Comments on: More on Climate Feedback

By: Neil Wilkins

Neil Wilkins — Mon, 18 Aug 2008 03:49:35 +0000

It is utterly impossible for the planet to have positive feedback for the warming and CO2 level. All earth scientists know that the earth has a history of much higher CO2 and temperatures than now. If positive feedback was even slightly possible then earth wouldve warmed up and life extinguished at one of many warming events since the time at which the current atmosphere dominated by N and O developed about 2 billion years ago. Before that the earth was dominated by methane CO2 and N and H2O – even more potent greenhouse gases. since the last 2 billion years of our current atmospheric regime there have been many many rises in CO2 yet all were eventually followed by cooling. This is the ultimate proof.
No wonder the very great majority of earth scientists regard climate “scientists” as sad jokes. They are like phrenologists in the 19th century – they dress their own preconcieved beliefs and political agendas up as scientific proofs.

By: Scientist

Scientist — Fri, 28 Mar 2008 21:29:17 +0000

You want paleoclimate evidence? Start by doing a search for 'paleocene-eocene thermal maximum'. But what's wrong with looking at the last century? We can calculate the solar forcing, the aerosol forcing, and the greenhouse gas forcing, and if we don't include the greenhouse gas forcing we cannot explain the temperature pattern. Physics tells us that more CO2=hotter atmosphere; observations verify that.

I criticise your use of the word 'likely' because it is extremely vague and you haven't offered any evidence of why you think CO2 is a minor influence.

By: Industry Insider

Industry Insider — Thu, 27 Mar 2008 23:18:29 +0000

Scientist - Now you're hassling me for saying "likely?" Are you serious?

Maybe I should include a table of probability percentages in my posts like the IPCC uses ("probably" = >50% chance, etc.). Heck, if I go the IPCC route, I could justify my conclusions based on "expert judgement" without any rigorous justification and not get called out on it. That would be fun!

By: Industry Insider

Industry Insider — Thu, 27 Mar 2008 23:12:09 +0000

Scientist - you state "There is indeed statistically significant trend information indicating that CO2 increases cause temperature increases."

Please cite references. Show me the statistically significant proof in the paleoclimate record.

By: Scientist

Scientist — Thu, 27 Mar 2008 21:18:57 +0000

You’ve offered nothing to back your claim that CO2 is only a minor factor and is offset by other factors. It’s pure supposition and extremely vague, as shown by the very hopeful sounding ‘likely’ you threw in there. There is indeed statistically significant trend information indicating that CO2 increases cause temperature increases. I know of no scientist who has managed to explain that pattern of 20th century temperature trends without CO2 concentrations rising.

By: Industry Insider

Industry Insider — Wed, 26 Mar 2008 21:21:43 +0000

**Crunch** (That's the sound of the strawman you just built and then knocked over.)

I never said CO2 cannot induce changes in temperature. CO2 may influence climate, but that influence is likely minor and offset by other factors. If CO2 were the driver of climate change, then there would be statistically significant trend information indicating that CO2 increases cause temperature increases and CO2 decreases cause temperature decreases. This is not the case over the last 500MM years, the last 500k years, or even the last century. Throw out predictions based on the climate models (and discarding them seems appropriate, considering how well the feedbacks in the models have been shown to match reality), and the AGW crowd is left with nothing but a few paleoclimate antecdotes where CO2 and temperature changes coincide.

By: morganovich

morganovich — Wed, 26 Mar 2008 21:18:25 +0000

ahh, the "everyone knows" argument.

show me one conclusive piece of evidence that CO2 was the primary cause/precipitator of a past warming.

By: Scientist

Scientist — Wed, 26 Mar 2008 20:12:21 +0000

It’s very well known that CO2 can induce changes in temperature. No point in me reinventing the wheel. However, if you’ve never heard of the wheel there’s a lot to be said for learning about it. If you genuinely don’t think that CO2 is not a driver of climate change, you’ve got some basic physics revision to do.

By: Industry Insider

Industry Insider — Wed, 26 Mar 2008 19:16:32 +0000

Scientist - the reason: other climate forcings and feedbacks.

The arbitrary point "600MM years ago and 7,000 ppm" just represents a snapshot in time. Over the intervening period, the overall trend has been more solar insolation, and both CO2 concentrations and temperatures have fluctuated significantly without any systematic correspondence between the two variables. There have been periods when CO2 increased but temperature decreased. This would indicate the presence of other forcings that dominated any effect of CO2 during these periods.

As I indicated before, you have a chance to contribute to climate science here. If you can prepare a detailed analysis of paleoclimate temperature, CO2, and insolation; correct/adjust for insolation; and show (in a statistically significant way) that changes in CO2 concentration induce changes in temperature, you will have something worthy of publishing. Otherwise, we can just continue to waste our time trading antecdotes.

By: Scientist

Scientist — Wed, 26 Mar 2008 14:41:28 +0000

Actually Industry Insider, I think that post answers your points as well. Please tell me if you think it doesn't.

If you think CO2 has a minor effect on climate, I wonder what explanation you'd give for why temperatures are not 10°C higher than they were 600 million years ago, given the 14 W/m² increase in solar insolation.