Global warming, or what is now often reffered to as global climate change, is one of the most polarizing issues of our time. In this article, I will attempt to explain the basic physics of global temperature changes, how we are attempting to measure and predict them, the alleged consequences (and even possible advantages) of global warming, the “solutions” to slow it, and the potential impacts of such measures on our lives.
1. The physics of global temperature.
The sun (shortwave) radiation warms the earth while outgoing (longwave) radiation cools the earth. The energy coming in from the sun is fairly constant, and the energy going out from the earth is proportional to the temperature on earth. The earth’s average temperature is the value that allows an exact balance between incoming shortwave, outgoing longwave, and absorbed and reflected radiation.
“Greenhouse gases”, like carbon dioxide (CO2), absorb some of the outgoing energy, keeping the earth warmer. Interestingly, high clouds do the same thing, while low clouds do the opposite. Some other gases, like sulfur compounds, reflect sunlight and keep the earth cooler. The primary assertion by those who are concerned about anthropogenic (manmade) global warming “AGW” is that the increase in atmospheric CO2 since the industrial revolution began has also caused a warming of surface temperatures through the greenhouse effect, and the warming will continue. However, natural occurrences have also caused changes in CO2 and periodic warming way before the industrial revolution. According to geologists, an ice age once brought glaciers down into the present-day northern U.S. and created the Great Lakes. The earth warmed after that, and it wasn’t a power plant causing it. Scientists also tell us of a warmer time in the past, when sea levels were much higher due to melting polar ice, when the Gulf of Mexico came up to about Montgomery (they have found manatee fossils in Auburn). Again, no power plants. Since people produce CO2 everytime we exhale air, we are also contributing to global warming by breathing. Ok, bad joke.
Source Link: alabamawx.com