the greenhouse effect. some atmospheric basics the greenhouse effect radiant energy that is absorbed...
TRANSCRIPT
The Greenhouse Effect
Some atmospheric basics
• The greenhouse effect • Radiant energy that is absorbed heats Earth and
eventually is reradiated skyward–Radiation is in the form of longwave infrared
radiation
–Atmospheric gases, primarily H2O and CO2, are more efficient absorbers of longwave radiation– This selective absorption, called the greenhouse
effect, results in warming of the atmosphere
The greenhouse effect
IPCC 2007
Why Focus on CO2?
• Only 390 ppm (0.039%) of the atmosphere
The total number of CO2 molecules above our heads in the atmosphere is more important than their percentage in the atmosphere
What are the greenhouse gases?(excluding H2O)
• Carbon Dioxide: 49%• Methane: 18%• “CFC’s from coolants, solvents, etc”: 14%• Nitrous Oxides: 6%• Others: 13%
Most outgoing Earth radiation is intercepted and absorbed by greenhouse gases like water vapor, methane, and carbon dioxide.
