soulxtc
September 12th, 2006, 05:33 PM
Weather on Earth has a surprising connection to space weather occurring high in the electrically-charged upper atmosphere, known as the ionosphere, according to new results from NASA satellites. "This discovery will help improve forecasts of turbulence in the ionosphere, which can disrupt radio transmissions and the reception of signals from the Global Positioning System," said Thomas Immel of the University of California, Berkeley, lead author of a paper on the research published August 11 in Geophysical Research Letters.
Researchers discovered that tides of air generated by intense thunderstorm activity over South America, Africa and Southeast Asia were altering the structure of the ionosphere.
The ionosphere is formed by solar X-rays and ultraviolet light, which break apart atoms and molecules in the upper atmosphere, creating a layer of electrically-charged gas known as plasma. The densest part of the ionosphere forms two bands of plasma close to the equator at a height of almost 250 miles. From March 20 to April 20, 2002, sensors on board NASA's Imager for Magnetopause to Aurora Global Exploration (IMAGE) satellite recorded these bands, which glow in ultraviolet light.
Using pictures from IMAGE, the team discovered four pairs of bright regions where the ionosphere was almost twice as dense as the average. Three of the bright pairs were located over tropical rainforests with lots of thunderstorm activity -- the Amazon Basin in South America, the Congo Basin in Africa, and Indonesia. A fourth pair appeared over the Pacific Ocean. Researchers confirmed that the thunderstorms over the three tropical rainforest regions produce tides of air in our atmosphere using a computer simulation developed by the National Center for Atmospheric Research, Boulder, Colo., called the Global Scale Wave Model.
The connection to plasma bands in the ionosphere surprised scientists at first because these tides from the thunderstorms can not affect the ionosphere directly. The gas in the ionosphere is simply too thin. Earth's gravity keeps most of the atmosphere close to the surface. Thunderstorms develop in the lower atmosphere, or troposphere, which extends almost 10 miles above the equator. The gas in the plasma bands is about 10 billion times less dense than in the troposphere. The tide needs to collide with atoms in the atmosphere above to propagate, but the ionosphere where the plasma bands form is so thin, atoms rarely collide there.
http://www.physorg.com/newman/gfx/news/154188main_plasma_bands_lgweb.jpg
http://www.physorg.com/news77293757.html
Researchers discovered that tides of air generated by intense thunderstorm activity over South America, Africa and Southeast Asia were altering the structure of the ionosphere.
The ionosphere is formed by solar X-rays and ultraviolet light, which break apart atoms and molecules in the upper atmosphere, creating a layer of electrically-charged gas known as plasma. The densest part of the ionosphere forms two bands of plasma close to the equator at a height of almost 250 miles. From March 20 to April 20, 2002, sensors on board NASA's Imager for Magnetopause to Aurora Global Exploration (IMAGE) satellite recorded these bands, which glow in ultraviolet light.
Using pictures from IMAGE, the team discovered four pairs of bright regions where the ionosphere was almost twice as dense as the average. Three of the bright pairs were located over tropical rainforests with lots of thunderstorm activity -- the Amazon Basin in South America, the Congo Basin in Africa, and Indonesia. A fourth pair appeared over the Pacific Ocean. Researchers confirmed that the thunderstorms over the three tropical rainforest regions produce tides of air in our atmosphere using a computer simulation developed by the National Center for Atmospheric Research, Boulder, Colo., called the Global Scale Wave Model.
The connection to plasma bands in the ionosphere surprised scientists at first because these tides from the thunderstorms can not affect the ionosphere directly. The gas in the ionosphere is simply too thin. Earth's gravity keeps most of the atmosphere close to the surface. Thunderstorms develop in the lower atmosphere, or troposphere, which extends almost 10 miles above the equator. The gas in the plasma bands is about 10 billion times less dense than in the troposphere. The tide needs to collide with atoms in the atmosphere above to propagate, but the ionosphere where the plasma bands form is so thin, atoms rarely collide there.
http://www.physorg.com/newman/gfx/news/154188main_plasma_bands_lgweb.jpg
http://www.physorg.com/news77293757.html