The Earth’s greenhouse effect is due to the fact that some components of the atmosphere (water vapor, CO2, CH4, etc.) are effectively transparent to incoming UV radiation and opaque to certain bandwidths of outgoing IR radiation. This greenhouse effect causes the Earth’s atmosphere to be about 30° C warmer than it would be without greenhouse gases.
If anthropogenic greenhouse gas emissions are warming the planet through an enhanced greenhouse effect, the Stratosphere should cool as the Troposphere warms. At first glance it does look like the Stratosphere has cooled and the Troposphere has warmed a bit over the last 30 years…
But this impression is misleading. Two very large, low-latitude volcanic eruptions caused a very significant warming of the Stratosphere in 1982 (El Chichón, Mexico) and 1991 (Pinatubo, Philippines) and a very powerful El Niño warmed the Troposphere in 1998. These three phenomena caused the appearance of concurrent stratospheric cooling and tropospheric warming in the satellite temperature data.
The problem is that the stratospheric cooling and tropospheric warming have never been simultaneous. I calculated the monthly differences of the stratospheric and tropospheric temperature anomalies from the University of Alabama, Huntsville (UAH) satellite data to get d-Strat and d-L Trop. Then I multiplied d-Strat times d-L Trop. A negative d-Strat * d- L Trop means that d-Strat and d-L Trop are moving in opposite directions and should indicate an increased greenhouse effect. A positive d-Strat * d- L Trop should mean that d-Strat and d-L Trop are moving in the same direction and should indicate a decreased greenhouse effect. If the Stratosphere is cooling due to a progressively increasing retention of heat in the lower atmosphere (enhanced greenhouse effect), d-Strat * d-L Trop should exhibit a measurable negative trend… But it doesn’t…
The slope is actually very slightly positive; which is consistent a very slight decline in total greenhouse warming over the last 30 years. This would mean that negative feedback mechanisms in the atmosphere are offsetting the increasing atmospheric CO2 concentration.
Debunk House 
January 3, 2010 at 14:33 |
Interesting…
I’m not clear on exactly how you did this:
-to calculate d-Strat you calculate the monthly stratosphere temp anomaly from one month minus the monthly stratosphere temp anomaly from the following month, and continue this thru the 30 years?
-do you have a link to the data used?
Thanks
January 4, 2010 at 08:39 |
d-Strat is the UAH stratosphere monthly anomaly minus the previous month’s anomaly.
d-Trop is the UAH lower troposphere monthly anomaly minus the previous month’s anomaly.
I then multiply d-Strat times d-Trop.
If the troposphere warms and stratosphere cools in the same 1-month period, d-Strat * d-Trop will be a negative number. The product will also be negative during months in which the troposphere cools and stratosphere warms. If the stratosphere and troposphere are both cooling or warming, the product will be a positive number.
Hypothetically, an enhanced greenhouse effect should produce a negative bias in the d-Strat * d-Trop series… There should be more months with a negative product than with a positive product. I don’t see that sort of trend. This tells me that the warming of the troposphere from 1979-2009 is not due to an increasing greenhouse effect.
The satellite temperature data can be downloaded from NOAA’s NCDC here: Tropospheric and Stratospheric Temperature Record from Satellite Measurements.
I use the UAH data.