Greenhouse Gases and Global Warming?
Global Warming is a hot and debatable topic. Everyone agrees the temperature is going up. Scientists attribute the current warming to many issues. There are two main points of argument. First, are we just in a global warming pattern similar to other warming events near ice ages. Or the opposing view that the influx of greenhouse gases most notably CFC's coupled with destruction of the rainforest, and general pollution are the reason for the current warming.
The figure below shows the radiation balance of Earth. This is what is referred to as the greenhouse effect. Energy passes through the glass of the greenhouse (atmosphere) and is absorbed by the materials inside (Earths surface). The radiated heat inside this greenhouse cannot pass freely through the glass (greenhouse gases) and the air under the glass is then warmed (lower atmosphere greenhouse effect). (Oliver and Hidore 32)
http://ublib.buffalo.edu/libraries/projects/cases/petition_notes.html
The graph below shows the rising of CO2 concentrations at Mauna Loa, Hawaii. This spot measures CO2 because it is close to the equator and has lots of vegetation not skewing the data. CO2 rates are rising by about 0.5% per year. This correlates with the recent warming temperatures. The 1990's were the warmest decade on record and 1998 the warmest year on record. Humans have significantly added to the greenhouse gases adding about a quarter more then before the Industrial Revolution. But all this doesn't mean that the Earth will continue warming especially since scientists don't know what the changing atmosphere will be like. Untested complex computer models are fueling many people's opinions and make great news stories but no one know if these models properly integrate all the variables.
C.D. Keeling and T.P. Whorf, Carbon Dioxide Information Analysis Center, August 2001
http://www.daviesand.com/Choices/Precautionary_Planning/New_Data/index.html
This graph shows the great correlation between CO2 and temperature.
The other side of the coin is the opinion that the Earth is just in a normal Ice Age pattern. The Earth has experienced many Ice Ages since it's birth. Generally, right after an Ice Age a trend of significant warming takes place. Some theorize that we are just in one of those warmings now. The above graph shows the Ice Ages and their warmings immediately after. Take the ozone hole for example there is no real correlation that CFC's effect the ozone hole, some believe that it is just part of a cycle of the Southern Polar Vortex. A lot of scientists are reluctant to share their views since some of their funding could be cut, which cuts their programs. But the global warming topic is ever-changing and makes a great lead in story on the evening news. What is important to remember is that there is two sides to this story and more research and better models need to be done, to better predict our future climate patterns and infrastructure.