Researchers at the CERN particle physics laboratory in Geneva, Switzerland report new evidence supporting the theory that cosmic rays may increase the sun’s impact on global temperatures and climate.
Cosmic ray theory postulates that increases in solar output not only increase global temperatures through relatively direct heating of the Earth but also indirectly by blocking cosmic rays that spur cloud formation when entering the Earth’s atmosphere. When higher solar activity blocks cosmic rays from reaching the atmosphere, the Earth experiences clearer skies that serve to further warm the planet. Thus, according to cosmic ray theory, the impact of solar variability on global temperatures is higher than scientists previously believed.
Researchers at CERN set up an experiment designed to replicate how cosmic rays might affect cloud formation. The researchers fired varying concentrations of particles from a proton accelerator into a chamber containing ultra-pure air and selected trace gases. They found that in conditions simulating the Earth’s upper atmosphere, cosmic rays can increase the rate of aerosol production (which is key to cloud formation) by a factor of 10 or more.
The results do not necessarily confirm the theory that cosmic ray variance plays a significant role in global temperature fluctuations, but the results do—to the surprise of many cosmic ray theory doubters—invalidate some of the key objections to cosmic ray theory.
James M. Taylor ([email protected]) is managing editor of Environment & Climate News.