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.

I got a mailing today, probably several others of you did as well - announcing the Trimble VX Spatial Station. I had to chuckle, looking at the Matrix theme they put together for the ad campaign, considering the target as the typical pragmatic, grizzled, muddy-boots, over-50 demographic of surveyors... "wake up, Neo..."



I shouldn't tease Trimble - it is probably a lot more reflective of their own young and forward-looking demographic within Trimble, given their leadership and innovation in many other areas recently. Looks like a great product, and the next natural sequence of evolution as the Robotic/Reflectorless Total Station fuses with the 3D Scanner. It's the sort of thing that gets people like me thinking, what is the next phase of evolution.

For example, I was interested to see such things as fellow SDVOSB Penobscot Bay mounting scanners on robots, as well as another firm that we've worked with in the past, Spatial Integrated Systems / SIS, who has stripped-down scanners for confined spaces, such as on submarines.

So what's next in the far, or maybe not-so-far future? Perhaps a fusion of GPS and other technologies as well - a device you can carry in your pocket, which, when whipped out, establishes its geodetic position to centimeter level, scans the environment, and instantly constructs a georeferenced, 3-D spatial and temporal virtual environment, and stitches it in with other models already captured for a seamless database. Perhaps hyperspectral sensors, spectroscopy to determine the materials of the environment and more...

Imagine the design tools - you capture the environment, then don a headset which lets you mold and sculpt the environment in 3-D almost like it was wet clay. As you modify things, a number of models run simultaneously - finite elements analysis examining the structural details, other routines running to examine other impacts - stormwater and erosion, traffic, you name it.

Hey, a guy can dream, can't he?

The MAPPS lawsuit, to clarify provisions of the Brooks act, as they pertain to geospatial, mapping and surveying activities has been postponed from this Friday to 2/9, per Adena Shutzberg at Directions Magazine - it will be interesting to see how this all pans out.

I am looking forward to spending some time over the next few days at the Pennsylvania Surveyors' Conference. It's always a great time to catch up with old friends, as well as get some updates on various things going on in the world of surveying and mapping. This year I am going to focus on the GPS track, something I have not been doing my due dilligence on of late.

On another note, it's beginning to amaze me how many geospatial-related conferences are cropping up of late. I just got a notice of the Rocket City conference in Huntsville, and there have been several others in the last few months and more upcoming. I can certainly understand thematic conferences, regional ones, vendor-
oriented ones... but are we getting to the point where there are just too many?

A battle is imminent, with several professional societies challenging the Federal Government on whether the Brooks Act should apply to geospatial contracting efforts.

A trial is scheduled for February 2nd, Private Photogrammetric Surveyors (MAPPS), American Society of Civil Engineers (ASCE), National Society of Professional Engineers (NSPE) and Council on Federal Procurement of Architectural and Engineering Services (COFPAES) v. United States of America - to provide definition and clarity and to look toward Qualifications-Based Selection (QBS) in mapping procurements.

Directions Magazine provides their perspective on the issue, and drew my attention. MAPPS provides a page discussing the background and legal history.

The outcome should prove interesting - many issues have been simmering with regard to state and federal definitions of surveying and mapping, particularly as technologies have continued to evolve. I have my own unique perspective, as a geospatial practitioner, as a licensed professional, and as a member of a state licensing board - and these perspectives are in some ways in great harmony, largely in support of Qualifications-based Selection, however also in some ways in dissonance with QBS, as mere fact of licensure may not qualify one to perform the work. As a regulatory body, the State Registration Boards' duty is to ensure protection of the public - and in many ways, lack of adherence to the Brooks Act has skirted this. However, many state laws are similarly overbroad, and/or antiquated.

I have previously voiced my skepticism of Galileo's business model as a European GPS provider, as well as reported on many other public critiques which were unfavorable- Now it turns out that the Galileo paid subscriber business model has shown it can be compromised. According to Science Daily, a team at Cornell, when frustrated with the lack of cooperation, were able to monitor Giove-A signals, and able to perform signal processing to reverse-engineer the algorithm used to generate the Pseudo-Random Numbers (PRNs) essential for processing the transmission.

The Pennsylvania Society of Land Surveyors scored a victory today, with the passage of House Bill 496. This bill imposes penalties for the destruction of survey monuments, and it also reduces a surveyor's liability for errors from 21 years to 12 years.

Destruction of monuments has been a longstanding problem, from construction obliterating monuments and not properly replacing them, to property owners' disputes, and other causes. With monuments destroyed, removed, or otherwise obliterated, it makes retracement and documentation of subsequent surveys more difficult, and removes some of the certainty from the location of the corners.

Additionally, it has long been argued that the 21-year liability limitation has been unrealistic, particularly given that licensed Engineers enjoyed a much shorter liability limitation, with much greater risk of harm to life.

The text of the bill:

GIS Development magazine discusses an item on Portal Iraq - establishment of a digital registration system for land ownership in Iraq. As numerous records had been destroyed during the war, it had been crucial to re-establish commercial agricultural operations- The Iraq Ministry of Agriculture had established a framework, however they did not have adequate resources for making the system functional. According to the article, the USAID Agriculture Reconstruction and Development for Iraq gave the Ministry of Agriculture hardware, software and "digital mapping equipment, satellite imagery".

It sounds like the system goes beyond mere recordkeeping. Is it possible that this may be an opportunity for establishment of a digital, coordinated cadastre for Iraq? Between the 6 NGS CORS stations that have recently been set up in Iraq by the 175th Engineer Bn. along with the 2-300 station HARN network recently reported in American Surveyor magazine, they are well set for moving into a modern era.