Temperature Response to Increased Atmospheric CO2
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      This animation illustrates the changes in surface air temperature
that result from increasing levels of atmospheric carbon dioxide.
These results are derived from two extended computer simulations using
a comprehensive numerical model of the Earth's climate system developed
at NOAA's Geophysical Fluid Dynamics Laboratory.  In these simulations,
atmospheric carbon dioxide increases at 1% per year from the modern-day
level at year 1 of each experiment to double that level in year 70 of
the first experiment, and to quadruple that level at year 140 in the
second experiment.  After that point, atmospheric carbon dioxide
levels are held constant.

      The colored shading represents the difference in the surface air
temperature between the simulations with increased CO2 and a control
simulation using the same model with today's levels of atmospheric CO2.
As indicated by the shading, warming is more rapid over the continental
regions than over oceanic regions, and is larger in polar regions than
at lower latitudes. Note that warming trend continues well past the
time at which CO2 concentrations level off.  This delayed warming is
due to the influence of the world's oceans, which store and release
heat over very long periods of time.