Geographical information systems

Emergency operator, how can we help? A man’s fallen. Send help! Okay, and where are you? 43 Forest Road Help is on the way.

An accident just happened, and the ambulance is in a hurry. It has to take the fastest way. The fastest way, hmm, - isn’t that the same as the closest way? So, here is the hospital, there is 43 Forest Road. The closest way … there!

Straight ahead, almost. But no, that’s a bad logging road. It’s rough and bumpy. We need another path. Quickly now!

This one? No, roadworks! The road is closed. The ambulance needs to find another road. Here?

Yes, this way we should be able to get straight there, Come on, hurry up! To find the quickest road to the site of the emergency scene the operator placed several maps on top of each other. The first one was a map of the roads in the town. The next sheet added information about what the roads were like. And on the third sheet, we could see all the roadworks in the town.

We could see where vehicles can, and cannot, pass. So, we added sheets with new information to the geographical map. The maps and the sheets formed a geographical information system, or GIS. Geographical information systems are saved in computers--they are digital. The maps and sheets contain information, or data.

The maps and the data can be combined in different ways to answer questions, such as: “Which route is the quickest?” The answer to the question is an analysis. The information on the maps can be used for many different analyses. This map shows the island of Borneo’s rainforests in the year 2020. That’s the green. Now we add a sheet with lines.

The red shows where there were rainforests in 2000. And the yellow lines show where they were in 1950 - a much larger area. So, we can see how much rainforest has vanished over 70 years. This geographical information system describes change. Here is a city map with lots of roads.

Now, the authorities in the city are thinking about the future. They need to know where the road is most worn down and will have to be repaired. So, we add information, and each road gets a colour. Green means that few vehicles pass every day. Light traffic.

Yellow means that a few more vehicles pass. And on the red roads, the traffic is heavy. Many vehicles pass every day. So, the red roads will probably be most worn and break soonest. These roads will soon need new asphalt.

This system can be used to make a prediction for the future. And the maps can be used for other analyses. Where do we need new roads the most? Where should the traffic police be visible? The system is used for planning and for distributing resources.

We have seen three different geographical information systems, which have been used to: plan describe change make predictions distribute resources And there are plenty more possibilities. Oh, there you are! You alright now? Yes, the ambulance got here in good time. Thanks to an efficient geographical information system.