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The stratosphere has been cooling for 30 years!

Started by drowe, 05/28/2009 09:06PM
Posted 05/28/2009 09:06PM Opening Post


That's the TLS satellite channel (lower stratosphere) from RSS http://ssmi.com/msu/msu_data_description.html#msu_amsu_trend_map_tls )

But why aren't the skeptics all over this?

Two reasons -
1) Its a predicted result of warming by greenhouse gasses
2) If you're banking on changes in solar output to explain recent increases in the surface temperature, you really don't want to have the stratosphere cooling on you.

The why is simple - the theory that increasing GH gasses will cause global warming depends on the fact that GH gasses trap infra red radiation being radiated from the earth surface - more GH gasses means more IR being absorbed hence increased temperatures.

But that means that the lower atmosphere, with its greater gas concentration and closer proximity to the earth's surface, will absorb more IR radiation from the earth's surface so that less IR makes it to the upper atmosphere (the stratosphere). Decrease the IR reaching the stratosphere and it's going to cool.

Which is what AGW theory predicts - a warming lower atmosphere and a cooling stratosphere.

FWIW - here's what the RSS satellite data (from the same link above) show for the lower atmosphere:



However, if you're betting that increases in the suns output has caused recent warming, then you would want to see the upper atmosphere warming - after all, solar radiation hits the stratosphere before the lower atmosphere and the earth's surface so how could this supposed extra solar radiation pass through the stratosphere and cause the lower atmosphere to warm and yet not warm the stratosphere but actually cause it to cool?

Hmmm - maybe that's why skeptics don't like to talk about the cooling stratosphere?
Posted 05/29/2009 02:22PM #1
Very interesting. I haven't heard of this. Please keep us informed on this theory.

I don't doubt the data at all and it comes from a reliable source. I'm just waiting for someone to prove a correlation between CO2 data and atmospheric temperature for anything other than 1980-1998.

http://ff.org/centers/csspp/library/co2weekly/2005-08-18/dioxide_files/image002.gif
Posted 05/29/2009 06:14PM #2
Couple of interesting points on the TLS plots:

About those two warm spikes: Satellite measurements of the lower stratosphere (TLS) reveal two marked warm periods (as much as 1.5oC warmer), caused by sulfuric acid aerosols deposited in this layer by the eruptions of El Chichón in 1982 and Pinatubo in 1991.

On the negative trend: These two warm periods are concurrent with a strong cooling trend over the 19-year period that has been attributed to ozone depletion in the lower stratosphere... The TLS channel shows a negative trend, and along with the ozone depletion factor, indicates that we aren’t getting much heat transport from the troposphere into the stratosphere.

The trend looks flat for the last 15 years. Is that from ozone control, solar activity, no greenhouse change, or is it just too short a period to draw any conclusions from?
Posted 05/29/2009 06:18PM #3
Not to "cherry-pick" the data too much, but the graph shows no cooling of the stratosphere over the last 15 years. Similarly, lower level heating is practically level over the same period. Isn't this when most of the "hockey-stick" increase in CO2 has been taking place?

"Praise the Lord for the expanding grandeur of creation, worlds known and unknown, galaxies beyond galaxies, filling us with awe and challenging our imaginations." 2007 Reform Siddur