Sunday, September 09, 2012


England has had a cool wet summer. The relevance of this in the debate on global warming is pretty close to nil. Likewise, the cold winters in 2010 and 2011 didn’t tell us much about the long term trends of the world’s climate either. The data that does matter, the average world temperature records, show that temperature rose to about 0.7 degrees centigrade above pre-industrial levels in the years up to 1998. Since then, it has basically stood still. And not all the climate alarmism of all the lefties and greens on this Earth has managed to budge it one iota.

I’ve long struggled to articulate my position on global warming. Obviously, I’m a sceptic about the silly claims about tipping points, massive rises in sea level (we’ve had about 8 inches in the last 150 years) and extinct polar bears. The world isn’t going to see temperatures rise by 6 degrees any time soon, and if it does, it won’t have anything to do with us. But there is also no point in denying the temperature records that do show moderate warming in the last half-century or that carbon dioxide is part of the reason for this. Doubling the level of atmospheric carbon dioxide from pre-industrial levels should lead to an increase in average global temperatures of about 1 degree. This means that we can expect some further moderate warming in the coming decades.

You can only reach the alarming figures of warming of 3 degrees plus by adding feedback mechanisms to the mix. The scientific justification for these mechanisms is that they are needed to explain the past. Climate scientists have found that to get their computer models to reflect temperature records from the last hundred years accurately, they need to add more factors than just carbon dioxide to the mix. Then they extrapolated their models into the future and declared, on this basis, that things would get a whole lot hotter. They might be right. But simply using a model that explains the past to make predictions about the future is scientific garbage. You cannot take a complicated model that you’ve tweaked to fit a certain curve and then rolling it forward. This is about as accurate as a predictive device as tossing a coin. Unfortunately, it is also human nature. We are very good at spotting trends and expecting them to continue. There is even a name for this: it’s called the gambler’s fallacy.

Back in 2001, the IPCC told us to expect rises in temperature of 0.1 to 0.2 degrees per decade. Since 2001, that simply hasn’t happened. Now, there might be good reasons for this tied up with long-term patterns that were not properly understood even ten years ago. But there might just as well be other even more long-term effects that could cause temperatures to fall in the next fifty years, or not, as the case may be. We simply don’t know. And until we have models that have been shown to work in advance of what they are supposed to predict, we can’t rely on them.

That’s why I am sceptical about predictions of future climate. You should be too. But that doesn’t make me a global warming denialist, since I certainly accept the solidly-based past temperature records. I also expect further moderate warming on the basis of the well-understood “greenhouse effect”.

So what am I? Matt Ridley, author of the excellent The Rational Optimist, has the answer. He calls himself a luke-warmist. And that is what I am too. As a luke-warmist, I accept the following aspects of climate change orthodoxy: the world is getting (a bit) warmer; atmospheric carbon dioxide is a major cause of this; and human activity has increased the level of atmospheric carbon dioxide from about 280 to 400 parts per million.

But thereafter, luke-warmists part company with orthodoxy. For instance, I do not claim that the world’s temperature was an optimum in 1970 (or whenever). Instead, I recognise from history that warmer climates have been beneficial in the past and this is likely to remain the case in the future. I reject forecasts of future climate change based on computer models that have not been shown to make accurate predictions. I believe it is abhorrent to encourage poor countries to use expensive energy when cheaper carbon-based alternatives would boost their economic performance. I believe wind power is an expensive white elephant and using agricultural land to grow biofuels a scandal (on this last point, I find I’m in agreement with many Greens). I note most anecdotal reports on the effects of global warming turn out to be false or misleading (from Himalayan glaciers to vanishing coral reefs). I note that the best way to reduce carbon emissions is to use more gas (thankfully there is plenty of it about and the fracking technology to extract it). And finally, I note that climate change propaganda is well-funded and pervasive (unlike climate change scepticism, which has to work on a shoestring).

In short, global warming isn’t yet much of a problem and is more likely to be mildly beneficial. If it does turn out differently, then we should adapt. But the current fad for slowly destroying the world’s economy by artificially increasing the cost of energy isn’t just stupid. Cheap energy drove the industrial revolution and much of the development that has given us such high standards of living today. The oil shocks of the 1970s caused two damaging recessions. Keeping energy affordable when we know the consequences of high prices will eventually be disastrous should be a much greater priority than preventing uncertain climate change.

Note: this post was amended on 14 September to clarify certain points.  It seems that there are only two boxes allowed in this debate - denailist and true believer.  I have tried to make clearer that I am neither.

Discuss this post at the Quodlibeta Forum


Jon Myerov said...

"destroying the world’s economy"

Really? Please explain.

TheOFloinn said...

Heck, the world's been growing warmer for =400= years, since the end of the Maunder minimum. Prior to that, the Vikings were running dairy farms in Greenland and wine grapes grew in Scotland. Was it simply a coincidence that the Modern Warm period coincided with a Solar Grand Maximum?

If you take a growth trend for the rebound out of the Little Ice Age, then superimpose a 50-to-60-year cycle atop it, you not only get the increase, you get the "accelerated" increase of the 80s and 90s as well as the "slowdown" and even "global cooling" worries of the 50s and 60s. It also explains why some folks were worried about melting arctic ice in the 1940s, at the peak of the previous warm spell.

Ilíon said...

" It seems that there are only two boxes allowed in this debate - denailist and true believer. I have tried to make clearer that I am neither."

Shame on you! And, if you're not a True Believer, then you're clearly a Denialist! ;)

Ilíon said...

"Really? Please explain."

He already did.

Diogenes said...

Interesting post.. I find myself in sympathy with your pragmatic approach to the issue of climate change.

However, I remained highly concerned about how the AGW crowd has abused the scientific process (dare I say misbehaved?) with regard to their climate modeling techniques and use of corrupted temperature data.

Also, common sense dictates to me that with any increase in atmospheric CO2, we need to focus on why botanical life is no longer able to absorb those increased quantities of a gas that should be causing plant life to flourish.

The point is that any rise in CO2 emissions should be naturally balanced by an increase in CO2 uptake by global floral, in particular oceanic phytoplankton.

However, this has not been the case. The 20-30% increase in CO2 has correlated strongly with a 20-30% DECREASE in oceanic phytoplanton levels over the past 30 years that we've monitored such populations from space.

CO2 is one critical element necessary for plant growth. But if other nutrients, including trace iron and silica, are absent, phytoplankton cannot grow no matter how much CO2 is available.

Therefore, I think far too little attention has been paid to the late Dr. John Martin's "Iron Hypothesis" and how the lack of trace iron has prevented oceanic flora from increasing it's uptake of atmospheric CO2.

Something to consider in your analysis, IMO.

johnf said...

Like Diogenes, I am also in sympathy with your pragmatic approach.
As one fairly experienced with developing mathematical models of systems, they are best for estimating behaviour within the boundaries of the parameters used to develop them - i.e interpolation.

Extrapolation is moving outside your comfort zone, and betting the whole economy on extrapolated climate models is plain nuts.

Oh dear, I am a denialist too, and not fit for polite company.