Back in 1979, Russell Schnell of the University of Colorado was in western Kenya wondering why the tea plantations there held the world record for hailstorms. They occurred 132 days a year. He discovered that tiny particles of dead and decaying leaves in the soil bore a close resemblance to the tiny particles around which hailstones formed. They were, it turned out, far better adapted to the task even than man-made cloud seeding chemicals like silver iodide.
Schnell, who is now deputy director of the Global Monitoring Division of the National Oceanic and Atmospheric Administration, concluded that “the feet of hundreds of tea pickers going about their daily jobs” were to blame for the hail. By kicking the bits of leaf into the air, he said, the tea pickers must be providing the abundant ice-nucleators that created the hailstorms. He published in Tellus in 1982, revealing that the critical actors in this Kenyan drama were the bacteria, Pseudomonas syringae, that attached hemselves to the leaves as they rotted — the tea pickers sent the leaf bits airborne as they walked the fields picking the tea leaves from the bushes.
“Bioprecipitation” is a hot topic. And the more so as we learn how much biological matter there is in the atmosphere — more than 10,000 individual bacteria per cubic meter of air over the land, according to a 2009 study by Susannah Burrows of the Max Planck Institute for Chemistry in Mainz, Germany. These bacteria spend an average of about a week in the atmosphere; but while some stay close to the ground, others soar into the stratosphere, says Smith. Weather balloons have even found them in the mesosphere, up to 77 kilometers aloft, according to a forgotten study by Soviet scientist A. A. Imshenetsky, published in Applied and Environmental Biology as long ago as 1978 and uncovered by Smith.
This, says Dale Griffin of the U.S. Geological Survey in Tallahassee, Florida raises another interesting possibility. “Does the Earth shed microbial life into space, and how would this impact on our quest for extraterrestrial life? There are all kinds of interesting questions in this field, and very few people dabbling in it.”
It looks as if bugs in the air may not just be key players in local weather and disease. Scientists are now growing interested in the possibility that bugs in the air may influence global climate.
- More Here
Schnell, who is now deputy director of the Global Monitoring Division of the National Oceanic and Atmospheric Administration, concluded that “the feet of hundreds of tea pickers going about their daily jobs” were to blame for the hail. By kicking the bits of leaf into the air, he said, the tea pickers must be providing the abundant ice-nucleators that created the hailstorms. He published in Tellus in 1982, revealing that the critical actors in this Kenyan drama were the bacteria, Pseudomonas syringae, that attached hemselves to the leaves as they rotted — the tea pickers sent the leaf bits airborne as they walked the fields picking the tea leaves from the bushes.
“Bioprecipitation” is a hot topic. And the more so as we learn how much biological matter there is in the atmosphere — more than 10,000 individual bacteria per cubic meter of air over the land, according to a 2009 study by Susannah Burrows of the Max Planck Institute for Chemistry in Mainz, Germany. These bacteria spend an average of about a week in the atmosphere; but while some stay close to the ground, others soar into the stratosphere, says Smith. Weather balloons have even found them in the mesosphere, up to 77 kilometers aloft, according to a forgotten study by Soviet scientist A. A. Imshenetsky, published in Applied and Environmental Biology as long ago as 1978 and uncovered by Smith.
This, says Dale Griffin of the U.S. Geological Survey in Tallahassee, Florida raises another interesting possibility. “Does the Earth shed microbial life into space, and how would this impact on our quest for extraterrestrial life? There are all kinds of interesting questions in this field, and very few people dabbling in it.”
It looks as if bugs in the air may not just be key players in local weather and disease. Scientists are now growing interested in the possibility that bugs in the air may influence global climate.
- More Here
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