… and it was fun to see my charts in it! The lecture is reprinted here (pdf) or here (html) over at Anthondy Watts’ site. The charts I did are around pages 6-7 of the pdf, the ones showing the projected curve of global warming for various climate sensitivities, and backing into what that should imply for current warming. In short, even if you don’t think warming in the surface temperature record is exaggerated, there still has not been anywhere near the amount of warming one would expect for the types of higher sensitivities in the IPCC and other climate models. Warming to date, even if not exaggerated and all attributed to man-made and not natural causes, is consistent with far less catastrophic, and more incremental, future warming numbers.
These charts come right out of the IPCC formula for the relationship between CO2 concentrations and warming, a formula first proposed by Michael Mann. I explained these charts in depth around the 10 minute mark of this video, and returned to them to make the point about past warming around the 62 minute mark. This is a shorter video, just three minutes, that covers the same ground. Watching it again, I am struck by how relevant it is as a critique five years later, and by how depressing it is that this critique still has not penetrated mainstream discussion of climate. In fact, I am going to embed it below:
The older slides Ridley uses, which are cleaner (I went back and forth on the best way to portray this stuff) can be found here.
By the way, Ridley wrote an awesome piece for Wired more generally about catastrophism which is very much worth a read.
I read his article in Wired and it was a very good historical summary of all the big scaremongering campains.
I am still witing for someone to put together a TOTAL alternative energy scheme, including standby ans storage, assuming the CAGW idea is correct.
Thanks for reminding us that it is all about feedback. AGW is not the problem it is CAGW and the catastrophe depends upon massive positive feedback which hasn’t been happening.
BTW: Despite huge CO2 discharged during WW2 it cooled from 1940 to 1978 supposedly from aerosols. It there any measurement of aerosols over that time period to the present ?
I just spent 1/2 hour on Google looking for 1940 to present aerosol data and it apparently doesn’t exist so the alarmists can say it was whatever fits their lie.
netdr, you mentioned that it cooled from 1940 to 1976. My reading of the data is that the actual cooling period was from 1945 to 1976. Despite being an alarmist myself, I agree with the suggestions that aerosols were not the primary cause of the cooling.
Steve Challis
Steve
This chart shows cooling from 1940 to 1978 approximately.
http://data.giss.nasa.gov/gistemp/graphs_v3/Fig.A2.gif
Since this period coincides with the negative PDO almost exactly I find it interesting.
During this time we had a world war and tons of CO2 was emitted but it cooled.
Warming didn’t start until the PDO became positive.
I don’t think aerosols had anything to do with it but as I said below there is no historical data available to the public on aerosols so the alarmists claim whatever supports their story best.