Take the greenhouse gasbags with a grain of salt
Bjorn Lomborg
October 15, 2008
The Australian

HAVE you noticed how environmental campaigners almost inevitably say that not only is global warming happening and bad, but also that what we are seeing is even worse than expected?

This is odd, because any reasonable understanding of how science proceeds would expect that, as we refine our knowledge, we find that things are sometimes worse and sometimes better than we expected, and that the most likely distribution would be about 50-50. Environmental campaigners, however, almost invariably see it as 100-0.

If we are regularly being surprised in just one direction, if our models get blindsided by an ever-worsening reality, that does not bode well for our scientific approach.

Indeed, one can argue that if the models constantly get something wrong, it is probably because the models are wrong. And if we cannot trust our models, we cannot know what policy action to take if we want to make a difference.

Yet if new facts constantly show us that the consequences of climate change are getting worse and worse, high-minded arguments about the scientific method might not carry much weight. Certainly, this seems to be the prevailing bet in the spin on global warming. It is, again, worse than we thought and, despite our failing models, we will gamble on knowing just what to do: cut CO2 emissions dramatically.

But it is simply not correct that climate data are systematically worse than expected; in many respects, they are spot on, or even better than expected. That we hear otherwise is an indication of the media's addiction to worst-case stories, but that makes a poor foundation for smart policies.

The most obvious point about global warming is that the planet is heating up. It has warmed about 1C over the past century and is predicted by the UN's Intergovernmental Panel on Climate Change to warm between 1.6C and 3.8C this century, mainly owing to increased CO2.

An average of all 38 available standard runs from the IPCC shows that models expect a temperature increase in this decade of about 0.2C.

But this is not at all what we have seen. And this is true for all surface temperature measures and even more so for both satellite measures. Temperatures in this decade have not been worse than expected; in fact, they have not even been increasing. They have actually decreased by between 0.01C and 0.1C a year.

On the most important indicator of global warming, temperature development, we ought to hear that the data are actually much better than expected.

Likewise, and arguably much more significantly, the heat content of the world's oceans has been dropping for the past four years where we have measurements. Whereas energy in terms of temperature can disappear relatively easily from the light atmosphere, it is unclear where the heat from global warming should have gone, and certainly this is again much better than expected.

We hear constantly about how the Arctic sea ice is disappearing faster than expected, and this is true. But most serious scientists also allow that global warming is only part of the explanation. Another part is that the so-called Arctic oscillation of wind patterns over the Arctic Ocean is in a state that it does not allow build-up of old ice but immediately flushes most ice into the North Atlantic.

More important, we rarely hear that the Antarctic sea ice is not only not declining but is above average for the past year. IPCC models would expect declining sea ice in both hemispheres but, whereas the Arctic is doing worse than expected, Antarctica is doing better.

Ironically, the Associated Press, along with many other news outlets, told us in 2007 that the "Arctic is screaming" and that the Northwest Passage was open "for the first time in recorded history". Yet the BBC reported in 2000 that the fabled Northwest Passage was already without ice.

We are constantly inundated with stories of how sea levels will rise, and how one study after another finds that it will be much worse than what the IPCC predicts. But most models find results within the IPCC range of a sea-level increase of 18cm to 59cm this century. This is, of course, why the thousands of IPCC scientists projected that range. Yet studies claiming 1m or more obviously make for better headlines.

Since 1992, we have had satellites measuring the rise in global sea levels and they have shown a stable increase of 3.2mm a year: spot on compared with the IPCC projection. Moreover, over the past two years, sea levels have not increased at all; actually, they show a slight drop. Should we not be told that this is much better than expected?

Hurricanes were the stock image of former US vice-president Al Gore's famous film on climate change, and certainly the US was battered in 2004 and 2005, leading to wild claims of ever stronger and costlier storms in the future. But in the two years since, the costs have been well below average, virtually disappearing in 2006. That is definitely better than expected.

pt1

It's amazing how many times the sceptics can repackage the old 'frost this morning, therefor no global warming' argument and pretend they have something new.

But this is not at all what we have seen. And this is true for all surface temperature measures and even more so for both satellite measures. Temperatures in this decade have not been worse than expected; in fact, they have not even been increasing. They have actually decreased by between 0.01C and 0.1C a year.

Crap. The people who come up with this BS never actually plot the temperature, because that would expose their lie.

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Environmental campaigners probably would. Isn't that what they do? Environmental scientists on the other hand, just present the facts, and some interpretation.

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That's too vague a statement to defend, Bjorn. Give some examples. Which models? Which inputs? - For example if we did some modelling 10 years ago, using some predicted Greenhouse emissions and subsequently found that emissions had increased more than expected, would that be a fault of the model or just a failure to predict the increase in emissions?  

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All I can say is that Bjorn has changed his tack. He was the one that previously said that Global Warming will be good for you - and even better for polar bears

Now he's done a total about-turn. He has now decided, based on a single solar cycle  (and by the way we're currently around the minimum) that  - wait for it  - Global Warming isn't even going on.

Now I know that even if he is just an economist in scientist's clothing, Bjorn knows full well about the 11 year etc Solar Cycles. Come on - he must know. They teach kids that sort of thing in primary school - even in Denmark.

Shooting the messneger muso...  a favourite past-time for you deniers.

Grendel,

I'll give you the benefit of the doubt. Why don't you explain to us how they derive past temperatures from Ice Cores? No cutting and pasting allowed- just use your own words.

After all, this data is used by denialists and you seem convinced that they are right (even though they have different messages)

By the way, here is Gristmill's take on the latest fad by denialists that the world is actually cooling:

http://gristmill.grist.org/story/2008/5/2/115552/7430/

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Or are you projecting Beo?
I have not seen any post from muso to validate your statement.

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What modelling?
Are you stating that ALL modelling is inherently flawed?
Do you have a specific model in mind?
If you do, I am sure that you would be better served to use that specific case, and argue for it, rather than use a blanket statement without any justification.

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I have seen muso question opinions proffered as scientific, and then give reasons why he has issues with them, and offer references to sholarly opinion to show why he disagrees.
I think we would be more accurate to call that "critical analysis".

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I haven't seen muso defend unsubstantiated propaganda, perhaps you could provide an example of him doing so?
If not, do not try and lump all scientific opinion as being equivalent to tabloid sensationalism, which though it does exist, does not negate the validity of the other.

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Got any statistics to back that up?

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Like "It is cold today, so global warming is a lie?"
Got any more gems of anecdotal wisdom to impart?

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Sorry I must have missed that, what "evidence" has he denied?

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Who has provided you with that fact?
How did they quantify the political to scientific ratio?

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Is this the, "It's not happening, but if it is, then it will be good anyway" argument?
If so, please advise the half of you that thinks it isn't real to fight it out, with the half of you that thinks it is, but it will be good for us.
Then you can stop having to argue with strangers.
Unfortunately for you, you will not even be half right.

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I have seen that argument qualified and explained, do YOU consider that denial?

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I thought everyone had agreed we are in a warming period, even the denialists, and just that they were still arguing against actually trying to do anything constructive to mitigate, as much as possible, exacerbating the situation?

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I have not seen anyone deny that the earth has cycles of warming and cooling, I have seen many refer to the timeframes involved, and point out the uncharacteristic rate of change we are currently experiencing, as you well know, but do not let truth slow down your assault on sensible behaviour.

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Yes it will, god yes, it certainly will.

Grendel wrote on Oct 16^th, 2008 at 9:01am:


It is complicated, but the usual statement made by Climate Change deniers compares weather to climate. They are totally different. Weather is stochastic (chaos theory), whereas climate is largely deterministic, especially when it comes to predicting single variables such as CO2 content and global mean temperatures over a given year. Believe me, I know just how complicated the current climate models are having worked with their great grand daddies at Monash in the 90's. The point is that even taking the earliest models, if you input the CO2 concentrations for the years since then, the global temperature rise is pretty easily predicted. It's not perfect of course, and the biggest anomalies occur in the Polar regions. Modelling has improved dramatically even in the last 3 years, and guess what? they don't show a cooling trend in the latest models either.

After all, it's basic physics.

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All science is flawed. We don't yet have a grand unifying theory of everything. It may be flawed, but it's the best we have at the moment, and something like 28 independantly developed modelling systems worldwide all point to the same general conclusion.

We could all throw our arms up in the air and say - electronic theory is flawed. We don't know why Avogadro's number is 6.0221367·1023 particles/mol or why the Boltzmann constant is 8.617385·10-5 eV/K or why an electron has a base mass of 9.1093897·10-31 kg. We basically have to work with them.

We could all say that science is flawed. Let's not manufacture any new computers until we work this thing out. We don't understand the basics well enough.   

Equally, faced with the fact that we are pumping CO2 into the atmosphere at rates we can measure extremely well (we have the bean counters to thank for that) should we say - hey maybe we should try to measure this effect as accurately as possible. All our scientific observations show that this is pretty dodgy behaviour.

or should we say

- nobody can possibly measure this effect, so let's just pretend it doesn't exist?

What do you think?

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The only propaganda is coming from fringe figures who are not even qualified to comment. The bulk of scientific opinion is fully behind the fact of anthropogenic global warming. That includes National Academies from every single country in the World.

There isn't even a single serious researcher among the denialists. They even use data like the ice core data from Vostok that is the work of real scientists.

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Well they do, but Deuterium is the primary proxy in virtually all the published research from Vostok and Law Dome, and the Greenland cores. You can use either δ18O or δD, but δD has been used in the past.

Do you understand how Deuterium can be used as a proxy for temperature?

Do you understand why a trapped bubble of air doesn't simply lose its CO2 to the surrounding ice over thousands of years, or the technique that they use to shave wafer thin layers of ice at a typical temperature of -40 C ?  Do you understand the basics behind the data collection? Most of the skeptics don't, but they are still quite happy to use it.

Grendel wrote on Oct 16^th, 2008 at 9:01am:


Again it's ludicrous to suggest that anybody could be denying that. Exactly who is denying that there have been no past Ice Ages and interglacials?

The difference is the enormous rate of change, and the fact that the CO2 levels have increased to a level way above anything seen in the past - Like 385ppm compared to about 300ppm.

We're actually in a period of the cycle where the earth should be cooling slowly. In fact the data shows such a cooling trend over the last 8000 years or so prior to the beginning of industrialisation.

You've raised a lot of points. I have work to do, and I'm not cutting and pasting anything, so it will take time to reply to all your points in detail.