Posts tagged elevation
Kim Buike, Depiction Board Member and Instructor teaching an on-line Masters course on Depiction Mapping Software for California State University Long Beach, has prepared a tutorial for his class on how to find, download and import into Depiction 10 meter elevation data. The elevation data currently available through the Depiction Quick Start is 30 meter data. Having higher resolution elevation data will make the various simulations that Depiction can perform much more accurate. You can find the tutorial here.
We have restored our Geoserver and have the Elevation Quickstart working again. The other quickstart data sources we provide from our server still aren’t available but we are working to get them restored.
Problems seem to happen in threes. First our geo-server went down, then USGS changed the location of their elevation data and now Yahoo has changed their API which is what we used for geo-coding the starting location for new Depictions. Existing long time users may not notice either of these problems if they are creating new depictions in their home areas because the data may still be in their cache. However, new users and trial users will definitely notice this as will new DepictionPrep users. We have a fix for both problems and the current download on the website is an interim build 12522 which fixes these issues. We will be coming out with an official build next week but if you are experiencing these issues then you can download the new version from the website. We have noticed that the new USGS elevation source is very slow. Apparently they are now returning 1 degree tiles that are 250mb in size and if your boundary happens to cover more than one tile then you could have to download multiple tiles. We hope to have our geo-server up and running next week and so we can have reasonable elevation download times.
It appears that all of our data sources are changing. Now the initial location geo-coding has ceased to function. We use Yahoo and they recently changed their API (application program interface) which caused our malfunction. We hope to have a fix for this in the next day or two. We have actually fixed the problem and are in the process of testing the build to make sure it is OK. We have also fixed the Elevation Quickstart data source. Unfortunately they changed how they are serving out the data and give it out in 250mb chunks and so it takes much longer for it to download. Existing users won’t notice much of a change if your elevation data is in your cache for your area but new users will certainly experience this. We are working to find a solution to this problem as well. We are sorry for any inconvenience these problems cause you.
If you attended our recent Webinar on creating Rapid Situation Maps, we were a bit embarrassed when we found that elevation data wasn’t loading. At that moment we blamed it on a new Beta build that we were running but as it turns out the service where we get the data changed their API and so the elevation quick start source wasn’t working for any build. We are in the process of fixing this problem and will be putting out a new build as soon as we can. If you have downloaded elevation previously for your area then it will probably still be in your cache but if you are a new user or are doing a Depiction in a new area then you will run into this problem. You can still get elevation data directly from the USGS web site. Watch this webinar recording to find out how.
Videos of our November 28th and December 5th webinars are now available on our web site. The November 28th webinar covered Depiction and OpenStreetMaps and the December 5th covered how to download higher resolution elevation data form the National Maps website.
Some of Depiction’s coolest simulation features make use of elevation data–floods, runoff, antennas and more. In the USA, we’re blessed with excellent elevation data available both from Depiction’s Quickstart and, in higher resolutions, as a download from the USGS.
Things have been a bit tougher elsewhere in the world–the ASTER-GDEM data is useful, but its distribution license means we can’t make it available as a Quickstart source.
But thanks to the good folks here, we are now able to make 90-meter data available through Quickstart for many countries. Specifically, you will find it if you create a depiction in any of these countries:
- United Kingdom
- South Korea
- United Arab Emirates
Be warned, 90-meter data means that it is based on measurements taken at 90-meter intervals, so this data is very rough and not very pretty. It also is going to make small-scale simulations even less accurate. However, we do think that it is better than nothing for a variety of purposes, and hope our users around the world are able to make good use of it.
Would you like this 90-meter data available for another country? Let us know!
The tireless Kim Buike has put together three new tutorial videos that are really excellent–if you own the software, you really should take the time to watch these, as it will enhance your understanding of the software even if you’ve used it for a while. If you don’t own Depiction, you should still take a look–they give a good demonstration of Depiction’s powerful capabilities.
First up is “Depiction Elements Explained,” which goes through the different types of elements that make up a depiction.
“Route Elements Explained” gives a great overview of the way Depiction route elements function.
Finally, “Elevation Data Retrieval” outlines how you can easily retrieve high resolution elevation data from the USGS website and import it into Depiction.
Here are the various online resources that we discussed in the webinar today:
- ASTER GDEM Worldwide elevation data
- Geocommons Finder
- Ushahidi Haiti
- Main Ushahidi website
- USGS Shakemap Scenarios
- Crisis Mappers Google Group
- Depiction Crisis Mapping Webcast, April 7
- Depiction 101: Custom Elements & Importing Spreadsheets, April 14
Thanks to everyone who attended!
UPDATE: You can now download the video from the webinar (a 122 MB WMV file). We will have a streaming version up soon.
One question we get frequently from folks who are just seeing Depiction for the first time is “Is it just the US, or is it worldwide?” Depiction is certainly worldwide–wherever you have data for, Depiction will happily plot it.
Of course, one of the most useful parts of Depiction is our Quickstart data, and much of that, admittedly, is limited to the United States. NASA Landsat imagery is worldwide, and OpenStreetMaps is most definitely worldwide, enabling our routing and route-based simulation to function all over the planet.
But one thing noticeably lacking from our Quickstart list is elevation data outside the US and Canada. Fortunately, there is a relatively simple way to get data just as good as our US data for anywhere on Earth.
It’s called ASTER-GDEM, and it is a joint project of the Japanese Ministery of Economics, Trade and Industry (METI) and NASA. As it happens, the Japanese site is much, much easier to use.
There are four ways to choose tiles–you can simply click on 1 degree by 1 degree tiles to select them (click ’start’ to begin); you can draw a polygon (again, click start), you can upload a shapefile, and it will bring in the associated areas, or you can manually enter the coordinates of the area you want. However you do it, you will recieve a visual representation of the tiles you will be downloading, and you can use the “manually select tiles” option to add or remove tiles. Up to 100 tiles can be easily downloaded at a time, in a zip file full of zip files. The data itself is in GeoTIFF format, which loads nicely into Depiction.
One note–you will have to register (which is free) and commit to using the files in particular ways, but the restrictions are very broad.
I can’t promise that we will add this to the Quickstart menu, in part because of the restrictions just mentioned, but the website is the most user friendly way I’ve ever seen of retrieving elevation data–Seamless server, eat your heart out.
I hope to put up some sample depictions using this worldwide data soon–but in the meantime, you should try it out and submit your own!