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Carbon reservoirs and emissions

Compare the carbon amount and balance of the three reservoirs by changing the virtual emissions, absorption, land change, and period.

    E20 · Carbon reservoirs and emissionsReady
    You can also experiment with the numbers and controls below the scene.

    Earth Science · Ocean · Climate · Water Cycle / Principles and Exploration

    Carbon reservoirs and emissions — principles and investigation

    The atmosphere, oceans, and land are repositories that exchange carbon with each other. Change the external emissions, absorption coefficients, land change, and calculation period to compare each storage amount with the sum of the three storages. It is an activity that distinguishes between carbon being transferred between reservoirs and total additions outside the model.

    How does it work?

    Absorption moves carbon to the ocean and land. Land change moves from land to atmosphere but does not increase the sum of the three reservoirs.

    Key relationship

    Δ(A+O+L)=Cumulative external emissions/atmospheric ppm=A/(2.12 GtC/ppm)

    Try this investigation

    1. Perform virtual emissions by looking at the arrows and net flow between the air, ocean, and land. Since the initial values ​​for each storage vary greatly, the graph displays the change compared to the initial value.
    2. We record conditions where external emissions are 10 and 0 GtC/year for 100 years and compare total carbon growth and cumulative emissions.
    3. Keep the annual emissions and only change the absorption coefficient or land change. Compare the atmospheric ppm and the net flow rate of each reservoir.

    Interpreting your results

    If carbon moves from land to the atmosphere due to land change, what is the total amount?

    Land → air is internal movement. The sum of the three boxes increases by the external emissions. A 2.12 GtC increase in atmospheric carbon converts to an increase of 1 ppm.

    Assumptions and limitations

    It is a virtual three-box model starting with GtC of 850 in the air, 38,000 in the ocean, and 2200 on land. A linear absorption/reverse exchange coefficient is applied to the carbon difference compared to the initial value, and land change is calculated as internal movement. 2.12 GtC/ppm is a fixed conversion value. The original reservoir of fossil carbon is outside the model. It does not calculate the complex feedbacks/temperature of the actual carbon cycle and is not a climate prediction.