GIS in the mountains!1 mars 2007
This is a brief description of what I’ve been doing at school lately. The assignment was to do some analysis with GIS, preferably using application handling raster imagery (IDRISI) instead of vectors (MapInfo). Me and my two friends decided to work with mountain huts in Jämtlands län in the swedish mountains. The swedish tourist organisation (STF) hosts a couple of mountain lodges around the swedish mountains where everyone can stay. Well, if you pay, of course. The system is similar to youth hostels but without electricity.
Anyway, for quite a while now I’ve been thinking of where STF might locate new huts. Since I love maps I’ve been studying the maps over the area a lot and seen places that could be nice spots to place another hut.
That’s what we did! By using GIS, based on elevation, inclination, distance and different types of surfaces, we managed to decide where new huts should be located.
First we called a dude at STF and asked him some questions. Apparently the current distances between huts are too long, according to modern hikers. So instead of focusing on routes that are between 13-20km, we had to lower the distance to between 8-12km i think. I say I think because what we did was to create a ”friction” map where each pixel represented 50 meters. And then we gave each pixel a number, which was the time it takes to walk that 50 meters on that location. If the pixel was a lake, then it took maybe 2000000 seconds to walk it (just so that the software wouldn’t try that direction). Also depending on the inclination the pixels got different values.
This is the inclination map.
This is the inclination map. Dark areas means impossible to walk, brighter colors are easy to walk.
Then when we had the friction map, we placed the existing huts on the map and created a so called COST map which showed the amount of seconds it takes to get to each pixel.
COST-map of one hut.
Then we simplified it so that it only showed the times that we were interested in (around 5h walk).
COST-map with only two classes.
Same but another hut.
After we’d done all 25 huts and small villages we put them on top of each other to see where we could find a match. Where there was a match of more than two huts, we had a spot! This because we wanted the new location to be accessible from at least two existing huts.
Good places. Darker red means better location!
Our location zoomed in.
Finally we decided on location our new hut just north of the big lake in the west. This because you could reach it from four different places!
Finally, the amazing flow chart.