McIntyre on models and obs

Prof Willem de Lange recommended Steve McIntyre’s analysis of Dr Christy’s iconic graph and Richard C (NZ) asked me to repost it, so here it is. I think it’s another example of patient, objective endeavour overcoming zealotry. Please let me know if you see it differently and let me know if you agree, but see something I missed. It’s an immense pleasure to put this before you. – RT

Gavin Schmidt and Reference Period “Trickery”

— by Steve McIntyre, Climate Audit – Apr 19, 2016


This is an adopted article.

In the past few weeks, I’ve been re-examining the long-standing dispute over the discrepancy between models and observations in the tropical troposphere. My interest was prompted in part by Gavin Schmidt’s recent attack on a graphic used by John Christy in numerous presentations (see recent discussion here by Judy Curry). Schmidt made the sort of offensive allegations that he makes far too often: Continue Reading →

If even one climate model was accurate we wouldn’t need another

On the Helix Facebook page yesterday, Richard Betts writes about High-End Climate Impacts and Extremes.

He claims “the chances are that global warming will exceed the 2°C “guardrail” that the EU and UN aim to stay below,” and doesn’t disagree with alarmist interpretations of the scale and effects of man-made global warming, such as the possibility of 6°C warming. But “science” says little about our future climate. Continue Reading →

Lawrence Solomon mocks models

via Lawrence Solomon: Model mockery | Financial Post.

Top economist, a true believer in global warming, proves predictions of catastrophe are meaningless

All predictions of global warming doom and destruction rest on meaningless computer models, say climate change skeptics such as Freeman Dyson, America’s best known scientist, and Antonino Zichichi, Italy’s best known scientist. They and other skeptics looked at models touted as reliable and declared them meaningless.

Now these unabashed skeptics are joined by an unabashed true believer in rising sea levels, greater climate variability and other perils associated with global warming: Robert S. Pindyck, a physicist, engineer and Professor of Economics and Finance at MIT’s Sloan School of Management. Continue Reading →

Signs of strain in justifying climate predictions

Professor Michael Kelly, Prince Philip Professor of Technology, University of Cambridge, kindly sends us his comments on a letter this month to Nature Geoscience, Test of a decadal climate forecast, by Myles R. Allen, John F.B. Mitchell and Peter A. Stott. I previously commented on the letter in Climate forecasts fulfilled or what? Mike just returned to England after spending seven months as Visiting Professor at the prestigious MacDiarmid Institute, Victoria University of Wellington.

The recent paper of Allen et al. does a careful job of estimating errors in forward projections of global temperatures from earlier calculations on global circulation models of the atmosphere. Given the simple question — are the models doing a good job or not — the increasing level of sophistication needed to defend them is of concern. For many of us, a temperature stasis of 17 years is enough to suggest that the models are not as robust as some of their advocates maintain. Continue Reading →

Harder and harder to ignore

Professor Myles Allen -- will you ignore him?

Bishop Hill has an account — Lindzen at the Oxford Union — of the recent Oxford debate involving (mainly) Professors Richard Lindzen and Myles Allen. The latter comments (1.25pm):

“I was deeply embarrassed to be associated with Hasan’s ad hominem attacks on Dick Lindzen, in particular his going on about speaker fees and airline tickets. I thought this was going to be a discussion of climate science, and most of it seemed to be, as ever, about people and politics. As I hope I made clear when I had the chance, these were completely irrelevant to the discussion (and nothing he brought up seemed in any way exceptionable anyway) and that kind of attempt at personalising everything is just what is preventing a sensible discussion. I am very sorry that a visitor to Oxford was treated in this way.

On the science side, I’m happy to accept that studies comparing simple models with observations of the recent record, of which several have been published recently, suggest a climate sensitivity in the region of 2 degrees (although this isn’t the only line of evidence). But even a two degree sensitivity, if we do decide to burn all available fossil carbon, which would take concentrations well over 1000ppm, would be more than enough for 4+ degrees of warming. The real question, therefore, is whether 4+ degrees is OK. That’s what we need to be discussing, and unfortunately, because once again it was side-tracked onto irrelevancies, the debate didn’t go there.” (emphasis added)

Continue Reading →

Antarctic ice expands “against odds”

From a scientist friend, who comments:

About two weeks after it was noised on various blogs and electronic news sources, and is old “news”, The Australian finally deigns to notice the record Antarctic sea-ice (I wonder whether the SMH and The Age will now me-too the story as well?). Leaving aside the wonderful headline, the article itself is a classic attempt to weasel out of accepting the obvious conclusion. The scientists involved really ARE shameless.

I entirely agree with him. This story presents a deplorable mish-mash of propaganda from a scientist who should be a lot better behaved. Be nice to see this covered in the Herald – or has it been – anyone know?

Please note the frank distortion in the original headline: the sea ice hasn’t expanded “against the odds”, it has simply defied certain (wrong!) predictions. Emphasis added, my comments in green. – RT

PAYWALLED AT: The Australian.

* by: Graham Lloyd
* From: The Australian
* October 06, 2012 12:00AM

ANTARCTIC sea ice has expanded to cover the largest area recorded since satellite mapping began more than three decades ago, in stark contrast to this year’s record melt on the northern pole.

The expansion continues a trend of increasing Antarctic sea ice cover of about 1 per cent a decade and is at odds with predictions of climate change models that continue to forecast a long-term decline. Continue Reading →

Imagine — a computer predicts our demise just as…

… our demise occurs!

Here’s an argument against the validity of climate catastrophe, straight out of the “too good to be true” basket. It goes something like this:

“After several centuries of humanity’s meandering technological development, the odds are remote that, at precisely the time of our demise, we developed computer hardware and models sophisticated enough to predict our imminent demise.”

Computers are now sophisticated enough to model our demise but not so sophisticated that they know more than we do. The likelihood of our demise actually being imminent is vanishingly small because:

  1. We don’t know how the climate works.
  2. There’s been no warming since 1995, despite a 20% increase in CO2.
  3. The atmosphere (since 2001) and the ocean (since 2004) have been cooling.
  4. Models fail hindcasts, thus inspiring no confidence in their forecasts.
  5. The IPCC, from whom the government takes its advice, is utterly discredited.
  6. There’s been no alteration in natural rates of sea-level change.
  7. We don’t know how the climate works.

But don’t believe me – ask any climate scientist (warmist or sceptic) and they’ll tell you we don’t know how the climate works.

h/t – GJB

More learned about water — science still not settled

Scientists have long debated the impact on global climate of water evaporated from vegetation. New research from Carnegie’s Global Ecology department concludes that evaporated water helps cool the earth as a whole, not just the local area of evaporation, demonstrating that evaporation of water from trees and lakes could have a cooling effect on the entire atmosphere. These findings, published on 14 September in Environmental Research Letters, have major implications for land-use decision making.

The researchers even thought it was possible that evaporation could have a warming effect on global climate, because water vapour acts as a greenhouse gas in the atmosphere.

Using a climate model, they found that increased evaporation actually had an overall cooling effect on the global climate. Continue Reading →

Computer model is not evidence

NZ Herald crest

Letter sent to the Herald on 7 Jan, 2011
quill pen

Dear Sir,

It has come to my attention that you published a (further) letter from a Dr Doug Campbell, again challenging Professor Chris de Freitas’ recent article about the science of global warming. Dr Campbell said: “The facts support anthropogenic global warming with a doubling of atmospheric carbon dioxide resulting in warming of between 2 °C and 4.5 °C.”

I wish to point out that, as a matter of fact, that is not a fact.

Dr de Freitas was talking about an expected temperature increase from carbon dioxide alone of about 1 °C, and he mentioned that was, “by itself, relatively small” and “not controversial.”

Dr Campbell, if he disagrees with that, should cite his authority for doing so. The only source of temperature increases greater than one degree is various computer climate models. These models give different results on each run. Continue Reading →

NASA study on CO2 warming finds cooling effect

UN climate conferences obsolete

New study considers vegetation cooling

A new NASA computer modelling effort has found that the additional growth of plants and trees in a world with doubled atmospheric carbon dioxide levels would create a new negative feedback — a cooling effect — on the Earth’s climate system that could work to reduce future global warming to only +1.64°C if carbon dioxide was doubled. The IPCC had assumed a +3°C warming in that case.

The cooling effect would be -0.3 degrees Celsius globally and -0.6 degrees C over land, compared to simulations where the feedback was not included, said Lahouari Bounoua, of Goddard Space Flight Center, Greenbelt, Md. Bounoua is lead author on the paper that was published Dec 7, 2010, in the journal Geophysical Research Letters.

With the negative feedback included, the model found a warming of 1.64 degrees C globally when carbon dioxide was doubled.

Doubling the CO2 contents in the atmosphere from 390 ppmv to 780 ppmv would require some 195 years with the present growth rate of 2 ppm/year. This means, however, that until the year 2100 we have to expect a temperature increase of only 0.75°C. Also, with the higher IPCC value, the resulting temperature growth would be well below the limit of 2°C which has been decided as a limit by the recent conference in Cancun.

Apparently none of the 15,000 participants in Cancun has recognized this fact (or, rather, did not want to do so) since this means that the political UN conference-circus is indeed obsolete. No new post-Kyoto agreement is required, nor a reduction of CO2 emissions at all.

However, we must expect that the expensive annual mega-meetings will continue, since no participant wants to give up these free vacation weeks in one of the more beautiful places of this planet (Kyoto – Bali – Nairobi – Rio de Janeiro – Geneva – New Delhi – Marrakesh – Buenos Aires – Copenhagen – Cancun – and next year Durban, South Africa).

The most important decision at each of 16 conferences was to meet again next year. And if it were only for that reason, then the “fight against climate change” must be continued.

sourced from the Climate Sceptics group in Yahoo Groups

DomPost asks our opinion

It’s always nice to be asked for our opinion, and especially so when it’s for public consumption. The friendly Kiran Chug (yes, that’s her surname, lovely person) gave the Climate Conversation Group a mention yesterday in her article Kiwi aids climate-change research overhaul.

Here’s a portion, quoting Martin Manning:

The goal was to come up with a “better approach in the future” which better co-ordinated research from different scientific areas and made it more useful to policy makers, he said.

“This is not about admitting that anything that has been done in the past is wrong.”

However, Richard Treadgold, from the Climate Conversation Group, said the scientists’ group was pre-empting its findings by assuming its research would need to be acted on by policymakers.

A climate change sceptic, he did not accept that models predicting the future could be evidence of climate change.

“Evidence is from the real world, that’s been observed. There’s no way computer models fulfil those requirements.”

Wellington scientist and climate change sceptic Vincent Gray said the researchers were continually coming up with “new models” but they were still “fiddling the figures” and were unlikely to restore public confidence in their work until their projections were proven.