Tag: CO2

New dimensions in earth science uncovered by NZ blogger

Exciting new concepts in earth systems science are emerging from the fertile intellect of one of Hot Topic’s most diligent readers, Ian Wishart. Either that, or he’s demonstrated (again) that he doesn’t understand what he’s writing about. In this astonishing post, published yesterday, he considers something he calls the “feedback warming effect”, and attempts to use a new paper on carbon cycle feedbacks to support Monckton’s nonsense on climate sensitivity.

Just as Chicken Little pontificates about the minutiae of a Monckton allegation about warming amplification being overestimated by six of seven times, along comes a new study in Nature that compared real data with the computer models and found CO2’s feedback warming effect has been exaggerated in the models by five or six times.

Monckton’s TV lies are not mentioned — minutiae to Wishart, obviously — but he then points to this paper: Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate, Frank et al, Nature, 2010; 463 (7280) as if it offers support for Monckton. It doesn’t, as I shall explain, but is Wishart wrong about Monckton, wrong about Frank et al, or both?

 

Monckton’s “paper”, Climate Sensitivity Reconsidered, is about what it says it is — the global temperature response to (by definition) a doubling of CO2 in the atmosphere. Monckton tries, and fails, to show that this response is small — he claims under 1ºC at doubling. Wishart refers to climate sensitivity as “warming amplification”, which — to be charitable — is a terminological inexactitude.

Frank et al, on the other hand, is the latest effort to pin down how much extra CO2 will be released from the various parts of the carbon cycle as global temperature increases, and suggests that it could be smaller than had been expected [Science Daily]. This “extra” CO2 clearly is an amplification of warming caused by human emissions, and it’s good news that this may be smaller than expected. Wishart describes the study thus:

…[it] compared real data with the computer models and found CO2’s feedback warming effect has been exaggerated in the models by five or six times.

What did Frank et al actually do? Physics World describes their method:

… David Frank and colleagues at the Swiss Federal Research Institute in Birmensdorf, the University of Bern and the Gutenberg University in Mainz have performed the most comprehensive analysis of carbon dioxide and temperature data yet. The team studied the period 1050–1800 AD, when manmade emissions were small enough to be ignored. Carbon dioxide levels were determined from three Antarctic ice cores. Average temperatures in the northern hemisphere were derived from nine different “proxy reconstructions” of temperature – average temperatures derived mostly from tree rings and the isotopic content of ice cores.

No comparisons with models, but a lot of use of paleoclimate data — you know, the tree ring stuff you find in those “debunked” hockeystick blades — and ice cores (and in Wishart-world they can’t be trusted, because Wishart relies on the “work” of EG Beck). Frank and his co-workers use this data to try to work out how much extra CO2 is released when the planet warms — and find that instead of the 40 ppmv/ºC found in previous empirical studies, it was more likely to be in the range 2–21 ppmv/°C, with 8 ppmv/°C being the most likely. The BBC asked Frank what this means for model projections of temperature change this century:

He said that if the results his paper were widely accepted, the overall effect on climate projections would be neutral.
“It might lead to a downward mean revision of those (climate) models which already include the carbon cycle, but an upward revision in those which do not include the carbon cycle.
“That’ll probably even itself out to signify no real change in the temperature projections overall,” he said.

Wishart doesn’t seem to have much of a handle on carbon cycle feedbacks and what they mean for model projections, but he’s canny enough to spot that someone might quibble with his penetrating analysis, so he includes this caveat:

A note for the pedants: the Monckton claim and the Nature paper are approaching a similar problem (magnitude of feedback warming) from slightly different directions (Monckton’s comment relates to rise in temp caused by doubling of CO2, whilst the Nature paper examines the increase in CO2 caused by a rise in temperature), but the general thrust of the arguments is similar: extra carbon dioxide is not going to cause as much feedback as previously claimed.

Clear as mud, Ian. This pedant would point out that the problems being considered are not the same and the “general thrust of the arguments” is not at all similar. Monckton isn’t talking about “feedback warming”, he’s talking about warming caused by a fixed increase (by definition a doubling over pre-industrial conditions) in CO2. He wants us to believe that the temperature response to increasing CO2 is tiny. On the other hand, Frank et al’s conclusions are based on linking small changes in global temperature over the period from 1050 to 1800 to small increases and decreases in CO2 levels.

In other words, if Monckton is right, then Frank et al’s methodology can’t work. Far from supporting Monckton, Frank et al add yet more reasons why he has to be wrong. Meanwhile, Wishart is wrong on all counts. I wonder how such an expert climate commentator could have failed to notice? Perhaps he should get his stuff peer reviewed. Where’s Monckton when you need him…?

More than a number

If you want to know what’s happening on a stockmarket, the first place to look is at the relevant index — the Footsie (FTSE) for the London Stock Exchange, or the Dow Jones for Wall Street. Those indices aggregate all the price movements over a day into one handy number, to give a quick overview of how the market’s behaving. Now a group of scientists working for the International Geosphere-Biosphere Programme (IGBP) have compiled a Climate Change Index (CCI) to provide the same service for the evidence of climate change. The CCI was launched in Copenhagen yesterday. The video above describes the approach they’ve used, and the “ladder” graphic below shows how the CCI has moved over the last 30 years:

CCI_steps_bigger.jpg

The CCI tracks changes in global temperature, atmospheric CO2, Arctic sea ice, and sea level. An increase in the CCI shows a move away from a stable climate. Over the last 30 years the cumulative shift has been 574 points — in the wrong direction. The IGBP team point out that the CCI responds to global cooling events such as the Pinatubo and El Chichon eruptions, but they are also looking at adding other indicators to the index including land-use, fisheries exploitation, population, fire and extreme events. They are planning to update the index every year, and to backdate it to periods before 1980.

[The Drifters]

Marvellous distempered: the Copenhagen diagnosis

The Copenhagen climate conference (COP15) opens its doors in a little under two weeks. To update participants on the science of climate a new assessment report, The Copenhagen Diagnosis, was released yesterday, and it makes grim reading. Designed to inform “a target readership of policy-makers, stakeholders, the media and the broader public” about the evidence that’s emerged since the 2005 cut-off for the IPCC’s Fourth Report, it is especially strong on the accumulating signs of climate change as it happens.

Evidence of melting of the Greenland and Antarctic ice sheets supports a revision of the expected sea level rise by the end of the century: it “may well exceed” a metre. The rapid sea ice loss in the Arctic in recent years highlights the risks of methane releases from permafrost, but the most direct message is that with global carbon emissions surging up to and beyond the highest of the IPCC’s scenarios, and with pretty strict limits on the amount of carbon we can add to the atmosphere and stay under a 2ºC rise, we need to start cutting emissions soon.

Here’s what the emissions growth looks like:

CopCO2emissions.jpg

And here’s what we need to do to stay under 2ºC:

CopDiagtargets.jpg

It’s a simple enough message. The longer we leave it before starting to cut emissions, the steeper the cuts will need to be. And there’s an obvious corollary: steep cuts will be more expensive. Inaction now means more cost in the future. Where does that leave any government promising to “balance the economy and the environment”?

Below the fold: the full executive summary.

Continue reading “Marvellous distempered: the Copenhagen diagnosis”

…Some fish, some barrel

I’m afraid he’s at it again. Wishart, that is. It seems he can’t stop himself from reading Hot Topic and then posting his reactions. In his latest excursion, he reads a comment of mine, and then feels the need to once again demonstrate the depth of his understanding. He begins thus:

Can you believe the chutzpah? The thing that gets me about climate Chicken Littles is the way they repeat bogus claims ad nauseum as if true… this comment from Gareth Renowden at Hot Topic tonight illustrates ignorance on this point:

“In deep time, there have been periods when CO2 has been higher than now (how much higher is a matter of study), but lots of CO2 is inevitably associated with a warmer planet.”

Invariably?? The blue line is temperature, the black line is CO2:

And he whips out the chart you see above (click on the thumbnail to be taken to the source). It features (without credit to source) on page 34 of Air Con. He continues:

I defy anyone, including Renowden, to find a pattern in the historical record that proves CO2 is “invariably” associated with a warmer planet. It will be especially hard for him as the ice cores all show CO2 rise lags temperature increase by several hundred years, not precedes it.

I didn’t have to try very hard to defy Wishart, because the “pattern” is well-established in the literature:

Continue reading “…Some fish, some barrel”

Deep time, deep water

The last time CO2 hit a sustained level of 400 ppm 15-20 million years ago global average temperatures were 3 – 6ºC warmer than now, and sea level was 25 to 40 m higher, according to research released last week. That’s bad news, because the target for current international negotiations to find a successor to Kyoto is 450 ppm. The finding also provides support for James Hansen’s view that 350 ppm is the maximum “safe level” for CO2 if we want to inhabit a planet with ice at both poles.

Meanwhile, analysis of the Andrill core has discovered a “remarkably warm” period in Antarctica that occurred abruptly 15.7 million years ago, when the McMurdo Sound region could have had January air temperatures of 10ºC and sea temps up to 11.5ºC, according to a new paper in Geology.

Continue reading “Deep time, deep water”