When you look at the whole AGW case, it nearly all rests on the last 40-50 years of ‘recent proxy’ temperature readings, and the human release of CO2 over the ‘industrial revolution’.

Well, the industrial revolution really only got going from about 1800 onward, and CO2 levels had only risen to about 310ppm by 1950.

Temperatures started continuously rising from a trough in about 1650, which is roughly 200 years *before* CO2 levels started a more rapid rise around 1850. Warming was happening anyway, and its (non-CO2) contribution (noise) to the observed rise is never discussed in the AGW story.

The Holocene has been remarkably stable (compared with previous interglacials) with a 0.5 degree C cooling trend over the last 8000 years, and the Wikipedia averaged chart shows approx nine (9) peak-trough temperature swings in the amplitude range of about 0.4 degC. All of which is natural background ‘noise’. Some of these swings ended human civilizations - something on which Ian Plimer and Andrew Glikson agree.

Hence a logical proposition is to run your climate change models backwards with reasonably well known input data (the historical record) and see how accurately they duplicate the known temperature proxies. If the backwards correlations were accurate, then we could have much higher confidence that the background ‘noise’ of natural climate forcings was being correctly modelled, and crucially; that any industrially released CO2 and other GHG effects could be separated out.

Consider the logical absurdity that climate models run very poor correlations backwards with known historical data, yet are trumpeted by AGW theorists as reliable predictors of the future where the input factors going forward are increasingly unknown or just plainly unknowable 40-50 years hence.

Never has the rate of CO2 released from fossil fuel burning and land use been higher than in the last 10 years, yet global temperatures are flat or slightly falling.

What AGW theorists rarely discuss is the role CO2 plays in cooling mechanisms which have peaked and reversed the last 3 interglacials. Icemelt/ocean albedo and re-freezing feedbacks are stated to be the most important mechanisms. Andrew Glikson has stated that the Earth’s atmosphere/ocean system is sensitive to even minor forcings and temperature changes of 0.2 to 0.4 deg C have ended civilizations. All of which happened without human release of ‘industrial’ scale CO2 at all!

The exact role CO2 plays when the system is cooling is still vague. In the case of Prof Karoly’s ‘Swindle’ debate, his CO2 played an incoherent game of ocean absorption/release /feedback/warming - always warming, with icemelt/ocean albedo thrown in to boot! The exact scale of absorption of CO2 by the world’s oceans is largely unknown.

Last week ‘The Economist’ Science & Technology section (23May09) reported that jelly fish like thaliaceans (a type of gelatinous chordate) are one third carbon by weight and in their billions could sink *twice* as much carbon to the ocean bottom as dead planktonic algae; hitherto assumed to be the main way sinking carbon to the ocean bottom. “The carbon cycle has thus acquired another epicycle - something that will have to be added to computer models of how the climate works”.

Without reasonable confidence in the current climate models (gained by accurate backward correlations), who could reasonably argue that CO2 is a major forcing, when Dr Glikson’s ‘minor’ forcings (all natural factors) have caused major climate change in the historical record?

The Antarctica story is critical. AGW theorists have recently found ‘continental’ warming, when respected scientists on the spot find a 30 year cooling trend, and increased East Antarctic ice outweighing lost West Antractic ice. East Antarctica is 4 times bigger than West Antarctica. At 90% of the Earth’s ice, Antarctica is the big knob on the Earth’s thermostat - vastly bigger than all the other global glaciers, ice sheets and the Arctic combined.

A vast climate change edifice is therefore based on 30-40 years of data, with the last 10 years being discounted as a ‘weather anomaly’ by AGW theorists.

Much of the edifice has been based on James Hansen’s NASA/GISS construction of the data. Given the Earth’s vast history of natural climate change, sometimes abrupt and disruptive; a logical thinker would conclude that a lot more than 30-40 years of data is needed to verify the CO2 driven warming theory.

Sceptics such as Ian Plimer produce a raft of arguments to show that the Earth has a history of ‘climate change’ - sometimes rapid and disruptive and subject to a range of natural forcings - some of which we know well and other factors which are poorly known and others which we probably have not yet discovered. None have anything to do with industrial release of CO2.

Instead of remembering the ‘Easter Islanders’ we should remember Dr Paul Ehrlich of 70’s fame, who was a hero of youth worldwide in predicting a “Club of Rome’ food disaster by the end of the 1980’s. Young, sideburned, charismatically bright, Ehrlich held the world in thrall to his prophesies of doom. Opponents such as Dr Colin Clark were pilloried as silly old farts, hopelessly out of touch.

Dr Erhlich was proved wrong, wrong and wrong, and had the good grace to admit it. James Hansen beware.

What you are failing to acknowledge is that the scepticism you’re on about is about the cogency of the so-called scientific evidence-based arguments.

Whether or not the climate science is on the ball, which , frankly I doubt, the general public perception of science and scientists is that of distrust.

Perhaps its because economics, which has tried (really hard) to make itself out as some kind of scientific discipline instead of the social ‘science’ that it actually is, has failed so utterly and dismally at delivering the goods that it promised that it has lowered the tone for the whole scientific neighbourhood. And lets face it, science has promised a lot too..

And if this climate-change mess we’re in is actually human-induced, that means that some boffins somewhere missed something and messed up big time. And now they’re going to fix it? I doubt it, somehow. Climate patterns exist amidst so many variables. Mainstream science can’t even properly explain how the sun works. Add it up mate -

I understand. After all who wants to “believe” in bad news, even if they are manifest in nature as well as in physics and chemistry. But while individual denial may have its place, collective denial of facts and evidence by societies is dangerous.

Rember the Easter Islanders?

I do have to reprove your equation of my “unless …. we have already reached a tipping point…” with glibly saying “it’s safe unless it isn’t”. What I was saying was that, unless we had already reached a tipping point (a suggestion made I think by the ancient mammal expert Tim Flannery), in which case there was ex hypothesi nothing we could do about the runaway disaster that was already under way, there was nothing to suggest that the increases, even the doublings, of CO2 in the atmosphere would have more than marginal effects on the radiative forcing.

Interesting that you call CO2 an “industrial pollutant” (better than Senator Wong’s “Carbon Pollution” solecism I acknowledge). Is that like calling Bougainvillea a weed when it grows up a fence where you don’t want it? However, I accept your point that dumping large quantities of anything into the atmosphere which has a known capacity to react or interact with other ingredients should entail watchfulness at least. Doubling the proportion of oxygen in the atmosphere would presumably have disturbing effects in a biosphere evolved for the accustomed levels of oxygen. Certainly bushfires would be fiercer. So, indeed, let’s pay close attention to what might follow from such large scale emissions.

The problem for a rational Australian is that there doesn’t seem to be much that we can do even if Dr William Kininmonth is wrong in predicting only a 0.5 to 1 degree rise in global temperature’s over the next 50 years or so. (I assume that no one is going to get too fussed about that prospect if it doesn’t go much further because Singpore’s and Helsinki’s annual average temperatures are over 20 degrees apart and both are highly prosperous and livable cities).

Preaching and example perhaps? The sounds of pig wings in take off mode (but never levitating) are to be heard whenever Australians talk in fantasy mode about the rulers of billions of poor people being influenced by anything we do or say (apart from adding to the stock of useful technology). There are, however, things we can do to keep on making ourselves richer and more able to fund research, adaptation of Australia to climate change, and help for those elsewhere who suffer from climate change. Making as much money as we can out of coal and iron ore are indispensable parts of that unless one is a fatuously innumerate and economically illiterate new lefty (posing as a Green which is a bit insulting to those of us who have been planting thousands of trees for decades) who hypes Green jobs and investments in renewables as if they aren’t part of becoming poorer that some of our governments have already started to subsidise with our taxes. It will be great if science and technology crack the big renewable and near-renewable problems. Wind will only be an expensive source of electricity compared with hydrocarbons for the foreseeable future. Solar is a marvellous prospect for Australia but still has a long way to go in conversion of solar energy to electricity and then we need very much better batteries. Nuclear needs the left to see sense and may one day be fusion power……. But, in the meantime, money has a time value and putting on a hair shirt today isn’t going to help anyone much.

While “Search me” is a perfectly acceptable academic position, as I have said the idea that climate change is an academic pursuit is a social strategy of groups who do not want to accept that practical decisions are being made. Whatever side of the argument you are on, it is absolutely certain that what we decide now will determine CO2 levels for a century or more (based purely on the half-life of the gas). A skeptical position academically is fine, therefore, but opposition to action on climate change is a postive committment to higher CO2 levels.

I believe there is a prima facie case that dumping a couple of billion tonnes of a gas into the atmosphere is likely to do something. Its not a little action, doubling the concetration of something in ambient air, and I find the cavalier attitude of people to doing so disturbing. Leaving that aside, however, the answer as to “Why isn’t life an endless task of justifying how much of everything might safely be added to everything else?” is that there is no other industrial pollutant you could get away with doubling the concentration of in the ambient air without any evidence it is not harmful. S0 even if you take the, in my opinion plainly obtuse view that climate change science is so wrong that there is actually nothing at all to worry about, then you are against what would be a usual standard of care for any other chemical.

As for the radiative forcing. In the words of Dr McCoy, “I’m a doctor not a physicist”, but I suspect it is too simple. The fact that the radiative forcing from Co2 is logarithmic is not debated, but you still end up with a positive energy balance and the effects of that are debated. Decreasing marginal effect does not equal no net effect over time.

The caveat that 800 ppm this is safe “unless by some unhappy chance we have already reached a tipping point for runaway global warming because of feedback” is a bit glib, since it amounts to “its safe unless it insn’t”. The feedback mechanisms are a big reason why why people think this level is unsustainable.

But, as I say, this is about practical issues and the reason I ask skeptics what level of CO2 they are happy with is that a ‘business as usual’ approach still gives you 800ppm inside a century. So even if you believe a level that high is safe, and that requires current scientific consensus to be completely and utterly wrong not just a few tweaks on the models, then you still require action in the very near future. Pick virtually any Co2 level ever seen in you will still have to be investing in massive changes to the economy this century and, given the scale of the tast, that would require rapid action. That is what the debate is about - what do we do either by action or inaction. Its not an academic exercise, since no-one is skeptical in their actions.

My scepticism is mainly about the contribution of human released CO2 to global air and ocean temperature observations and its ‘badness’ for the biosphere. If you were to follow the arguments of Crikey regular contributor Andrew Glikson, then you would expect to turn the CO2 knob to 450ppm and get 1 degree warmer, 550ppm and get 2 degrees warmer, etc. I would suggest that the way the Earth handles human released CO2 is much more complex, probably highly non-linear, and very inadequately dealt with by current climate models.

If you look at Charts of the last 3 interglacials, and the roughly 100000 year intervals between, you might even conclude that the next ice age is closer than the start of the Holocene, and that any warming contributed by human released CO2 might be delaying the start of the next glaciation.

On the question of how much atmospheric CO2 might be acceptable, or, more relevantly, how much CO2 by fossil fuel burning can be safely produced and added to the atmosphere it is perhaps scientifically permissible (if not correct) to say that it is an amount that we haven’t got anywhere near yet unless there is a model with convincing and frightening calculations of feedback effects including much better modeling of clouds, evaporation and precipitation than has yet been generally accorded acceptance. Why is that? Because, to quote Dr William Kininmonth “The IPCC have come to the conclusion that 3.7 W/m2 is the ‘forcing’ from a doubling of CO2. The 2.8 W/m2 comes from using the MODTRANS radiation transfer model for clear sky and the US Standard Atmosphere temperature and humidity profile” and the consequence of the 2.8 figure is that, after an absorption of 19.2 W/m^2 of incremental radiation by the first 50 ppm of CO2 in the atmosphere, doubling of the CO2 in the atmosphere thereafter up to 800 ppm and beyond only adds 2.8 W/m^2 radiative forcing for each doubling. It would follow from this that, unless by some unhappy chance we have already reached a tipping point for runaway global warming because of feedback (which never seems to have occurred in the past when temperatures have been high), we are already at a level of atmospheric CO2 concentration beyond which the addtional radiative forcing will be negligible. But that must be too simple mustn’t it? So, would someone please say, in detail, what is wrong with it.

Well at least the evidence is on your side regarding stock tips.

But although it is interesting to hear why you doubt climate change, why you are skeptical etc the question was what you think we need to do about CO2 if anything. What is the counter proposal?

Its like intelligent design. Its not a positively sustainable position because it doesn’t tell you anything predictive about how biology works, its just an anti-position which is created to debate evolution.

So if climate change is wrong, what is the counter theory which informs a skeptics opinion about how much Co2 should be in the air? Because your apparant comfort with “uncharted waters” isn’t really very comforting to the rest of us.

You see I resent being punished for something outside of my control. The debate has gone scalar and is now about the size of my carbon footprint (SOMCF) as though it would be better if I curled up and died quietly somewhere. If other energy forms have been known since Tesler or even Archimedes; e.g. geothermal, zero-point, hydrogen, and more recently cold fusion; not to mention the powers of nature, then why has there been no significant development in any of these clean energy solutions over the 20th century? Why are all the scientists fighting each other over a dubious Al Gorethm when there is so much of the debate which is in no way contentious? The reason I believe that we have stagnated for 100 years (a massive travesty of science) is not a lack of scientific interest, but something to do with the dollars tied up in a continuation of BIG OIL & GAS and BIG COAL.

Whether carbon dioxide is heating the atmosphere or not, we are killing the planet with pollution and the ongoing destruction of our rainforests and oceans.
About this, there is surely no debate. Instead of arguing about instituting a new tax on us, the long suffering patsy public, we should be arguing about the criminal assault on the world’s ecosystems by conscienceless corporate no-accounts and their dictator lackeys. They, in my view, should be held to account and appropriately sanctioned.

Nearly two years ago, I attended a ‘climate change’ seminar presented by a senior ‘scientist’ employed by Rio Tinto. The audience was a university assembly of over 100 professional engineers and academics. The Rio man Powerpointed the ‘hockey stick’, said the ‘debate was over’ and proceeded to show that all of the resources of clean coal, all renewables, nuclear etc would be required to stabilize CO2 levels by 2050. A huge task.

At the end of the seminar, two emeritus Professors of Engineering stood up and vigorously disputed that the ‘debate’ was over, and directly challenged the ‘science’ behind the hockey stick and CO2 driven warming theory. A subdued and shocked Rio man paid his respects to the eminences and the meeting ended in an overflow of repressed doubt expressed by many participants.

My point is that industy (particularly the coal industry) will make a dollar out of any situation, and will go along with the prevailing orthodoxy, particularly when ‘rent seeking’ opportunities are available, and a march can be stolen on the opposition in being ahead of the wave on the ‘next big thing’.

The point to be doubtful of is this:

Even IF human activity is the overarching driver of the changes in climate trends we are being told are occuring, can human intervention serve to ‘reverse’ those changes?

The >>scale<>complexity<< of climate dynamics would strongly suggest not, in which case mitigation efforts should focus on coping, e.g. investing limited and valuable capital in efficiency and effect amelioration rather than unproven, untested, speculative global “solutions to causes” based on shonky Hollywoodesque premises.

See my post above. When the coal industry admits that their emissions are changing the climate, the battle is over. Everything else is so much obfuscation.

Some say that higher CO2 levels will enhance plant growth, increase water vapour in the atmosphere and produce higher crop yields. Others say the opposite. Has climate change affected human civilizations dramatically in the past - you bet it has. And it was all done by natural forcings - not industrial release of CO2.

The reason I have taken a sceptical view, was initially prompted by the ‘shoe shine boy’ effect.

You know the story - when your Yankee shoe shine boy is offering you stock tips - it is time to get out of the market! Well, when pimply youths and fervent schoolchildren start lecturing their elders about the calamities to come from ‘climate change’ - then its time to take a hard look at the evidence and the observations.

What I found was an uncritical acceptance and alarmism by public commentators, academics and the media, that climate change was novel and inherently bad.

I am indebted to Dr Chris Schoneveld (WE Australian Feb 2008) for this elegant proof of the falsity of this premise: Quote;

“One only has to take about 50 things humans like (butterflies, cave paintings, wine, peace, health) and 50 things we don’t like (sharks, feral cats, jellyfish, allergies, crime, drought, floods) and perform a Google search for each in combination with the term ‘global warming or climate change’ and the following will emerge: anything we like will be negatively affected and anything we don’t like will benefit. For example, you will never find butterflies thriving and cockroaches suffering.

Since the forces of nature are insensitive to the preferences of humans, one would expect a balanced outcome of thriving or declining likes and dislikes. Since this is not the case, the statistical significance of this exercise allows us to draw the conclusion that the science of climate change is alarmist and subject to severe bias.” End Quote

Try this yourself, and reach the same conclusion.

I therefore invite all those on the ‘nay’ side of the climate change debate to answer one simple question. Using whatever means you feel appropriate, what is the ‘safe’ level of carbon dioxide in the atmosphere?

I ask this because it is irrefutable tha CO2 is increasing year on year and, without the sort of measures most people feel are justified by climate change, it will keep on increasing. So where do the ‘skeptics’ feel we should draw the line. Is any amount of CO2 OK? 500ppm, 800pp, 2000ppm?

I am interested in the positive assertions of those who do not believe in APW, beacuse I generally just here what they think is NOT happening. What is it that you people think IS happening.

When you look at the whole AGW case. it nearly all rests on the last 40-50 years of ‘recent proxy’ temperature readings (often quoted in the NH only), and the human release of CO2 over the ‘industrial revolution’.

Well, the industrial revolution really only got going from about 1800 onward, and CO2 levels had only risen to about 310ppm by 1950.

Temperatures started continuously rising from a trough in about 1650, which is roughly 200 years *before* CO2 levels started a more rapid rise around 1850. Warming was happening anyway, and its (non-CO2) contribution (noise) to the observed rise is never discussed in the AGW story.

The Holocene has been remarkably stable (compared with previous interglacials) with a 0.5 degree C cooling trend over the last 8000 years, and the Wikipedia averaged chart shows approx nine (9) peak-trough temperature swings in the amplitude range of about 0.4 degC. All of which is background ‘noise’.

Hence a logical proposition is to run your climate change models backwards with reasonably well known input data (the historical record) and see how accurate they duplicate the known temperature proxies. If the backwards correlations were accurate, then we could have much higher confidence that the background ‘noise’ of natural climate forcings was being accurately modelled, and crucially that the CO2 and other GHG effects could be separated out.

Consider the logical absurdity that climate models run very poor correlations backwards with known historical data, yet are trumpeted by AGW theorists as reliable predictors of the future where the input factors going forward are increasingly unknown or just plain unknown !

Never has the rate of CO2 released from fossil fuel burning and land use been higher than in the last 10 years, yet global temperatures are flat or slightly falling.

What AGW theorists rarely discuss is the role CO2 plays in cooling mechanisms which have peaked and reversed the last 3 interglacials. Icemelt/ocean albedo and re-freezing feedbacks are stated to be the most important mechanisms. Andrew Glikson has stated that the Earth’s atmosphere/ocean system is sensitive to even minor forcings and temperature changes of 0.2 to 0.4 deg C have ended civilizations. All of which happened without human release of ‘industrial’ scale CO2 at all!

The exact role CO2 plays when the system is cooling is still vague. In the case of Prof Karoly’s ‘Swindle’ debate, his CO2 played an incoherent game of ocean absorption/release /feedback/warming - always warming, with icemelt/ocean albedo thrown in to boot!

Without reasonable confidence in the climate models (gained by accurate backward correlations), who could reasonably argue that CO2 is a major forcing, when Glikson’s ‘minor’ forcings (all natural factors) have caused major climate change in the historical record?

A vast climate change edifice is therefore based on 30-40 years of data, with the last 10 years being discounted as a ‘weather anomaly’ by AGW theorists.

Much of the edifice has been based on James Hansen’s Nasa/GISS construction of the data. A reasonable person would conclude that a lot more than 30-40 years of data is needed to verify the CO2 driven warming theory.

Tha Antarctica story is critical. AGW theorists have recently found ‘continental’ warming, when others find a 30 year cooling trend, and increased East Antarctic ice out-weighing lost West Antractic ice. At 90% of the Earth’s ice, Antarctica is the big game in town vastly outweighing all the other global glaciers, ice sheets and the Arctic.

A whole lot more is going on here.

Just on that subject, I strongly recommend subscribers read Professor Ian Plimer’s heaven+earth for it is by far the best text I have read demolishing the arguments of zealots who push the global warming cart. Plimer’s text includes an excellent chart of the changes in global warming/cooling over the last 1000 years, a chart I had seen quite some years ago. Today’s fluctuations are far from abnormal! Greenland was actually green farmland in the late single digit centuries, the world didn’t come to an end, and the world wasn’t industrialised. He also plots several well regarded measures of global temperatures, showing them falling since 1998. He discusses the early formation of the United Nations IPCC and the political forces behind it. Great election winner! Arnie Schwarzenegger showed that in California, and Rudd kicked off his first debate with John Howard - “Are you a climate change skeptic,” as if to answer in the affirmative was to acknowledge worship of the devil incarnate as against simply being a rational man, evaluating a critical issue that could be costly to the nation indeed.

This rather pious assertion is incorrect given the role of sociological and political debate about scientific issues in the modern world. When vested interests are threatenied, and by this I mean the undeniable commercial interests of the corporate sector and politicians they support (sorry, lobby) rather than an imagined intellectual club of scientists, then they respond with a synthesised debate.

This is because their PR men have learned a simple cycle of denial. First you keep it from public recognition (the 1950s to 1980s), then you ridicule it (the 1990s) and when all else fails you call for a frank and open debate. This debate is not about the evidence, its about managing the social environment to avoid a response. This works precisely because, to the deliberately obtuse, a debate can go on forever. The record of the evidence linking smoking to cancer is instructive. Debate started when conclusive evidence became available not when no-one had a clue, because when no-one had a clue there was no need to debate.

The Australian Coal industry, those with most to lose, have admitted that CO2 emissions from coal is driving climate change.

http://www.newgencoal.com.au/

Go on, harp on about it just being a sales pitch or what ever, like anyone has a choice about buying coal anyway. It’s over. The only debate left to have is how to respond. I disagree that doubt is sensible and intelligent in this case. To put it another way, from the comfort of home, and by reading second/third hand reports, you think you know better than the combined knowledge of the UN and NASA. That despite the summits, conferences and regulations, you’re pretty sure that you know better. Do you not see a flaw in that?

This nonsense about collusion, grants, blah blah blah, it’s all obfuscation and nonsense. This has become a politically awkward issue; surely any/every Government in the world would make it go away if it wasn’t true. So go on, continue bickering, but remember that for most of us, we’ve stopped listening, it’s all over.

I would like models to be tested for the ability to retro-predict the major climatic changes of the past that produced 1. The wiping out of the Egyptian Old Kingdom and drying up of the Sahara; 2. Wiping out of the early Indus civilisation; 3. Drying up of the Great Lakes in North America. All of these occurred well after the end of the last major Ice Age.

I raise these and the silence is always profound. David Karoly did in a very general way say Nos. 1 and 3 were all within the explanatory envelope of the IPCC models but, with no chance to cross-examine, I remain questioning.

Will someone proffer a serious response out of the AGW corner? Without it all being ultimately disappointing or flawed links for preference.