The Role of Greenhouse Gases in Energy Transfer in the Earth’s Atmosphere

By W. A. van Wijngaarden, Department of Physics and Astronomy, York University, Canada and W. Happer, Department of Physics, Princeton University, USA

We discuss the basic ways greenhouse gases affect radiation transfer in Earth’s atmosphere. We explain how greenhouse gases like water vapor, H2O, or carbon dioxide, CO2, differ from non-greenhouse gases like nitrogen, N2, or oxygen, O2. Using simple thermodynamics and fluid mechanics, we show that the atmosphere of a planet with sufficiently high concentrations of greenhouse gases must develop a convecting troposphere between the surface and the tropopause altitude. The planet must also develop a non-convecting stratosphere for altitudes above the tropopause. In the simplest approximation of an atmosphere that is transparent to sunlight and has frequency-independent opacity for thermal radiation (an infrared gray atmosphere), one can find simple formulas for the tropopause altitude, and for the altitude profiles of pressure and temperature. The troposphere is nearly isentropic and the stratosphere is nearly isothermal. The real atmosphere of the Earth is much more complicated than the simple model, but it does have a troposphere and a stratosphere. Between the surface and the tropopause the entropy per kilogram of real tropospheric air increases slowly with altitude. The entropy increases much more rapidly with altitude in the stratosphere. The stratosphere has a nearly isothermal lower part and a hotter upper part due to absorption of solar ultraviolet radiation by ozone. The thermal opacity of the real atmosphere has a complicated frequency dependence due to the hundreds of thousands of vibration-rotation transitions of its greenhouse molecules. Unlike the simple model where nearly all radiation to space originates at the tropopause altitude, radiation to space from Earth’s real atmosphere originates from both the surface and all altitudes in the troposphere. A small additional amount of radiation originates in the stratosphere. When these complications are taken into account, model calculations of the thermal radiation spectrum at the top of the atmosphere can hardly be distinguished from those observed from satellites.

You may download a printable version of The Role of Greenhouse Gases in Energy Transfer in the Earth’s Atmosphere


Wyoming and Climate Change: CO2 Should Be Celebrated, Not Captured

EXECUTIVE SUMMARY This report examines the actual and projected effects of the climate on the State of Wyoming in response to proposals to reduce emissions of carbon dioxide (CO2) through the use of “carbon capture” in order to avert purportedly catastrophic atmospheric warming. This research concludes that Wyoming – like the planet – is benefiting… Continue Reading

UCLA Law School Unethically Promotes an Anti-Science Climate Emergency

Statement by Dr. James Enstrom concerning unethical practices of the UCLA Law School 11/6/23   UCLA Law School Unethically Promotes an Anti-Science Climate Emergency By Dr. James Enstrom – PhD in physics, Stanford University Please read my November 2, 2023 email letter to the UCLA Law School Dean Michael Waterstone. It is very important to… Continue Reading

Subscribe to Our Informative Weekly Newsletter Here:

  • This field is for validation purposes and should be left unchanged.