Atmospheric water vapour is a feedback (not forcing) - on Watts and Eschenbach #AGU16 poster

Willis Eschenbach has a poster at AGU16, to which Anthony Watts added his name. Anthony's now written a blog article about it (archived here). Actually, Anthony put his name first although I strongly suspect he doesn't have a clue what the poster is all about.

They haven't made the poster available on the AGU16 website, or not at the time of this article. It is downloadable on Anthony's blog at WUWT, here.  He's also made available what he calls "data and code". The file is 500 MB or so, therefore I won't be downloading it till I get home in 20 hours or so.

There are a few points I'll make:

• The poster is based on a couple of blog articles by Willis Eschenbach at WUWT, including the one I wrote about here.
• Willis Eschenbach still doesn't know the difference between a forcing and a feedback (more below). Nor does Anthony Watts.
• Their poster supports what real scientists tell us, that there's more water vapour in the air because of global warming.
• Most of the data they use is ocean only, not land.
• They seem happy to rely on RSS data, while disparaging it elsewhere.
• They seem happy with lots of data carefully collected and analysed by climate scientists, despite calling it fraudulent elsewhere, and despite WUWT-ers wanting to stop all research.

Leland Park has discovered seasons, day and night at WUWT

After various mundane articles about politics, sea level rise, and tips for deniers on how to reduce the scariness of global warming, there was another rather silly and simplistic article, this time by Leland Park (archived here). It would have been sweet, worthy of an eight-year-old's science essay, except that he mixed up cause and effect and didn't understand most of what he wrote. Worse still, at the bottom of his guest essay he wrote:

The negative feedback between solar levels and temperatures has always existed – but never noticed, officially. I, for one, will be interested to learn how quickly climate science can adapt CO2 theory to explain away its implications.

This is what Leland Park thinks was never noticed officially:

• The hottest time of the year is after, not on, the solstice
• The hottest time of the day is after, not at, noon.

Leland thinking he discovered this would astound even Dunning and Kruger. That Anthony Watts decided to publish his article won't astound anyone much.

Putting the foot to the floor - with Willis Eschenbach again

Yesterday I wrote about how Willis Eschenbach, a frequent contributor at Anthony Watts' denier blog WUWT, got his feedbacks and forcings all mixed up. I've been thinking more about where he went wrong. Willis used an analogy of a car with cruise control.

The external forces acting on the car are gravity and friction. Willis didn't mention those forces. The cruise control can kick in to oppose changes in these forces by introducing an opposing force of the engine. It can add fuel to increase or decrease the engine power, apply brakes to oppose the engine, and shift gears to increase or decrease the power of the engine. It will do this when it detects a change in speed. The change in speed trigger will only come about when there is a change in forcing.

On forcing and feedback with Willis Eschenbach

For a long time now (at least six years), Willis Eschenbach has been going on about governors, forcing and feedback. For a long time now (at least six years), the engineers at WUWT have been pointing out where Willis gets his terminology and concepts wrong. For a long time now, Willis hasn't listened to the experts.

Willis Eschenbach maintains, despite all evidence to the contrary, that climate doesn't change. He seems to think that every time a forcing is applied, it will be met with an equal and opposite force. Today he's arguing the same thing that he's argued time and time again.

As in the past, Willis gets quite a bit wrong (archived here):

• uses the analogy of cruise control (wrongly)
• confuses positive and negative feedback
• mistakes feedback for forcing.

This article is about some fundamental concepts in climate science, mainly for the benefit of people new to the subject. (You'd think deniers at WUWT, who've been writing about climate for years, would have grasped these concepts by now. But many of them, like Willis Eschenbach, haven't.)