Met Office concedes the error

Over the last day or so, Julia Slingo has sent a polite, but somewhat evasive response to Nic Lewis regarding his critique of the UKCP09 model. It can be seen here.

Nic Lewis's reaction is here. I don't think he is very impressed. The key exchange relates to the following paragraph in Slingo's paper:

Having said that, it is true that the relationship between historical aerosol forcing and equilibrium climate sensitivity (ECS) depicted in your Figure B1 is based only on the PPE. But we disagree with your assertion that the results from HadCM3 are fundamentally biased. It is certainly the case that versions of HadCM3 with low climate sensitivity and strongly negative aerosol forcing are incompatible with the broad range of observational constraints. But the key point is that the relationship between aerosol forcing and ECS is an emergent property of the detailed physical processes sampled in the PPE simulations.

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Spiegel on the IPCC's dilemma

In an article published in its English language edition today, Der Spiegel covers the IPCC's dilemma over the pause - very much the same ground I dealt with in my Spectator blog the other day.

Data shows global temperatures aren't rising the way climate scientists have predicted. Now the Intergovernmental Panel on Climate Change faces a problem: publicize these findings and encourage skeptics -- or hush up the figures.

Not waving but drowning

Updated on Sep 23, 2013 by Bishop Hill

A couple of journalists seem to have shown some interest in Nic Lewis's critique about the UKCP09 climate projections. This may explain why the Met Office has suddenly issued a response a week after Nic's report came out:

Today an article by the GWPF think-tank looks at one element of this – the UK’s official climate projections, known as UKCP09, which were produced by the Met Office.

It claims the Met Office climate model used to make those projections, HadCM3, contains an error and that, because of this error, the projections overestimate warming. The GWPF’s article, however, accepts that the claims of an error have not been substantiated.

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Climate's great dilemma

I have an article up at the Spectator's Coffee House blog on that awful dilemma for the IPCC:

It will not be an easy task. However the IPCC chooses to deal with the problem the repercussions are unpleasant. They might try to explain away the warming hiatus in some way: the in-vogue explanation is that the heat that should have been in the atmosphere has escaped, undetected, to the deep oceans. Evidence to support this idea is, however, scant at best, and going down this route is going to involve the IPCC admitting that there is much about the climate system that is not yet understood. This will be a hard act to carry off while simultaneously claiming that they are certain that mankind caused most of the recent warming.

The Climate Model and the Public Purse

In the kerfuffle over the Mail on Sunday's spread on climate change last week, the panel looking at the problem in the Met Office climate predictions got sidelined somewhat. But the implications of the error are potentially very expensive.

This is the conclusion of a new briefing paper I've put together for GWPF, entitled The Climate Model and the Public Purse. It outlines the nature of the problem and then looks at where the UK climate projections are being used.

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Robbins in the minefield

I've been very nice about Martin Robbins from time to time - I do think he writes some interesting stuff, and he looks at things from interesting angles occasionally too. His blind spot on climate change has always been a bit of a mystery to me.

His article in Vice (which sounds dodgy, but appears to be safe enough) seems to throw some light on the reasons, suggesting that he really only has the most superficial understanding of the subject. For example, he pulls out the NOAA temperature graph and berates us dissenters for pointing out the post-millennial pause, the one that the IPCC is struggling to explain. "But look at the pre-millennium temperature rise" he seems to say. "What a bunch of cherrypickers you bad people are!"

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Dear old George

Dear old George Monbiot has reentered the climate fray - I somehow missed this at the start of the week. It seems like an eternity since he last graced us with his presence, but readers looking for amusement will be pleased to hear that his gratingly sanctimonious style has altered not a bit in the interim.

George's ire has been piqued by the temerity of David Davies, the Tory MP who led the motion against the Climate Change Act in the House of Commons last week. George, in common with the Labour MPs who spoke that day, spends a lot of time ranting about conspiracy theorists, while signally avoiding the fact that the only people who ever mention conspiracies are those, like him, who are obsessed with the idea of fossil-fuel-funded denialist devil-men (Or is green lizards controlling our brains? It's hard to keep up sometimes).

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McKitrick explains the models

Ross McKitrick has a must-read article in the Financial Post, looking at climate models and their environmentalist-like divergence from reality:

The IPCC must take everybody for fools. Its own graph shows that observed temperatures are not within the uncertainty range of projections; they have fallen below the bottom of the entire span. Nor do models simulate surface warming trends accurately; instead they grossly exaggerate them. (Nor do they match them on regional scales, where the fit is typically no better than random numbers.)

A response to the CSAs

Michael Kelly has a letter in the Times responding to the Chief Scientific Advisers' call to trust the IPCC.

Sir, In any form of exact science or engineering, having a discrepancy of a factor of two between theory and experiment would be a source of grave embarrassment. This is not so with climate science where the climate models have overestimated the effect of increasing CO2 on the temperature of the earth’s atmosphere by a factor of two over the past 25 years.

For this reason, the divergence between the predictions of theoretical models and real-world data is growing. If the forthcoming fifth assessment report does not address this problem and its implications in an open and candid manner, the validity of the report will be widely questioned.

Kapow.

Another climate splash in the Mail on Sunday

David Rose has a big splash in the Mail on Sunday, covering a leaked version of the Summary for Policymakers, Nic Lewis's report on the Met Office model and taking a well-aimed potshot at Bob Ward to boot.

They recognise the global warming ‘pause’ first reported by The Mail on Sunday last year is real – and concede that their computer models did not predict it. But they cannot explain why world average temperatures have not shown any statistically significant increase since 1997.

Update on Sep 15, 2013 by Bishop Hill

The Met Office has issued a holding response to the Mail article. Significantly, no mention is made of Nic Lewis's criticisms of their model.

+++Harris and Lewis+++

Nic Lewis has published a detailed comment on the Met Office’s report on climate sensitivity, which was itself very much a response to the Otto et al paper of which Nic was an author. The comment is here.

There is a great deal of interest, not least of which is the fact that the Met Office seems to have made a series of misrepresentations of Otto et al, as well as making several mistakes.

One of these though is astonishing.

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Please, please, believe

With the Science and Technology Committee currently, and with a slight air of desperation, trying to work out a way to persuade the public that the IPCC is trustworthy, it's amusing to see government Chief Scientific Adviser Sir Mark Walport and his three illustrious (and not so illustrious) predecessors writing to the Times today, apparently with the same aim. The article is paywalled, but it's mostly just a recitation of the AGW mantra, with much mention of the empty "consensus".

This is the bit where they explain why we should be getting worried:

It is widely expected that the panel’s fifth assessment report on the physical science basis of climate change, which will be published later this month, will present even greater confidence in the evidence that the climate is warming as a result of human activities.

And therein lies the problem. The models have failed, utterly, completely and catastrophically to predict the halt in temperature rises. That we should then be expected to accept "even greater confidence" about conclusions drawn from them is risible nonsense. This kind of spin is exactly the kind of thing one has come to expect from government chief scientific advisers and the climate establishment and is precisely why people are distrustful of their public utterances.

Garden shed tinkerers

There is a fascinating layman's intoduction to climate models over at Ars Technica. Author Scott Johnson starts out with the standard potshot at global warming dissenters, takes a look at how a GCM is put together and talks to lots of climate modellers about their work and all the testing they do; it has something of the air of a puff piece about it, but that's not to say that it's not interesting.

Here's now it opens:

Talk to someone who rejects the conclusions of climate science and you’ll likely hear some variation of the following: “That’s all based on models, and you can make a model say anything you want.” Often, they'll suggest the models don't even have a solid foundation of data to work with—garbage in, garbage out, as the old programming adage goes. But how many of us (anywhere on the opinion spectrum) really know enough about what goes into a climate model to judge what comes out?

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Lewis on Walport and the HadGem model

In response to yesterday's post about Mark Walport's slide on climate projections, Nic Lewis sends some thoughts about the underlying model - HadGEM2-ES - and its projections of warming to 2100. Click on graphs for full size.

The Walport chart shows warming projections to 2100 from HadGEM2-ES, the Met Office's flagship climate model, used for policy advice (http://www.metoffice.gov.uk/climate-change/policy-relevant/advance).

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A small win for Svensmark

Anthony reports on a new paper by Henrik Svensmark and colleagues, which provides support for his theory that galactic cosmic rays, influenced by the behaviour of the sun, can change the amount of cloud in the sky.

One of the critiques of the Svensmark hypothesis has been that once a cosmic ray has caused an initial chemical reaction between sulphur dioxide molecule and water, the tiny sulphuric acid droplet formed would be too small to seed cloud formation. But in Svensmark's latest experimental replication of conditions in the atmosphere such droplets continued to grow even after the initial reaction. It seems that there is another chemical reaction going on as well, although quite what this is is a mystery at the moment.

I'm not sure it's confirmation of Svensmark's theory, as Anthony's headline suggests, but it's certainly not a problem for it.