Models and simulations can be a difficult part of the ITGS syllabus, with relatively complex issues surrounding the reliability of models, missing variables, assumptions, and so on. The four examples below are all interactive models that should help refresh your mind about the purpose of models and their applications. Several of them also link to the Education and Training scenario, as they are good examples of how computer software can be used to improve teaching and learning.
While you are using them, keep in mind the following questions:
What processes are being modelled?
What variables are being modelled?
Are there any processes that might have been simplified?
Are there any variables which might affect the result but as not in the model?
Climate models are the canonical example of computer models. The Habitable Planet’s Carbon Lab is a model of the Earth’s carbon cycle, complete with variables for fossil fuels consumption, deforestation, and other factors. When you can finished playing the model, you can read this article to see how climate models are used in the real world.
The Habitable Planet is up again, this time with their ecology model. You build up the food chain by selecting each animal’s primary food source (there are three plant types, two herbivores, two omnivores, and one top predator), and then run the model to see what happens to each animal’s population. Get it wrong and all species may die out – get it right and the numbers should fluctuate a bit before evening out. Then you can read this news article (BBC) about how computer models were used when considering whether or not to reintroduce wild wolves to Scotland.
Northwestern University has a large range of computer models on its web site. This example models the spread of the Human Immunodeficiency Virus (HIV) with a population. As the model is run, differing numbers of red, green, and blue people represent respectively those whose status is HIV positive, HIV negative, and unknown. Variables including the average relationship length and the frequency of HIV testing can be changed.
This computer model from Germany models traffic flow at various types of junction (intersection). Altering the traffic flow, type of traffic (trucks or cars), and road type results in different levels of congestion. This is a good example of how even relatively unpredictable concepts – such as human behaviour – can be mathematically modelled to give a likely outcome.