Cloud formation on Earth may be linked to cosmic rays

August 29, 2011 – SWITZERLAND – It sounds like a conspiracy theory: ‘cosmic rays’ from deep space might be creating clouds in Earth’s atmosphere and changing the climate. Yet an experiment at CERN, Europe’s high-energy physics laboratory near Geneva, Switzerland, is finding tentative evidence for just that. The findings, published today in Nature1, are preliminary, but they are stoking a long-running argument over the role of radiation from distant stars in altering the climate. For a century, scientists have known that charged particles from space constantly bombard Earth. Known as cosmic rays, the particles are mostly protons blasted out of supernovae. As the protons crash through the planet’s atmosphere, they can ionize volatile compounds, causing them to condense into airborne droplets, or aerosols. Clouds might then build up around the droplets. The number of cosmic rays that reach Earth depends on the Sun. When the Sun is emitting lots of radiation, its magnetic field shields the planet from cosmic rays. During periods of low solar activity, more cosmic rays reach Earth. Scientists agree on these basic facts, but there is far less agreement on whether cosmic rays can have a large role in cloud formation and climate change. Since the late 1990s, some have suggested that when high solar activity lowers levels of cosmic rays, that in turn reduces cloud cover and warms the planet. Others say that there is no statistical evidence for such an effect. “People are far too polarized, and in my opinion there are huge, important areas where our understanding is poor at the moment,” says Jasper Kirkby, a physicist at CERN. In particular, he says, little controlled research has been done on exactly what effect cosmic rays can have on atmospheric chemistry. –Nature News

CERN: Sun causes climate change shock 

Reference chapter: It came from outer Space in my book and Mike thanks for following the book and contributing the news story. Science is following us.