Cause-Effect Flowchart

The flowchart (layout menu) demonstrates the chain of calculations in the model, and thus the cause-effect relationships between the components of the system.

You can adjust controls and menus on the plots as usual. The arrows will change, depending on which options you have chosen.

Normal sequence

The normal cause-effect sequence is:
Mitigation or SRES scenarios
(=>Regional emissions)
=>Carbon cycle & Other gases
=>Radiative forcing
=>Temperature
=>Sea-level & Regional climate

However there are some feedback processes which go the other way. For example, the carbonate-chemistry in the ocean is affected by the temperature, if the "CF" button in the carbon cycle plot is enabled. Disabling this removes the arrow from temperature to carbon, and increases the ocean carbon sink, also removing the "spikes" due to historical temperature variability.

  • More about this feedback

    What is changing?

    Red arrows on the flowchart indicate cause-effect flows that were changed by your last action (dragging a parameter, selection from menu, etc.). The module directly affected by the parameter is shown with red text. Yellow arrows show dependencies that didn't change.

    For example, if the temperature-carbon feedback (CF) is enabled, and you also choose to "stabilise concentration" from the emissions menu, then adjusting climate sensitivity will affect both carbon and emissions, so most of the arrows are red. If it is disabled, adjusting an uncertainty control on the temperature plot (e.g. climate sensitivity) has no effect on carbon or radiative forcing, so the arrows in the upper part are yellow.

    Note the model only calculates the components that have changed, and are also needed by visible plots. So you may notice, that the more red arrows there are, the slower the response is.

    See also:

  • How it works so fast
  • Model code structure

    Mitigation and SRES effects

    If you choose to stabilise CO2 concentration or temperature (mitigation menu), then there is a feedback from carbon or climate back to mitigation, which attempts reach the target curve (controlled by the four-headed arrow). If you choose to stabilise emissions, carbon and oghga are still controlled by mitigation, but there is no feedback. If you choose SRES no-policy scenarios, then mitigation does nothing, everything starts from SRES.

    See also:

  • how CO2 stabilisation works
  • emissions options
  • different approaches

    Regional emissions are affected by mitigation and SRES. The regshares module calculates the distribution, but doesn't affect the total.

    SRES affects several parts of the model, depending on options in the Mitigation, Distribution and Other Gas menus.

  • Population, GDP and Energy (people)
  • Regional CO2 emissions (regshares)
  • Land use change CO2 emissions (carbon)
  • Other gases & aerosol emissions (ogha)
    See also
  • the SRES scenarios
  • distribution options
  • Other gas emissions

    Eventually, our aim is to complete the right hand side of the circle, to show how regional emissions policy may be affected by anticipation of regional climate impacts, and how regions may achieve a better result through global cooperation.

    The responsibility and costs modules anticipate further developments.

  • See future work