Weather Pix – 08-Feb-2010

Summary: Approximately 2.5 inches of snow fell in the early to mid morning hours. Photographs taken by Derrick Wales at approximately 10:00am 6 miles southwest of Prospect, TN, just north of the AL/TN stateline.

The Deadly Cycle – How Global Warming Causes Global Warming

The Deadliest Cycle – How Global Warming Causes Global Warming

It is a process known as “feedback”. This process involves some sort of action or event which triggers another event which worsens the first event leading to another secondary event which worsens the first event even more. Confusing? I’ll explain.

A good example of feedback is the melting of the polar ice caps and it’s involvement with global warming. The ice naturally reflects heat energy in the form of radiation back into space. As the ice melts, it covers less area and reveals more water coverage. Less ice enhances the atmospheres heat energy (ice cools air just like it cools your summer drinks). With less ice, the remaining ice melts faster revealing yet more water. Water absorbs heat energy instead of reflecting it. This causes the ice to melt even faster.

There are several types of natural “feedback”: Ice Albedo feedback, water vapor feed back, arctic methane feedback, lapse rate feedback and more. These feedback types enhance global warming and are also, simultaneously, caused by global warming to some extent.

Ice Albedo Feedback
As discussed earlier, Ice Albedo Feedback involves the fact ice reflects more radiation than it absorbs. When ice melts it is replaced by land or water which absorbs more than it reflects. This causes more heat absorption which causes more ice melting which causes yet more absorption. This cycle is never-ending unless affected by an outside source.

Water Vapor Feedback
Water Vapor is a Greenhouse Gas. As the earth warms, more water is evaporated leading to more water vapor. More water vapor leads to more warming which leads to more evaporation thus more water vapor. This cycle is never-ending unless affected by an outside source.

Lapse Rate Feedback
Temperature differences between the lower atmosphere and upper atmosphere is called the Lapse Rate. The higher the temperature of the upper atmosphere, the more radiation is emitted. Thus, if the upper atmosphere (which is supposed to be cold) is heated, it emits much more radiation than if it were cold. This cycle is never-ending unless affected by an outside source.

Methane Release
Warming of the earth has effects both on land and in the ocean in the form of methane release. As the earth’s temperature increases, certain areas of permafrost on the earth melt releasing long frozen and stored methane gas, which in turn, causes more warming since it’s considered a greenhouse gas. This cycle is never-ending unless affected by an outside source.

Cloud Feedback
Some types of clouds, particularly cumulus, are expected to increase in frequency and coverage in the future due to warming and higher, faster evaporation rates. Clouds of this type tend to reflect radiation back down to the ground thus enhancing the lower atmosphere’s ability to retain heat. This increases the earth’s temperature even more causing more cumulus clouds and more back-to-earth radiation reflection. This cycle is never-ending unless affected by an outside source.