SSS 2010-05-28(在线收听

This is Scientific America's Sixty-Second-Science. I am Steve Mirsky. Got a minute?

Some interesting electrical activity in the clouds of ash drifting around Europe as a result of that Icelandic volcano. Models predicted that electrical charge should be limited to the top and bottom of any ash plume, which is often the site of spectacular lightning.

But info obtained by a weather balloon found significant electrical charge within the plume. And that such charge was being generated within the plume—it wasn’t a remnant of the energy of the volcanic eruption or a result of any local weather events. Interactions among ash particles seem to be constantly renewing the charge.

The finding appears in the journal Environmental Research Letters and is the first peer-reviewed research related to the April volcano eruption.

The study authors note that charging can change the way the particles clump and how they interact with rain. The practical reason for understanding the electrical nature of ash plumes is that they can interfere with aircraft radio communication. And if any charged ash infiltrates a plane, it could be an electrostatic hazard, to the plane’s systems and to the plane’s passengers.

Thanks for the minute for Scientific America's Sixty-Second-Science. I am Steve Mirsky.
 

  原文地址:http://www.tingroom.com/lesson/sasss/2010/5/101827.html