Global Warming – Greenhouse Gases and Climate
Name : Global Warming – Greenhouse Gases and Climate.
Category : Energy & Environment
Files Source: www.pitt.edu
File Added : June 4, 2010
Size : 1.75 MB
Download : 352
An online presentation about global warming. Consist of material Greenhouse Gases and Climate, Global temperature trend, The (Atmospheric) Greenhouse Effect, Atmospheric Carbon Dioxide, Feedback Effect, How fast will the CO2 concentration increase, Some examples of criticisms
Content summary :
“According to the National Academy of Sciences, the Earth’s surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades. There is new and stronger evidence that most of the warming over the last 50 years is attributable to human activities. Human activities have altered the chemical composition of the atmosphere through the buildup of greenhouse gases – primarily carbon dioxide, methane, and nitrous oxide. The heat-trapping property of these gases is undisputed although uncertainties exist about exactly how earth’s climate responds to them.
What cause the temperature of the atmosphere to go up?
* There are many possible mechanisms that can cause the warming of the atmosphere, for example:
o Natural variation – the climate becomes warmer by internal chaotic dynamics of the earth-atmosphere system (that is, no external influence).
o Solar activity – either direct increase of solar energy output or indirect “trigger” mechanisms due to solar activity (though nobody knows how) may cause the surface temperature to go up.
o Greenhouse effect – increasing “greenhouse” gases such as CO2, CH4, NO, CFC,…etc. (actually H2O is very efficient, too, but at present it is assumed to be in steady state).
* The last one is presently thought to be the most likely cause of the global warming and hence we will examine it here in this chapter…..” Download for more information!!
