7 Theories of Climate Change

“At least seven theories of climate change enjoy some support in the scientific community. With the anthropogenic global warming theory now in disrepute, it is a good time to review the other six …”

This booklet identifies seven theories, anthropogenic global warming (AGW) plus six others that do not claim man-made emissions are a major cause of climate change. Each theory is plausible and sheds light on some aspects of climate change that were hidden or obscured by too great a focus on the AGW theory.

The six alternative theories are:

• Bio-thermostat -- rising temperatures and levels of carbon dioxide (CO2) in the atmosphere trigger biological and chemical responses that have a cooling effect, like a natural thermostat.

• Cloud formation and albedo -- changes in the formation and albedo of clouds create negative feedbacks that cancel out all or nearly all of the warming effect of higher levels of CO2.

• Human forcings besides greenhouse gases -- mankind’s greatest influence on climate is not its greenhouse gas emissions, but its transformation of Earth’s surface by clearing forests, irrigating deserts, and building cities.

• Ocean currents -- global temperature variations over the past century-and-a- half and particularly the past 30 years were due to the slow-down of the ocean’s Thermohaline Circulation (THC).

• Planetary motion -- natural gravitational and magnetic oscillations of the solar system induced by the planet’s movement through space drive climate change.

• Solar variability -- changes in the brightness of the sun cause changes in cloud formation, ocean currents, and wind that cause climate to change.