Vital Climate Graphics - Update

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VITAL CLIMATE CHANGE GRAPHICS

A climate model can be used to simulate the temperature changes that occur from both natural and anthropogenic causes. The simulations in a) were done with only natural forcings: solar variation and volcanic activity. In b) only anthropogenic forcings are included: greenhouse gases and sulfate aerosols. In c) both natural and anthropogenic forcings are included. The best match is obtained when both forcings are combined, as in c.

The information presented on this graph indicates a strong correlation between carbon dioxide content in the atmosphere and temperature. A possible scenario is when anthropogenic emissions of greenhouse gases bring the climate to a state where it reverts to the highly unstable climate of the pre-ice age period. Rather than a linear evolution, the climate follows a non-linear path with sudden and dramatic surprises when greenhouse gas levels reach an as-yet unknown trigger point.