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Interactive Labs

Carbon Lab

Tools of the Simulator

Simulator Controls

Reset Button
Reestablishes original settings of the simulator, including simulation parameters, graph, and illustration.
Run Decade
Simulates the progress of the carbon cycle at its current settings for ten years.

Simulator Parameters

Change in fossil fuel use per year
Use your mouse to move the green square, which represents the range of percent change in consumption per year. Moving to the left decreases the percentage change of consumption of fossil fuel from the default and moving to the right increases the percentage change.
Note: You are changing the percentage from the current use. If the current use of fossil fuel is 1.5% of all the energy generated in the world, and you lower it, theoretically you would be changing energy generation from fossil fuels to some other form (wind, solar, biofuel, etc) since the total amount of energy generated stays the same.
Deforestation rate per year
Use your mouse to move the green square, which represents the range of the rate of deforestation per year. Moving to the left decreases the rate of deforestation from the default and moving to the right increases the rate of deforestation. Note that deforestation is expressed as GT of carbon released, not as a percentage rate of increase. Realistic deforestation estimates would remain less than 2 GT per year.
Clicking on this button set fossil fuel use at zero, meaning that all energy, worldwide, will come from some energy source other than fossil fuels.
Year and numbers
The year tells you where you are in the progression of the simulation. The default begins with year 2000. The set amount of carbon released from fossil fuels is listed below the year in gigatons, which is abbreviated as GT.


The Atmospheric CO2 graph shows the progression of the carbon cycle and the amount of atmospheric carbon produced per year in parts per million, abbreviated as ppm. One part per million (ppm) means that for every 999,999 particles in the air, one particle is carbon dioxide. The legend box may be moved by dragging it with your mouse. The y-axis is the amount of atmospheric carbon generated each year.

There are four lines on the graph: IS92a, CO2, Now, and Goal.

This line represents one of the IPCC (International Panel on Climate Change) 1992 Supplement Report's six scenarios for how Carbon Emissions would likely develop in the future. Because of uncertainty in terms of population growth, economic growth, technological advances, responses to laws and restraints, and other human factors, six scenarios were developed, and IS92a is the most moderate of the six. This model assumes a modest population growth, modest economic growth and that only those controls on emissions already enacted into law by 1992 would be obeyed. This model is called "business-as-usual," and while you are running your simulation, it will continue to project carbon emissions over the years with modest growth and modest controls on emissions.
This line is the amount of carbon emitted per year according to the parameters you set for running the simulator. As you change parameters, the slope and general shape of this line will change as well. This line is directly correlated to the illustration, and especially to the number in the middle of the sky on the right hand side, which says XXX ppm CO2. That number is also the number plotted on the graph by the CO2 line.
This refers to the diamond on the line. The diamond tells you what year it is at the current moment within the world of the simulator.
This line refers to the goal of 550 ppm CO2, which would be twice the amount of atmospheric carbon in comparison to pre-industrial levels. The IPCC established this number as a goal, hoping that carbon emissions can be stabilized at this number instead of continually rising as they have done since the advent of the Industrial Revolution.

Simulator Illustration

All numbers refer to the amount of carbon present in that area. The plus or minus numbers show the change from the original setting over the past decade run in the simulator. The scale is at the top, on the right hand side: one grey rectangle equals 25 gigatons (GT) of carbon.

Carbon cycles in this illustration in an almost perfect oval, so that emissions from the smokestack are transferred to the atmosphere, from there to ocean surface, from there to the deep ocean, and so forth. There are also other pathways, for example, from the soil to the ocean and vice versa.

The smokestack number
This number represents the amount of human-generated carbon emissions per year. Even with controls in place, this number increases annually.
XXX ppm CO2
This number represents the total amount of atmospheric carbon at that time, based on the parameters that have been established. This number is also what is being plotted simultaneously on the graph as the simulator is run.

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