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Global Warming Can be Explained by Depletion of Stratospheric Ozone
Caused by Human Activities and Volcanism

Mean temperatures just above Earth’s surface are thought to result from a delicate balance primarily between two sources of radiant energy: (1) solar energy, most of which warms Earth and its atmosphere directly during daytime, and (2) terrestrial infrared energy radiated outward from Earth 24 hours per day. Some spectral components of terrestrial energy are well observed to be absorbed by greenhouse gases in the atmosphere and are thought to warm the atmosphere, radiating back to Earth as much as 84% (Trenberth et al., 2009) of the infrared energy initially radiated by Earth. But only a small fraction of this terrestrial infrared energy is actually absorbed by greenhouse gases and less than half of that can be radiated back to Earth because radiation extends in all directions. Furthermore temperature in the troposphere decreases with altitude and a colder blackbody in the atmosphere cannot radiate back to Earth frequencies and amounts of energy high enough, according to Plancks law, to raise temperatures on Earth. You do not stand by a cold stove to get warm.

We explore here an alternate theory, that changes in mean temperatures on Earth result from changes in the mean amount of solar energy reaching Earth’s surface determined primarily by changes in the mean amount of ozone and of volcanic aerosols in the lower stratosphere. While greenhouse gases are well mixed throughout the atmosphere, ozone exists primarily in the lower stratosphere where concentrations vary regionally by 10% to as much as 50% on time scales of hours, seasons, decades, and longer. The catalytic processes of photodissociating and forming ozone again absorb solar ultraviolet energy, increasing the temperature of air very efficiently, over and over, heating the stratosphere. When the normal amount of ozone is depleted, less ultraviolet energy from Sun is absorbed in the stratosphere, the stratosphere cools, the tropopause rises, and more ultraviolet energy reaches Earth warming primarily the ocean and thereby raising mean surface air temperatures.

We document that the times and locations of major global warming observed over the past 60 years are contemporaneous with and co-located with the times and locations of greatest ozone depletion caused both by human activities (~3%) and by volcanic eruptions (~6% each), even small basaltic extrusive eruptions. Ozone depletion caused by humans and by two small, basaltic volcanoes in Iceland erupting in 2010 and 2011 totalled 14% in parts of central North America during the time and at the location of unusual warming and drought in 2012 and 2013. Detailed observations of abrupt global warming in recent times and throughout geologic time are explained much more directly by depletion of stratospheric ozone than by changes in the concentrations of greenhouse gases. Based on our analysis, man’s role in global warming may be far more manageable than currently thought.


The text above is the abstract of a paper submitted for publication. When published, this website will be updated to explain the ozone-depletion theory of global warming in much more detail. This new theory explains a broad range of observations much more directly and in far more detail than greenhouse-gas theory.

The rest of this page reflects my thoughts as of 2010. I had discovered that the greatest period of global warming in the past 25,000 years, at the end of the ice age, was contemporaneous with the greatest deposits of volcanic sulfate in glacial ice under Summit Greenland. I first suggested that sulfur dioxide, the precursor of sulfate, caused the warming. In 2011, I began to realize that sulfate in ice cores is simply a proxy for the amount of volcanism per century and that volcanism was depleting ozone, causing global warming.

A paper published in Thin Solid Films, 2009, Volume 517, Number 11, Pages 3188-320

A paper based on a Plenary talk April 18, 2010 to be published in the SVC Bulletin, Summer, 2010

Related talk given in 5 cities April-May, 2010

From the IPCC Consensus February 19, 2009

Public Lecture in Jackson, Wyoming, February 22, 2009