Today I want to write about places to find data for your GIS work. The nice thing about the GIS courses I have taken was that I was given the necessary datas to do the exercise work. But when you want to do things on your own, for fun, for learning or as a part of your studies you need some data to work from. So here are some resources I have used to get data.
OpenStreetMap: Maybe the most famous example of Open map data is of course OpenStreetMap. All their data is free to use as long as it is credited. They recently updated their map viewer with a different interface and more map layers. On top of the site is a export button that lists a few different download options. One of those is download.geofabrik.de which I have used successfully, and which offers a selection of layers with the most important features (road and railway network, forests, water areas, some points of interest). Openstreetmap data is also available of any country to use on Garmin GPS devices. I have done that several times, for Norway Germany, France, Romania and Benelux. GPS maps cost a small fortune here, but I’m happy to say that the OpenStreetMap maps work very well, and can even route me on bike trips, or when geocaching. For countries in Europe I have used Frikart.no, and there are many other providers of GPS maps. Here is a guide on how to install them, which is mostly copy-pasting a file onto your GPS or memory card.
Worlds borders dataset: For simple maps, like my EGEA entities map below I just needed a shape file of all the country borders. That can be found here, and that file also has some information like population and area in it. My original source was the second link here which no longer works, but this site still have country level data that seems to work. There is climate data for Europe available here, but I have not yet tried to download from there.
A simple shapefile of borders with a kml file of the EGEA entities on top.
Landsat imagery: One of the things I play around with now is Landsat imagery. Now that Landsat 8 have been flying for 10 months, it has taken images of the whole world. I have used the EarthExplorer tool to find and download satellite imagery, and ESA also have a download site. They also have a bulk download application that makes it easy to download many images. But to download images you need to make an account first (simple registration process) and preferably have a fast internet line available. To use the images they need to be unzipped twice (I use 7-Zip for that). The raster image bands (description here) will look like they are black and white. In order to get a “true colour” composite the red, green, and blue bands have to be composited to a single image. I have used the “Composite bands” tool in ArcMap and selected the right bands (4, 3 and 2, in this order). If you have GDAL, which comes with QGIS you can also follow this good guide.
Example of a Landat 8 “true colour” composite image (click to embiggen).
The Norwegian Mapping Authority: In September the The Norwegian Mapping Authority made public under a creative commons license a lot of data which can be downloaded here. The data available is terrain models (DEM), place names, road network, borders and vector or raster maps in scales from 1:5000 000 all the way down to 1:50 000. A registration is needed, but then you’re free to make nice things like an application to buy a 3D-printed model of a part of Norway which the company Bengler did to celebrate the data release.
Wow, I see I have a lot of links in this post. I hope any of them can be useful to you. If you know about a source of free data that should be included in this post, feel free to comment below.