Although it is true that squeezing air warms it, the pressure does not set the temperature (change in pressure bringschange in temperature), and, the greenhouse gases are really very rare and don’t affect pressure much. Clouds are not caused by greenhouse gases, and while clouds warm nights, clouds cool days, and the net effect of clouds is probably slight cooling of the planet. Convection currents are blocked by the glass of greenhouses, but not by greenhouse gases. But CO2does absorb some of the infrared radiation emitted from the planet. Absorbingan infrared photon puts a CO2molecule into an excited state, and fairly quickly the molecule returns to its unexcited state by emitting a photon of the same energy. Some of those photons emitted by excited CO2molecules head back toward Earth (the emission direction is random). So, the CO2serves to trap energy in the Earth system, warming the planet so that it glows more brightly to shove infrared radiation past the CO2, achieving a new
balance.Table for Individual Question FeedbackPoints Earned:0.0/1.0Correct Answer(s):C11.The United Nations-sponsored Intergovernmental Panel on Climate Change shared the 2007 Nobel Peace Prize. The information that the Panel has supplied to policymakers includes:Table for Individual Question FeedbackPoints Earned:1.0/1.0Correct Answer(s):E12.Regarding global warming, most scientists (including those who
have advised the United Nations through the Intergovernmental Panel on Climate Change) agree that if we continue to burn fossil fuels at an accelerating rate:
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- CO2, Coal, Pennsylvania, Individual Question