Where’s Bart Verheggen when I need him?
In Matt Ridley’s recent essay published by the GWPF, he says he needs to have 10 questions answered before he will think that policies to address global warming make any sense. I have tried to address his first two questions here and here. Matt was kind enough to leave some comments on my second response.
The third issue he needs answered is, “Nor am I convinced that sulphate aerosols and ocean heat uptake can explain the gap between model predictions and actual observations over the last 34 years. Both are now well understood and provide insufficient excuse for such an underperformance. Negative cloud feedback, leading to total feedbacks being modest, is the more plausible explanation.”
The role of aerosols is a matter of debate in climate science. They block the sun. They can contribute to cloud formation . Many scientists are convinced that they mask global warming and that if we actually got rid of them, warming would increase.
Skeptics have often expressed the opinion that some climate modelers use aerosols as a ‘plug’ in their models to help them hindcast past temperatures. Modelers vigorously dispute this characterization as a slur on their integrity.
And we are in way over my head. I don’t know how to answer Mr. Ridley’s point. I haven’t studied this in any depth, nor have I seen plain English explanations that make me nod my head in vigorous agreement or shake it in equally vigorous opposition.
So I hereby ask for your help and am making this a dedicated thread to discussion of aerosols and whether or not there is a sufficient body of evidence to present to Mr. Ridley as an answer to his question.
(As for global ocean heat uptake, I think we’re all just hanging around and waiting for enough Argos observations to make some definitive points either way. There’s sufficient blustering on both sides of the issue for anyone to pick an argument that suits–but we just need those buoys to keep rising, falling and measuring a little longer. Feel free to pitch in on this one, too.)
‘Bout time I made you all do the heavy lifting, anyhoo. I got a Super Bowl to get ready for.
Update: As the conversation is getting a bit heated, let’s reset the terms. I really would like this to be a place where those on either side of the fence can have a civil–almost friendly–discussion. That requires effort on both sides of the ball (why am I using a sports metaphor? …oh, yeah, that’s why…)
Please provide answers to the following questions and discuss in a civil manner:
1. Is Matt Ridley correct to be concerned about this issue? Is this a ‘deal-breaker’ for climate science and its former conclusions of .2C per decade for the early part of this century?
2. Is the volume of aerosols adequate to produce the effects claimed for it?
3. Are some of the properties of aerosols producing more than one climatic effect (e.g., blocking sun and lowering heating, nucleating clouds with unknown effects, etc.)?
4. Is the treatment of aerosols in the literature proportionate to their real or potential effect(s)? Are they, for example, handled appropriately in AR4 (or AR5 if anyone has read the relevant sections in the leaked draft)?
5. Are estimates of aerosols treated appropriately in the employment of GCMs?
I really want your opinion on these issues. I am really not interested in your negative opinions of others on this thread–especially as some of you who are fussin’ and feudin’ are really good people who just are both commenting and reading too quickly.
I speak as someone who often commented in such a fashion in the past. It got me nowhere in the conversation–I know what I’m talking about regarding commenting.