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gigantikok: and here's just a little more information for you guys:
Support Grows for Sun-Climate Link
A striking correlation has been found between changes in the sun’s brightness and changes in global temperatures. One of the problems with any explanation that attributes climate changes to changes in the sun’s energy output is that the output is not large enough by itself to account for change on earth. Several theories have been advanced to explain how changes in the sun can translate into large climate changes on earth.
The New Scientist (July 11, 1998) discusses the recent work of Eigil Friis-Christensen and Knud Lassen of the Danish Meteorological Institute. Their theory says energetic particles from space known as cosmic rays assist in cloud formation. The more clouds, the cooler the earth becomes. Solar winds, according to Friis-Christensen and Lassen, block cosmic rays leading to less cloud cover and a warmer planet.
The article advances two other theories about the correlation between solar activity and climate change. Joaana Haigh, a physicist at Imperial College, London, believes that fluctuations of ultraviolet radiation are the culprit. UV radiation fluctuates three times as much as total radiation throughout a solar cycle. At the point during the solar cycle where UV radiation peaks there is a 2 percent jump in stratospheric ozone levels, raising stratospheric temperatures by 0.5 degrees C. This causes the stratosphere to sink, pushing the hot tropical weather toward the middle latitudes, causing global warming.
Niel Arnold and Terry Robinson, physicists at the University of Leicester, believe that the thermosphere, the earth’s outer atmosphere becomes heated by absorbing both ultraviolet and X-rays from the sun. Fluctuations in the sun’s output could double the temperature of the thermosphere. This warming effect can be carried to lower altitudes speeding up the jet stream by up to 20 percent, changing stratospheric temperatures by several degrees, say the researchers. So far these theories have only been tested using computer models. Empirical tests for some of these theories are being considered.
Support Grows for Sun-Climate Link
A striking correlation has been found between changes in the sun’s brightness and changes in global temperatures. One of the problems with any explanation that attributes climate changes to changes in the sun’s energy output is that the output is not large enough by itself to account for change on earth. Several theories have been advanced to explain how changes in the sun can translate into large climate changes on earth.
The New Scientist (July 11, 1998) discusses the recent work of Eigil Friis-Christensen and Knud Lassen of the Danish Meteorological Institute. Their theory says energetic particles from space known as cosmic rays assist in cloud formation. The more clouds, the cooler the earth becomes. Solar winds, according to Friis-Christensen and Lassen, block cosmic rays leading to less cloud cover and a warmer planet.
The article advances two other theories about the correlation between solar activity and climate change. Joaana Haigh, a physicist at Imperial College, London, believes that fluctuations of ultraviolet radiation are the culprit. UV radiation fluctuates three times as much as total radiation throughout a solar cycle. At the point during the solar cycle where UV radiation peaks there is a 2 percent jump in stratospheric ozone levels, raising stratospheric temperatures by 0.5 degrees C. This causes the stratosphere to sink, pushing the hot tropical weather toward the middle latitudes, causing global warming.
Niel Arnold and Terry Robinson, physicists at the University of Leicester, believe that the thermosphere, the earth’s outer atmosphere becomes heated by absorbing both ultraviolet and X-rays from the sun. Fluctuations in the sun’s output could double the temperature of the thermosphere. This warming effect can be carried to lower altitudes speeding up the jet stream by up to 20 percent, changing stratospheric temperatures by several degrees, say the researchers. So far these theories have only been tested using computer models. Empirical tests for some of these theories are being considered.