Ground-based bacteria may be making it rain
- 12 January 2009 by Devin Powell
- Magazine issue 2690
BACTERIA may be able to make it rain without ever leaving the ground - if the powerful detergents they produce can reach the clouds, that is.
Previous studies have suggested that bacteria can affect cloud formation. For example, an analysis of snow samples has hinted that bacteria swept up into the atmosphere trigger precipitation so that they can return to the ground.
Now Barbara Nozière of Stockholm University, Sweden, and colleagues suggest that surfactants secreted by many species of bacteria could also influence the weather. While these are normally used to transport nutrients through membranes, the team have shown that they also break down the surface tension of water better than any other substance in nature. This led them to suspect that if the detergent was found in clouds it would stimulate the formation of water droplets.
To find out if they were present in the atmosphere, Nozière collected ...