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Radiative Forcing, or RF, is specifically defined as the change in net irradiance
at the tropopause after allowing for stratospheric temperatures to readjust to
radiative equilibrium, but with surface and tropospheric temperatures and state
held fixed at the unperturbed values. In layman's terms, RF refers to an
imbalance between incoming solar radiation and outgoing infrared radiation that
causes the Earth's radiative balance to stray away from its normal state.
This straying causes changes in global temperatures. Furthermore, the units of
Radiative Forcing are watts per square meter, and, if the value is positive, it
has a warming effect on the climate, whereas if the value is negative, it has
a cooling effect. If there is more radiation coming into the atmosphere than is
escaping, that radiation becomes trapped as heat energy. This is exactly what
we are seeing in our planet's ecosystem today, and these changes in temperature
effect all earthlings, from real estate agents to ruby throated
hummingbirds
As stated above, RF is an important tool used to determine the effects that
greenhouse gases, aerosols, and clouds have on climate change. However, RF does
not depict the climate response in its entirety. There are several parameters
related to climate change that exist, but they are greatly variable and complex.
In the same sense that a designer must make the right calculations to do
his/her job right, RF must be calculated accurately. Since RF is easy to calculate,
it provides a general, yet respectable, estimate of how the climate will respond
to changes in greenhouse gas concentrations and various other agents.
So how is Radiative Forcing calculated? For the most part RF values are estimated
using data from what is referred to as General Circulation Models (GCM's). These
models use numerous methodologies, live
leads and histories to get their numbers. Radiative forcing is intended
as a useful way to compare different causes of perturbations in a climate system,
and anyone can learn to perform these estimates, just as faux
painting instruction may help you try something new, learning how to do
RF calculations may enlighten you on the topic of climate change, and what you
and your family or coworkers can do about it.
RF calculations are based on shorter-term changes in forcing due to natural
and human-caused events, since so many of the Earth's changes occur over
such a long time frame, they are assumed to be constant. This is similar to
the effects of applying heat, without the variable of
heat (the constant), the sleeve does not work. It is essential to have all
of the elements and geological data in place to have accurate RF estimates.
In today's atmosphere, the effects caused by human activities
are much more influential on climate change than the RF caused by natural phenomena,
such as volcanic eruptions and solar changes. Thus, it appears as though humans
may want to reconsider the amount of greenhouse gases that they pump into the
Earth's atmosphere because it obviously has a measurable effect on climate
change.
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