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Mikel Maron :: Building Digital Technology for Our Planet

JRC Tsunami Propogation Model

The JRC has developed a Tsunami modelling web service, which (I’m very proud to say) makes use of worldKit for animating tsunami model results and referencing stored requests.

A model for Tsunami propagation has been developed by JRC. The model allows to predict the propagation wave once the initial location of the earthquake is fixed. The model, in contrast to other detailed 3d models, is extremely fast but sufficiently precise that can be integrated in the Global Disaster Alert System to give a first estimate should the conditions favour a Tsunami

Here is a sample animation of a simulated tsunami using worldKit. The RSS backing the simulation uses the new <geo:polygon> tag, a list of lat/long/alt triples supported in beta for worldKit.

Incredibly, this online simulation service, plus earthquake rss feeds, could provide the core resources for a tsunami warning system today. Monitor the quake RSS for magnitude 7 or greater events. New tsunami simulations can be run simply by GET request. Pass in the lat/lon from the quake RSS, and an email address to receive the results. In about 20 seconds, an email is sent with a link to the results. Parse that email to get the link, and from it determine the link of the simulation’s RSS feed. Download that feed, and you have the coordinates for the area of possible impact for the next 9 hours.

Provide a service for people to register their location. If that location resides within a tsunami warning area, send an email or text. Not sure if I’d depend on a web hacker level service for an emergency response system, but it is a compelling idea to bypass complex web service orchestrations and mapping protocols, especially when there is still no official system in place.

The JRC is working on integrating this simulation into a robust warning system, including gov’t and response agencies. And further confirmation of the model.

One major issue for a tsunami hackers alert service, discussed in their system analysis is that the tsunami epicenter and earthquake epicenter can be widely different; the Indian Ocean tsunami was centered on the midpoint of the fault on which the earthquake took place.

VMap0

VMap0 is an incredible set of geospatial data. Unclassified and published by the US Military National Geospatial-Intelligence Agency, the same agency that publishes the GEONet Names Server (which backs the worldKit geocoder).

The breadth and depth of the data is, well, I’ll just paste what mapability has to say…

In a world of secrets and closed access to data, it comes as a pleasant surprise to discover that there is a huge quantity of data available to anyone, free of charge. This data has complete word coverage, and an astonishing range of data types all gathered together in one package. Need the national coastlines, elevation contours, roads and railways for any country you can think of ? They are there, of course. Populated places, administrative boundaries, inland waterways ? There too. But how about the more obscure data types - Lighthouse, Fish Farm, Cease-Fire Line, Oasis, Wharf, Communication Tower ? All there as well. You can even find out where the cranberry bogs are located in your area !

There are several desktop free and commercial visualizers of this data .. but I’m interested in unlocking this data for web based mapping and worldKit. One option is the open source mapserver, which Schuyler and Jo used to present VMap0 data on locative.us.

But how to get at the actual geo objects, the polygons, lines and points in this data? First I downloaded the huge tarballs, from links on mapability. The entire mapability tutorial gives a great introduction to the available data, and is a useful guide for doing queries later on.

From hints on irc geo channel, I found that the OGR toolset can read vector map files, including VMap0. Thankfully, OGR plus other necessary and supporting libraries and tools (including mapserver) has been packaged and compiled in FWTools. Downloaded and installed without problem.

Then I had to find out how to use these powertools. This description of vector support in OGDI provided the last piece of the puzzle. I ran a command similar to

ogrinfo gltp:/vrf/usr4/mpp1/v0eur/vmaplv0/eurnasia ‘polbnda@bnd(*)_area’

and out came loads of parseable text of the coordinates for all internal country borders in Europe and North Asia.

For a demo, I produced RSS from two queries for maps of airports in Europe and North Asia and regions in Sweden. There is a lot of data, so it might take a moment to load. The polygons in the Sweden map demo some of the new features under development.

Not sure of the best way to build this data into worldKit. Thinking about: a service to convert VMap0 themes into RSS files. Or into preparsed swf’s. Or a mapserver instance for use with MapProxy. If necessary, wonder how to smooth out the polygons to lower resolution, and remove some of the myriad tiny islands.

Another thing to investigate is the thoroughness of the data. I can’t seem to generate internal borders for north america. Layers like Power Transmission Lines has very spotty coverage, Military Bases are not present at all (not surprising really). Also, a problem to solve is how to join regions split by the tiling of the data set (the source of the vertical and horizontal lines in the Sweden map).