CERN’s CLOUD experiment has found two ways to explain how aerosols form in our atmosphere.

Aerosol CERN experiment may explain aerosols

Aerosols are tiny solid or liquid particles suspended in the air. They are a key factor in climate change; they can reflect sunlight and help seed clouds, both of which add a cooling effect to the planet. Until now, we haven’t been able to explain where aerosols come from, but CERN’s CLOUD experiment may have changed that.

In a paper published today in the journal Nature, CERN’s researchers present two breakthroughs that come as a result of the experiment and may explain how aerosols form. The first discovery is that amine vapors, when combined with sulfuric acid can form aerosols in roughly the same rate as we see in the atmosphere. Amines are vapors closely related to ammonia and emanate from natural sources, animal husbandry as well as human activities. The link between aerosols and amines comes as a surprise to the research team.

The other discovery was made with a pion beam from the CERN Proton Synchrotron and demonstrated that ionizing radiation, such as from cosmic rays, has a negligible effect on aerosol formation.

chamber CERN experiment may explain aerosols

The CLOUD team

“Thanks to CERN’s expertise in materials, gas systems and ultra-high vacuum technologies,” explains CERN spokesperson Jasper Kirkby, “we were able to build a chamber with unprecedented cleanliness, allowing us to simulate the atmosphere and introduce minute amounts of various atmospheric vapors under carefully controlled conditions – in this case amines and sulfuric acid.”
The experiment marks the first time atmospheric particles have been formed in an experiment with all interacting components known.