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Roger Caffin says:
From the paper Dan quoted:
"Meanwhile, we now find that the meso-sphere, between 50 and 90 kilometres up, has been cooling by as much as a degree every year for the past 30 years--ten times faster than anyone had predicted."
"What has caused alarm is the realisation that the cooling of the stratosphere over the past five years has been greater than predicted, especially over the polar regions in winter."
"That the mesosphere is getting colder is not unexpected; like the stratosphere it should be subject to cooling as the troposphere warms. It is the size of this cooling that has taken everyone by surprise."
I have no doubt that we are experiencing global climate change: we are seeing the effects of that here in Australia and also in Europe. (Yes, I understand the difference between weather and climate.)
However, I have yet to be convinced that we understand what is changing, or how or why it is changing, and I have even stronger doubts over whether we really know enough about the physics of the planet to be able to make predictions for the year 2100. The models, any and all of them, are only as good as the data and the physics we put into them. We keep finding new factors.
Cheers
Spot on. The alarmism inherent in the piece quoted implies that the changes in the outer reaches of the atmosphere are due to the increase in the airborne fraction of co2 allegedly due to human emissions. Nothing could be further from the truth. There was a rash of breathless news items form CNN et al at the time. Meanwhile NASA says:
http://www.nasa.gov/topics/earth/features/coolingthermosphere.html
Quiet Sun Means Cooling of Earth's Upper Atmosphere 12.17.09
New measurements from a NASA satellite show a dramatic cooling in the upper atmosphere that correlates with the declining phase of the current solar cycle. For the first time, researchers can show a timely link between the Sun and the climate of Earth’s thermosphere, the region above 100 km, an essential step in making accurate predictions of climate change in the high atmosphere.
Earth's thermosphere and mesosphere have been the least explored regions of the atmosphere. The NASA Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) mission was developed to explore the Earth’s atmosphere above 60 km altitude and was launched in December 2001. One of four instruments on the TIMED mission, the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, was specifically designed to measure the energy budget of the mesosphere and lower thermosphere. The SABER dataset now covers eight years of data and has already provided some basic insight into the heat budget of the thermosphere on a variety of timescales.
The extent of current solar minimum conditions has created a unique situation for recent SABER datasets, explains Stan Solomon, acting director of the High Altitude Observatory, National Center for Atmospheric Research in Boulder, Colo. The end of solar cycle 23 has offered an opportunity to study the radiative cooling in the thermosphere under exceptionally quiescent conditions.
"The Sun is in a very unusual period," said Marty Mlynczak, SABER associate principal investigator and senior research scientist at NASA Langley. "The Earth’s thermosphere is responding remarkably — up to an order of magnitude decrease in infrared emission/radiative cooling by some molecules."
The TIMED measurements show a decrease in the amount of ultraviolet radiation emitted by the Sun. In addition, the amount of infrared radiation emitted from the upper atmosphere by nitric oxide molecules has decreased by nearly a factor of 10 since early 2002. These observations imply that the upper atmosphere has cooled substantially since then. The research team expects the atmosphere to heat up again as solar activity starts to pick up in the next year.
While this warming has no implications for climate change in the troposphere, a fundamental prediction of climate change theory is that the upper atmosphere will cool in response to increasing carbon dioxide. As the atmosphere cools the density will decrease, which ultimately may impact satellite operations through decreased drag over time.
"A fundamental prediction of climate change theory is that upper atmosphere will cool in response to greenhouse gases in the troposphere," says Mlynczak. "Scientists need to validate that theory. This climate record of the upper atmosphere is our first chance to have the other side of the equation."
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