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Introduction to the simulation

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Imagine a system made up of

• a reservoir, like the atmosphere
• a source of pollutants, like the emission of carbon dioxide from combustion
• a sink for the pollutant, like the removal of CO₂ from the atmosphere by its dissolution in rain water

Such a system could be simulated using an equation like

[X]_t = [X]_t-1 + R_in - R_out

which effectively says that the concentration of X at some time, [X]_t, can be calculated if we know

• the concentration of X at some earlier time, [X]_t-1
• the rate at which X is being added to the reservoir, R_in, and
• the rate at which X is being removed from the reservoir, R_out.

Further technical details on the simulation are given later, but now it is time to explore the simulation for yourself.

At this stage you should download the Excel spreadsheet, 'simulation.exe', if you have not done so already and investigate it. When you have finished you should come back here to continue with the Web pages.

If you do not have access to Excel, you should simply continue with the Web pages.