Cosmic raise in cloud

January 19, 2006

New evidence that events in outer space affect the weather and climate of Earth has been revealed in a study by meteorologists at the University of Reading published in the Proceedings of the Royal Society on Wednesday 18 January.

In their paper ‘Empirical evidence for a non-linear effect of galactic cosmic rays on clouds’, Drs Giles Harrison and David Stephenson suggest that cosmic rays have a significant effect on the Earth’s lower atmosphere – particularly on levels of cloudiness.

The Reading meteorologists discovered that the chance of an overcast day decreases by 20% on days with low cosmic ray fluxes. The effect is strongest when low cosmic ray fluxes occur – this is often associated with solar flares, but may also result from changes outside the solar system.

“Back in 1959, Edward Ney suggested that variations in cosmic rays, which are charged particles mostly originating outside the solar system, could affect our weather,” said Dr Harrison. “This research now provides strong evidence supporting Ney’s suggestion, which effectively links atmospheric and space science.”

“As well as the influence of weather, our evidence shows a small yet statistically significant effect of cosmic rays on daily cloudiness. This suggests that cosmic rays are an additional external source of climate variability that should be considered when modelling past and future climate.”

To detect changes in the atmosphere from cosmic rays, Harrison and Stephenson used solar radiation measurements made by meteorological stations. They conducted a careful analysis of the UK archives of daily solar radiation observations from 1951-2004 and compared them with neutron counter cosmic ray measurements taken at Climax, Colorado, between 1951 and 2000.

In 1927, the British physicist C.T.R. Wilson received the Nobel Prize for the cloud chamber, which he invented to simulate atmospheric cloud processes. The cloud chamber makes cosmic rays visible by condensing water droplets on ions produced by the cosmic rays. Wilson developed the cloud chamber in the 1890s to simulate atmospheric cloud production processes. He initially thought that ions provided all the nuclei in the atmosphere for cloud formation, but subsequently discovered that clouds formed on uncharged particles too. The mechanism suggested by Harrison and Stephenson to explain the effect of cosmic rays on clouds found is different to Wilson's, and depends on the particles formed by ions, rather than the action of the ions themselves. This is an important distinction, as the cloud chamber does not reproduce real atmospheric conditions. Wilson's work was also published in the Proceedings of the Royal Society.

Cosmic rays were discovered by Viktor Hess, following a high altitude balloon flight in August 1912. Hess received the Nobel prize for the discovery in 1936.

Source: University of Reading

Explore further: Chandra data suggest giant collision triggered 'radio phoenix'

Related Stories

The mystery of Jupiter's Great Red Spot

August 5, 2015

The largest and most powerful hurricanes ever recorded on Earth spanned over 1,000 miles across with winds gusting up to around 200 mph. That's wide enough to stretch across nearly all U.S. states east of Texas. But even ...

Celebrating a year at the comet

August 6, 2015

It's been a long but exciting journey for Rosetta since its launch in 2004, featuring Earth, Mars and two asteroid flybys before arriving at its ultimate destination on 6 August 2014. Over the following months, the mission ...

Recommended for you

Quantifying the impact of volcanic eruptions on climate

August 31, 2015

Large volcanic eruptions inject considerable amounts of sulphur in the stratosphere which, once converted into aerosols, block sun rays and tend to cool the surface of the Earth down for several years. An international team ...

Researchers unveil DNA-guided 3-D printing of human tissue

August 31, 2015

A UCSF-led team has developed a technique to build tiny models of human tissues, called organoids, more precisely than ever before using a process that turns human cells into a biological equivalent of LEGO bricks. These ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.