Discounting

Were there any peeping Toms in Island Bay last Wednesday they would have been in for a shock. At 7.21pm, towards the eastern edge of the suburb, a man could have been spotted leaping from the bath, and running naked into the lounge shouting 'I've found it!'. Which was a bit of an undue claim, as it happens, as I hadn't found anything. I'd just finally got my head around the concept of discounting as it relates to climate change. All this was thanks to a very handy paper from Geoffrey Heal of Columbia University [pdf]. Heal's paper also explains how William Nordhaus is able to get such counter-intuitive results from his economic models as to whether or not we should do anything about climate change. Nordhaus, while admitting that climate change is real and serious, argues that the economics of the matter suggest that we do little. Nordhaus's models have been used by people like Bjorn Lomberg to suggest that we should turn a blind eye to the issue and by others to 'prove' that the Stern Review on climate change is wrong.

My recommendation is that you read Heal's paper yourself to get an understanding of all this. What follows is just my own attempt to crystalise my learning by trying to explain it. I may get it wrong.

Discounting is a tool that economists use to help us weigh costs and benefits across time.

There are several important components to any discounting equation.

The first of these is the pure rate of time preference, which is a function that reflects, in Heal's words, "the rate at which we discount the welfare of future people just because they are in
the future".

A rate of zero will mean that we discount their welfare not at all. Rates greater than zero will suggest that we place less value on their lives. Stern chose a pure rate of time preference slightly higher than zero to take into account the fact that there is a slight chance that there may be no future generations (if, for example, the Earth is hit by an asteroid). If you choose rates much higher than Stern's you are essentially saying that the lives of people living in the future are less valuable than those living at present. Discriminating across time in other words. Like all forms of discrimination, discrimination across time is hard to defend in any ethical sense. Yet a surprising number of people who call for little action on climate change on economic grounds are doing so because they make use of models with high pure rates of time preference. Their argument is, in effect, that, we shouldn't take action now because your grandchildren don't matter as much as you do. Seriously.

The next important component is simply the degree to which you think consumption will increase between now and the day of reckoning. This seems simple enough, yet as Heal points out most economic models of climate change are based on a simple consumption function that uses a single consumption good. In reality we consume many goods, and there are important ones of which our consumption may decrease, despite increasing overall consumption. Goods (services) related to natural capital may, in particular, decrease as a result of climate change. And these are some of the goods most important to our wellbeing. The models, in other words, are a bit fuzzy on the stuff that matters. They're also fuzzy on distributional issues (i.e. who does the consuming - rich or poor).

The third important component to our equation is the impact of consumption on utility (wellbeing). Perhaps one of the most sensible assumptions that one can make in economics is diminishing marginal utility. That is, the more we have, the less the next unit of consumption will contribute to our wellbeing. So when discounting a number is included into the equation to reflect the fact that future changes in consumption will be less important than current ones because we'll be richer then (and diminishing marginal utility would suggest that a change in consumption of value x will have an impact of y on wellbeing now but less than y in the future when x is greater). One thing to note is that Partha Dasgupta takes Stern to task for under assuming diminishing marginal utility. I'm not sure Dasgupta is right to do this but that's a post for another day. Another point to note is that there are also distributional issues at play. Most regimes for addressing climate change are structured so that wealthier nations bear the brunt of the costs. On the other hand if we do nothing it may be the poorest who are hit hardest - so therefore diminishing marginal utility could be inserted into a model in a manner opposite to the way it is used at present. Meaning that it would increase the case for action rather than decrease it.

Now, where was I? Oh, that's right, so what's the matter with Nordhaus's model. In a nutshell he calculates the pure rate of time preference from the observed rate of return on capital. Heal details all the problems with this but the most glaring one to me is simply that Nordhaus is confusing 'is' with 'ought'. Which is just so wrong in this instance it isn't funny. There are also all sorts of other problems including the way risk is managed and the assumptions needed to even consider deriving discounting from the rate of return to capital but you're better reading them from Heal's mouth than mine. I gotta run now...dinner needs to be cooked...but in the meantime remember this one thing:

Nordhaus's work like so much in economics brings with it the veneer of certainty that comes with numbers and maths. But underneath the surface is a much less clear world - one of philosophy. At the very least this ought undermine the tone of certainty with which people appeal to Nordhaus when they argue against action on climate change. But I also think it's worse than that. I think Nordhaus gets the philosophy horribly wrong. As far as dicsounting goes, we ought to discount Nordhaus.

[Update: added a bit more under diminishing marginal utility.]

You're Banned!!!!

A while ago I made a promise to myself not to comment on anymore of Poneke's climate change threads. Doing so had clearly become pointless. Poneke maintains a certainty of opinion completely unjustified by his or her understanding of climate science. And he or she just gets offended when you point out the errors in the posts.

Foolishly, though yesterday I commented again, lured in by a discussion of William Nordhaus and discounting (something that is worth discussing). Of course I couldn't resist the usual error correcting and, lo and behold, there I was - banging my head against a rock again.

So that does it. I'm banned! Or, at least, I'm banning myself. I know it's meant to work the other way in the blogosphere. But I really need to learn to focus my time on things constructive. And arguing with climate change deniers (as opposed to genuine sceptics, who might actually be swayed by evidence) achieves nothing.

[Update: Oh, it looks like Poneke has beaten me to the draw. My last comment on that thread (from last night) never made it out of his/her moderation queue. Assuming it didn't get deleted by accident, it would appear that Poneke is about as keen on me commenting on his/her website as I am. Which is great in the sense that it provides me with help in observing my ban. Not so good perhaps in what it reveals about Poneke, who claims to be opposed to any attempt to silence debate on climate change but possibly isn't so willing to apply the same approach to their blog.

This is fair enough, up to a point: freedom of speech is a society wide principle and people's blogs are their own property. They needn't give a platform to those they don't agree with. Nevertheless, given that my comment was neither abusive nor trolling - it was merely a response to Poneke's response to me - to disappear it with out any comment or acknowledgment just seems rather dishonest. Creating the impression that I had no response to Poneke's Homer Simpsonesque comeback on the subject of statistics.]

[Update 2: Anyone seeking a detailed critique of the Great Global Warming Swindle should have a look at this. Hat tip and thanks to George Darroch]

Oh my Gored

As temperatures rise, denier tactics plunge. They're now doctoring Al Gore interviews so they can claim he is being misleading about science.

Gore's law plus active dishonesty - these people can not be called sceptics in any reasonable sense of the term.

Via comments at Deltoid.

How many...

Inspired by Gareth, I couldn't resist:

Q: How many climate sceptics does it take not to change a light bulb?

A: Approximately 100. 1 to say that the current absence of light is the result of natural solar cycles and the other 99 to disseminate this finding through their 'science organisations' and oil industry funded think tanks.

[Update: This is cool. Robert Butler, the author of the original climate change light bulb joke has blogged about the spread of the meme, very kindly stating that my own humble attempt above is his favourite derivative thus far. Thanks Robert!]

More Great Climate Change Humour...

...at Gareth's place.

Less Loveable with Every Minute

It's been a long time since I bought the Listener. Such is its trajectory of descent now though, that I would be embarrassed to even flick through it queuing at the supermarket.

Wings, Wings!

Via Robert Butler I discover that, thanks to Tim Lambert, Gore's Law made it as far as Grist and Andrew Sullivan. I'd be lying if I said I wasn't rather chuffed...thanks Tim.

Denier Cricket

As kids, on long car journeys, my friends and I would amuse ourselves with a game called Car Cricket. The rules were pretty simple: watch the traffic heading in the other direction, every vehicle that passed was a ball. If it was a green car you got a single. If it was blue you got two runs. A yellow car scored you three and a truck of any colour was a boundary (4 runs). If a bus passed you got a 6. But if a white car passed you, you were out, and it was your friend's turn to bat

Nowadays, on long climate change threads, I amuse myself with a similar sport: denier cricket.

The rules remain simple. Each comment from a denier/sceptic is a ball. The following run schedule applies (note that some comments will blend multiple arguments, in this instance simply take the highest scoring argument):

No Runs
Many leading scientists question climate change / It's all a conspiracy

1 Run
In the 1970s scientists predicted global cooling
Computer Models can't be trusted
C02 isn't the most important Greenhouse Gas
Human emissions of C02 aren't significant compared to natural emissions

2 Runs
The 'Hockey Stick' is broken
The Medieval Warm Period
The Earth's climate has always changed

3 Runs
We can easily adapt
We're better spending the money on other things
We can't trust climate models

4 Runs
It's the Urban Heat Island Effect
Satellites show cooling
The Sun did it!/Sun spots!/Cosmic Rays, Cosmic Rays!

6 Runs
The Earth's climate stopped warming in 1998
CO2 lags temperatures in ice cores

No Ball (you can't go out on this comment/ you get 1 additional run added to what you would have scored otherwise)
Any comment that violates Gore's Law.

Wide (you can't go out on this comment/ you get 1 additional run added to what you would have scored otherwise)
Any comment with some form of Tu Quoque argument or ad hominem attack on climate scientists.

Out! (in the longer test match version of the game)
Any comment that mentions Christopher Monckton by name or which links to an article by him.

Out! (in the shorter one day event)
Any comment that mentions Monckton, Fred Singer, Bob Carter, Jennifer Marohasy or Climate Audit.

This morning, at the PCG, I've already knocked up 18 runs including a 6 off the very first ball...

On a misty Sunday morning in Wellington...

...there have to be better things to do than debate climate change.

But, hey, I plead the XKCD defence.

So here we go.

Unafraid of waking the neighbours on a Sunday morning, Poneke has a post up loudly declaring the global temperatures stopped rising in 1998; and claiming that this fact devastates the case for anthropogenic global warming.

Okey dokey.

Here's my reply (repasted here so my links make it past Poneke's spam filter).

Gosh, I’m hardly awake myself and all of a sudden my pager is blurting noise. Mullah Gore has detected some climate change denial in my quadrant and it’s up to me to silence it. I tell you the hours in this job are lousy. Good thing I am a zealot.

Poneke,

On any given day or any given year numerous factors contribute to global temperature. We are worried about human Greenhouse Gas (GHGs) emissions because they are very likely to lead to a trend of increased temperatures globally*. Such a trend will not be a perfectly linear increase because GHG’s are only one contributing factor to temperature. Amongst this signal we’ll see plenty of noise. The noise which caught your ear this morning is, for the most part, a product from the El Nino/La Nina cycle you talk about. 1998 was an exceptionally hot year because of the powerful El Nino effect that year.

In the Hadley Centre dataset 1998 was the hottest year since records began. In NASA’s dataset 2005 was. In both datasets, if you eyeball a graph of averaged temperatures, this means you’ll see a ‘dip’ or plateau in temperatures this millennium. However, in either dataset, if you place in trend lines the trend (the signal without the noise) is still one of warming.

You will also notice, if you look at a graph of temperature trends since 1975, that there have been two other similar dips. And then the rise continues.

Now, if our ‘dip’ continues for another 10 years, then we’ll have reason to believe that there is something missing in our understanding of the globe’s climate. But until then it simply isn’t accurate to claim that global warming has stopped.

Oh, and no one in the World Meteorological Association is going to be called a denier for the simple reason that the don’t deny anthropogenic climate change. From Reuters:

OSLO (Reuters) - Climate change is still nudging up temperatures in the long term even though the warmest year was back in 1998 and 2008 has begun with unusual weather such as a cool Pacific and Baghdad’s first snow in memory, experts said.

“Global warming has not stopped,” said Amir Delju, senior scientific coordinator of the World Meteorological Organization’s (WMO) climate program.

Last year was among the six warmest years since records began in the 1850s and the British Met Office said last week that 2008 will be the coolest year since 2000, partly because of a La Nina event that cuts water temperatures in the Pacific.

“We are in a minor La Nina period which shows a little cooling in the Pacific Ocean,” Delju told Reuters. “The decade from 1998 to 2007 is the warmest on record and the whole trend is still continuing.”

_____________________________
*And remember here, that global means global. Temperatures in specific locations may perform quite differently.

Climate Fallacies Debunked Funnily (an ongoing series)

A classic claim from climate quacks is that, because CO2 rises lag behind temperature rises in ice core records, C02 produced by human activities can't possibly be contributing to climate change. A nice sensible explanation of why this is nonsense can be read here. But if you prefer a chuckle with your debunking, you won't find any better than this piece of pure joy from Tim Lambert's Deltoid.

CO2, warming, and causality

Category: Global Warming
Posted on: March 31, 2008 10:47 PM, by Tim Lambert

z, in comments:

"CO2 is not causing global warming, in fact, CO2 is lagging temperature change in all reliable datasets. "

See also my forthcoming paper: "Chickens do not lay eggs, because they have been observed to hatch from them".

Gore's Law In Action

Readers of my last post, on the subject of Gore's Law, may have been of the mistaken impression that Gore's law only apples to blog comments boxes. Kiwi blogger David Farrar aptly demonstrates that this is not the case, flying into action in the first half of the first sentence of an actual blog post:

Like a medieval religious zealot, Al Gore claims that those who still doubt that global warming is caused by man are the equivalent of those who think the moon landing was faked.

A medieval religious zealot? I was unaware that the moon landing was actually an issue in the Middle Ages. Oh well...

DPF continues:

Scientific debate is in fact the exact opposite of lunatic conspiracy theories.

True enough, but are climate change 'sceptics' really engaged in a scientific debate? Hardly. While there are uncertainties, there is next to no disagreement amongst climatologists about the fact that current climate change is human induced and a real concern. There is no real debate. What we have instead is climate 'sceptics' grasping at any evidence whatsoever that appears to support their theories though while diligently ignoring everything else. And this is something they have in common with conspiracy theorists.

Indeed, DPF himself, while grudgingly acknowledging that there is "fairly wide consensus that greenhouse gas emissions contribute to warming" attempts to counter this concession by emphasising uncertainties using a quote from an article in the Australian. The quote's from an interview with Jennifer Marohasy in which Ms Marohasy claims that new satellite data and recent temperature trends provide us reason to doubt the danger presented by climate change.

Marohasy is not a climatologist, of course, and her employer has a rather comfortable relationship with oil companies, but none of this would matter if her claims were actually right. The trouble is, they're not. She's not credible, her claims are wrong and one has to wonder why, out of all the good information on climate change on the internet, DPF had to choose her as a source. In doing so he certainly did nothing to counter Al Gore's supposition about climate 'sceptics' and conspiracy theorists.

[Update: Edited second to last paragraph for clarity]

Gore's Law

In 1990 Internet Lawyer and writer Mike Godwin gave the world Godwin's law, stating that:

As a Usenet discussion grows longer, the probability of a comparison involving Nazis or Hitler approaches one.

The rise and rise of Internet Climate 'sceptic' nonsense means it's time for an update.

Gore's Law

As an online climate change debate grows longer, the probability that denier arguments will descend into attacks on Al Gore approaches one.

Have a look. This Hot-Topic thread begins to Gore after about 21 comments. While this Poneke thread is Gored badly almost from the start. There's plenty of Goring going on in this thread too. And some organisations, such as the Competitive Enterprise Institute have grabbed both horns, so to speak, and Gore right from the outset.

Here's a hint. Al Gore could be short, evil and fond of child sacrifice. He could emit more CO2 snoring at night than Christopher Monckton does all year. And his movie could be even more inaccurate than the Great Global Warming Swindle. But this wouldn't change a thing. What matters is not Al Gore's character but science. And, in the case of climate change, it's awfully compelling.

[Update: And, not willing to wait until the comments box, David Farrar Gores hard right at the outset in his latest piece of climate blather.]

Special Muriel Newman Bonus Bonus

A couple weeks ago Muriel Newman's breathless report back from the very exciting climate change denial conference she attended in New York made its way in a slightly edited form into the Dompost (Welington's local paper). It's futile, but I couldn't resist - so I wrote a letter to the Dom. I don't think they've published it, but I don't read the Dom enough to know for sure.

Anyhow, here's the first draft of the letter (I shortened it a bit to meet the Dom's word limit).

In her oped ‘Climate Change: we didn’t do it’ Muriel Newman breathlessly informs us that “[l]ast week 500 people, including 200 leading climate scientists and economists, gathered in New York to address the question of whether manmade global warming is really threatening the existence of our planet”. Reading over the misconceptions and factual errors in the rest of her column it’s hard to escape the feeling that there must have been an awful lot of economists at the conference.

Newman, for example, writes that, “[s]ince 1934 has emerged as the warmest year in recent times, manmade greenhouse gas emissions cannot possibly be to blame.” Globally, 1934 was not – by a long shot – the warmest year in recent times. It was probably the warmest year in the United States, but there’s a reason why the word ‘global’ is included in global warming – because the phenomenon has to do with temperatures for the globe as a whole. And globally temperatures have risen significantly since the 1930s. It’s true that there was a period of cooling over the middle part of last century but the reason for this is – aerosol pollution – is well known and the trend does not disprove the theory that the current episode of climate change is human driven.

Newman also claims that some of the temperature rises reported on by the IPCC are the result of the urban encroachment on previously rural temperature stations. How then does Ms Newman explain the rise in temperatures recorded by satellites? God only knows our cities are sprawling, but not that far.

Just to be clear, that isn't an attack on economists in the first paragraph. I'm just pondering how so many experts could know so darn little about the Earth's climate.

Special Muriel Neuman Sea Level Bonus

In her online opinion piece on climate change Muriel Newman states with some confidence that:

Predictions of dramatic sea level rises were categorically discredited. The sea has been rising by a constant 18cm a century (1.8mm a year) and is thought to be driven by the melting of the West Antarctic Ice Sheet. The fact that this started an estimated 18,000 years ago and is expected to continue for another7000 years shows that humans are not to blame!

Compare this with someone who has the unfair advantage of actually knowing what they are talking about:

But around 18,000 years ago earth began to deglaciate, bringing us to the present interglacial. As a result, sea level rose about 120 m over a span of about 10,000 years, albeit irregularly...The situation began to stabilize around 8,000 years ago, with a much slower rate of change, and about 2,000 years ago even greater stability became the order of the day. Sea level is believed to have been remarkably constant from the 1st century until the 19th; studies from a number of geographically diverse regions provide convincing evidence that the rate of change was no greater than 0.2 mm/yr. This situation remained in effect until the middle of the 19th century, when sea level began to rise; since then it’s risen at an average rate of around 1.5 mm/yr, although the rate has been variable.

Quack!

I'm not supposed to be blogging but...

...Muriel Newman is quacking and it's hard to resist.

A conservative friend of the family recently sent me an email that was more or less a cut and paste of this post from Ms Newman's website.

I replied as follows:

That's an interesting email. It's also rather misleading. I'm not a climatologist and when I can spot elementary errors it leaves me inclined to think that the person who wrote it probably isn't qualified to comment on climate science.

Here's a couple of problems with the email.

1. They write: "Scientists have shown that in the earth’s geological past, concentrations of carbon dioxide have been up to 20 times higher than they are at present and temperatures have been considerably warmer."

Personally, I doubt the 20 times higher figure but it's possible, the Earth has a long history. Humans have only been around for a very short part of it; human civilisation for even less. And that's the point: it's true that temperatures have been considerably warmer in the distant past. So warm, in fact, that Crocodile like creatures lived close to the arctic circle. Which is good news for crocodile like creatures but rather disastrous for us humans - do you really think that we could endure this level of climate change (rendering most of the world's temperate zones uninhabitable) without huge suffering. The other point that the author is trying to make, of course, is that because the historical climate variations have been greater than those observed at present, then current variation may not be natural. This is incorrect. We know, thanks to basic atmospheric physics that - everything else being equal - more CO2 in the atmosphere will lead to higher temperatures. We know CO2 levels are rising (thanks to undisputed measurements). We know thanks to Carbon Isotope measures that human activity is causing this rise. We also know that temperature is rising. And, no known combination of known climate forcings which excludes the input of CO2 can explain this observed rise. In other words: the Earth has warmed naturally in the past; it is warming now - this is not natural.

2. They then write: "The two most recent warming periods occurred during Roman Times from 200BC to 600 AD and Medieval Times from 900AD to 1300AD, when Greenland was green and grapes grew in England. The Little Ice Age followed." This is simply not true. In some climate reconstructions the medieval warm period is close to being as warm in present (in most it's not even close); however, in no reconstruction is it warmer than present. Grapes, I might add, still grow in England. And Greenland was never green. Leif Erikson (or Eric the red - I get the two mixed up) named it Greenland to attract other settlers to the continent - one of history's oldest real estate swindles.

3. They then write: "Current temperature trends show a warm period between 1920 and 1940, followed by a cooling phase. There was a sudden warming surge from 1976 to 1978 and another in 1998. Since then the weather has been cooler." The cooling phase was caused by aerosol pollution - as countries tightened up on this (through clean air acts and the like) temperatures began to warm again. The 'surge' up to 1998 was caused by abnormally high temperatures in that year - a result of El Nino. All of this is common knowledge. That no one at the conference bothered to mention it makes me wonder about the credibility of the experts present.

4. They then write: "The year 1934 has emerged as the warmest of the 20th century." This, if I recall correctly, is also false. 1934 was the warmest year on record *in the United States*. It's called global warming for a reason - and the United States is not the globe.

5. I could go on, but dinner awaits. I will note on thing though - the IPPC does not run its own research. It assesses all the peer-reviewed research currently available. Its conclusions reflect the state of the science - not one conference run by an organisation that gets a bundle of money from Exxon Mobil and which has its own ideological bone to pick.

Anyhow, it was an interesting email, so thanks for that. Speaking of a warm climate, lovely weather today no?

cheers

Terence

They then posted my reply on Ms Newman's website. And she replied (and I received the reply via email from the family friend).

Here's my reply:

Thanks for your reply. I take it that the message is actually from Muriel Newman and that she has replied on a forum where you pasted the contents of myf first email?

Also I need to apologise in advance for two things:
1. My reply will be brief.
2. This is going to be my last reply on this subject matter.

As I'm sure you can appreciate, I have quite a lot on my plate at present and I could do with relaxing at least some of this weekend (1 day is already liekly lost to work), and while debating climate change can be enjoyable, it isn't relaxing.


Greenland
Ms Newman is right: medieval Norse settlers in the sourthen coastal regions of Greenland did indeed graze cattle and grow crops. Grazing and agriculture - and the Norse settlers - were put paid by the Little Ice Age, where temperatures were significantly cooler than during either the Medieval Warm Period or the present day. Does this mean that the Medieval Warm Period was warmer than today? No. First Greenland is only 1 country (and remember we're talking about *global warming* here). Second, my understanding is that the current climate in southern Greenland is once again warm enough to support such agriculture. The reason it is not is because, thanks to the wonders of globalisation, it's far more efficient for Greenlanders to import such food (a good example of comparative advantage Ricardo style.)


The Hockey Stick
Mann et al's 'Hockey Stick' climate reconstruction has most certainly not been "well and truly discredited". It has been challenged, but these challenges themselves are of questionable merit. If you are interested you can read about the errors in McIntyre & McKitrick's putative refutation of the hockey stick here: http://tamino.wordpress.com/2008/03/06/pca-part-4-non-centered-hockey-sticks/

Let us, for argument's a sake, assume that the Mann et al's reconstruction was wrong, however. Would that disprove the theory that current climate change stems from predominantly human sources? In a word: no. For a start Mann is not the only person working on historical climate records. If you go to the following link you can look at the various credible climate reconstructions of the last 2000 years super imposed on the same graph:
http://en.wikipedia.org/wiki/Image:2000_Year_Temperature_Comparison.png

Some of these are Mann's work but the majority are not. You will notice, of course, that in none of the reconstructions does the Medieval Warm Period come close to being as warm as current temperatures. Even if Mann's hockey stick graph was to be discredited this would do nothing to change this fact.

It is also worth noting that, even if all these reconstructions were wrong, this still wouldn't prove that current warming was not human generated. As I said in my last email, we know from basic physics that, everything else being equal, if CO2 levels in the atmosphere rise, temperatures will follow. We know that CO2 levels are rising. We know from Carbon Isotope measures that we are the source of this CO2. And we know that temperatures are also rising. This alone is reason for considerable concern.


The Relationship Between CO2 and Temperature in the Paleoclimate Record
Ms Newman is broadly correct when she says that CO2 lags behind temperature through much of the paleoclimate record. She misses the point here though. Prior to technology providing humans with the means to alter the Earth's climate, changes in the Earths climate were probably - in the first instance - primarily driven by orbital variations or fluctuations in solar activity. These initial temperature variations are likely to have then triggered a feedback process through which CO2 was released into the atmosphere (possibly from warming oceans). This then exacerbated the initial warming trends leading to the large variations in temperature visible in the paleoclimate record. This is is interesting but does nothing to disprove the theory of AGW. Recent observed solar fluctuations do not correspond to global temperature trends (the graph Ms Newman shows is long refuted and only tracks the US temperature record, anyhow). And, as I noted above, we have definitive proof of the fact that the rise in CO2 in the atmosphere is caused by human activity (i.e. it's not part of some feedback loop).


The Impact of Human CO2 Emissions verses Natural Quantities of CO2 in the Atmosphere
I have not had time to check the numbers that Ms Newman quotes from Robinson et al and it would not surprise me if they are wrong. Nevertheless, the basic point stands. Compared to quantities of CO2 to be found naturally in the atmosphere and biosphere, human emission levels are not large. But the important point is that naturally, over a period of broadly stable temperatures, naturally occurring CO2 is in balance. Sources of emission are countered by sources of absorption. The criticical thing here is that we humans are disrupting this balance. That is all that is required to trigger climate change.

I hope that this is of some help to you.

Terence

Quackidy quack, quack, quack

It looks like a duck. It quacks like a duck. Yip. It's another Poneke post extolling the virtue of climate, cough, scepticism.

I replied in comments. I'm reposting my reply here because Poneke's spam filter appears to be zapping link-rich comments, and reposting here seems like the best way of providing some references to my claims while not getting zapped.

My comment is below but, before I start, I do want to acknowledge one thing: Poneke is a great writer and has an excellent blog (climate lunacy notwithstanding). I wanted to mention this because I only ever comment on Poneke's* climate change stuff here, and that's not a complete representation of the quality of his/her blogging.

==My Comment==

Here we go...

Many eminent scientists continue to be concerned at the media and political hysteria that rages around the climate change issue.

Not true. The vast majority of climate scientists are concerned not by media and political hysteria on climate change but rather the fact that we are failing to take action to prevent it. Can you name me 10 climate scientists (defined as people trained in climatology with peer reviewed papers in respected climate journals) who share the views of Linzden?

One of them is Richard S Lindzen, the Alfred P Sloan Professor of Atmospheric Science at the Massachusetts Institute of Technology.

And seeing as Lindzen feels free to speculate on the motives of other climate scientists let us return the favour. From PBS:

Dr. Lindzen has claimed in Newsweek and elsewhere that his funding comes exclusively from government sources, but he does not seem to include speaking fees and other personal compensation in this statement. Ross Gelbspan, who did some of the first reporting on climate skeptics' links to industry, wrote in Harper's Magazine in 1995: "[Lindzen] charges oil and coal interests $2,500 a day for his consulting services; his 1991 trip to testify before a Senate committee was paid for by Western Fuels, and a speech he wrote, entitled 'Global Warming: the Origin and Nature of Alleged Scientific Consensus,' was underwritten by OPEC."

Dr. Lindzen is a member of the Advisory Council of the Annapolis Center for Science Based Public Policy, which has received large amounts of funding from ExxonMobil and smaller amounts from Daimler Chrysler, according to a review Exxon's own financial documents and 990s from Daimler Chrysler's Foundation. Lindzen is a also been a contributor to the Cato Institute, which has taken $90,000 from Exxon since 1998, according to the website Exxonsecrets.org and a review Exxon financial documents. He is also a contributor for the George C. Marshall Institute.

You write:

“Climate is always changing,” he writes. “We have had ice ages, and warmer periods when alligators were found in Spitzbergen.

Yes but at present no known natural phenomenon can explain the current change and we know, thanks to basic physics that, cetrus paribas, rising levels of C02 in the atmosphere will lead to higher temperature. And we know that C02 levels are increasing at unprecedented rates at present. And we know, thanks to Carbon Isotope measures, that human actions are causing this rise. So we have very strong reason to believe that the bulk of the current variation is not natural. And, therefore, that we can do something to arrest it.

As for 'gators at the poles, how cute. If Lindzen or anyone thinks that human civilization can survive a transition over the space of a couple of centuries to this sort of climate state without immense suffering they are dreaming.

You then write:

You won’t often read articles by outspoken climate scientists like Professor Lindzen in the daily news media

Not true. As Naomi Oreskes and others have shown, climate change "sceptics" get almost equal coverage in the mainstream media (see how often Lindzen et al get coverage in the WSJ for example). The one place they don't get such equality of coverage is in peer reviewed journals. This is for one simply reason: their science is bunk.

Then you write

I am not someone who would try to claim that the recent unusual cold snap in China, or the one in Greece (it was sno:wing, heavily, in Athens this week) are evidence against global warming, despite the tendency of climate change promoters to say every major storm or drought is proof of their position.

Once again, not true: you actually did something very similar several weeks ago with your ill-informed 'gotcha' post on the Wellington temperature record.

Then you write:

Global warming theory postulates a rise in average temperatures over a century, not a year. But I can’t help noticing the accumulating evidence that average global temperatures have not risen during all of this century, after rising in the decade beforehand, despite the rise in carbon dioxide emissions caused by the greatest economic growth the entire world has ever enjoyed.

Huh? Do you mean over the last hundred years? If so, then temperatures rose significantly over this period of time (careful to look for th right graph here). The did not rise over all of the last 100 years only because of the offsetting forcing of aerosol pollution. Something that is well known.

Still at least you and Reid have found a conspiracy theory you can agree upon. :)

P.S I'm going to repost this comment at my blog, with links. That way those who are interested can check my claims while I avoid the risk that your spam filter nabs the links here.

_______________________
*Update: Gender specific term modified - thanks George.

Quack? Quack, Quack. Quack! Quack! Quack, Quack, Quack!!!

Years from now, when we are dealing with the consequences of anthropogenic global warming we will look back and wonder just how in God's name a supposedly reputable paper could publish nonsense like this in the name of forestalling action.

The article is so illogical it's actually hard to Fisk.

The core argument, as best I can determine, revolves not around science but around words.

Environmentalists, you see, use the term 'climate change' as shorthand for anthropogenic climate change. But, the writer informs us, the Earth's climate has always changed. Therefore the term 'climate change' is misleading. Therefore anthropogenic climate change is not real.

People also, we learn, talk about 'carbon trading' and 'carbon emissions'. This is misleading as carbon and carbon dioxide aren't the same thing and using the term carbon in place of carbon dioxide makes people think that a natural gas is a dirty pollutant. Therefore Carbon Dioxide emissions can't be causing climate change.

Arguing this is a bit like saying that people use the term radiation to refer to nuclear radiation. Therefore nuclear radiation is harmless. And, anyhow, radiation is natural, therefore it can't cause cancer.

Having wowed us with words, the oped concludes by telling us that relationship between rising CO2 and rising temperature is "a point of strong debate among climate scientists". After all the linguistics, a nice simple lie.

Why does this nonsense keep getting written? Why does it keep ending up in the Herald?

Quack!

In honour of the continuing sound of quacks emanating from Poneke's blog. I've created a new link list over to your right. Countering Climate Quackery is a handy list of resources for countering 'climate sceptics'.

My current favourite is Greenpeace's Exxon Secrets, through which you can follow the dollar trail from Exxon to the climate sceptic of your choice. Our own Vincent Gray and Chris De Freitas make cameos. Of course, at the end of the day, it doesn't matter who's funding you: if you're science is right it's right. However, the list is interesting - especially given the oft' repeated sceptic claim that those climate scientists who are concerned about global warming are only in it for the research money.

I've also included Mark Lynas on my list. Lynas is someone I hope Poneke reads. I hope this because, in his first post professing climate 'scepticism', Poneke made the following argument about science, certainty and climate change:

Science at this global, theoretical level is never settled, despite the claims of the climate change lobby. Science is about testing and disproving theories to arrive at new ones to test and disprove again and again, always increasing scientific knowledge, not fossilising it in stone like the Ten Commandments, which some seek to do with climate science. Fortunately, science will not be fossilised and climate science will continue to develop.

In my reply I pointed out some of the problems using this argument against action on AGW. However, Mark Lynas, does a better job than I ever could:

Every qualified scientific body in the world, from the American Association for the Advancement of Science to the Royal Society, agrees unequivocally that global warming is both a reality, and caused by man-made greenhouse gas emissions. But this doesn’t make them right, of course. Science, in the best Popperian definition, is only tentatively correct, until someone comes along who can disprove the prevailing theory. This leads to a frequent source of confusion...that because we don’t know everything, therefore we know nothing, and therefore we should do nothing. Using that logic we would close down every hospital in the land. Yes, every scientific fact is falsifiable – but that doesn’t make it wrong. On the contrary, the fact that it can be challenged (and hasn’t been successfully) is what makes it right.

...as a close follower of the scientific debate on this subject I can state without doubt that there is no dispute whatsoever within the expert community as to the reality or causes of manmade global warming. But even then, just because all the experts agree doesn’t make them right – it just makes them extremely unlikely to be wrong. That in turn means that if someone begs to disagree, they need to have some very strong grounds for doing so – not misreading a basic graph or advancing silly conspiracy theories about IPCC scientists receiving paycheques from the New World Order...

Yes, scientific uncertainties remain in every area of the debate. But consider how high the stakes are here. If the 99% of experts who support the mainstream position are right, then we have to take urgent action to reduce emissions or face some pretty catastrophic consequences. If the 99% are wrong, and the 1% right, we will be making some unnecessary efforts to shift away from fossil fuels, which in any case have lots of other drawbacks and will soon run out. I’d hate to offend anyone here, but that’s what I’d call a no-brainer.

Updates

In comments David Farrar has replied to my post on Moore, Minto and himself. He writes:

Oh I didn't advocate property rights alone is the answer. I do advocate that it is a necessary element though as without them no economy has even shown much ability to lift people out of poverty.

Once you have property rights, then there is other stuff to do.

In the broadest possible sense I agree with him, I guess. What I really need to do now is write a full post on what is complicated topic...

Also, In a recent post on climate change, I wrote the following, starting with a quote from a denialist climate quack letter to Ban Ki Moon:

The average rate of warming of 0.1 to 0. 2 degrees Celsius per decade recorded by satellites during the late 20th century falls within known natural rates of warming and cooling over the last 10,000 years.

Which may be true (I haven't double checked) but even so - so what? Once again: we know that we are increasing CO2 in the atmosphere, we know that - everything else being equal - more C02 will mean higher temperatures, and we know that temperatures are increasing in a manner that we can't attribute to any natural phenomenon. Why - given all this - would we need a faster rate of warming than ever observed before to provide us with proof of AGW?

I've just been browsing Gareth Renowden's wonderful website Hot Topic and I read this (written about the same letter):

The current rate of warming is roughly 20 times faster than the last period of rapid climate change, when the world warmed by 5C (on average) over 5,000 years as we emerged from the last ice-age. The current rate of warming is much faster than “natural variability”

So either our letter's writers were spinning utter bullshit or they were disingenuously selecting the one record (satellite data) which might have allowed them to "honestly" make such a claim. Either way there is only one appropriate reply:

Quack!

Climate Change Denial's so Hot Right Now...

...it's all over the blogs, the Herald, The New York Times, Manukau.

For the life of me I can't understand the burrowing ostrich mentality which prompts people to pump out disinformation hoping to forestall action on what is likely to be a very serious problem (and one which will affect us all - sceptics and credulous - alike).

A textbook example of the disingenuity that emits from the deniers camp is the recent open letter to Ban Ki-Moon from a self proclaimed group of climate experts. As always, the vast majority of the 'experts' are not climatologists. And, as always, what they write is misleading (to put it very mildly).

Let's look at one short extract:

z Recent observations of phenomena such as glacial retreats, sea-level rise and the migration of temperature-sensitive species are not evidence for abnormal climate change, for none of these changes has been shown to lie outside the bounds of known natural variability.

z The average rate of warming of 0.1 to 0. 2 degrees Celsius per decade recorded by satellites during the late 20th century falls within known natural rates of warming and cooling over the last 10,000 years.

z Leading scientists, including some senior IPCC representatives, acknowledge that today's computer models cannot predict climate. Consistent with this, and despite computer projections of temperature rises, there has been no net global warming since 1998. That the current temperature plateau follows a late 20th-century period of warming is consistent with the continuation today of natural multi-decadal or millennial climate cycling.

One at a time:

"Recent observations of phenomena such as glacial retreats, sea- level rise and the migration of temperature-sensitive species are not evidence for abnormal climate change, for none of these changes has been shown to lie outside the bounds of known natural variability."

Quite true! And quite besides the point, as none of the aforementioned observations are claimed as key evidence for Anthropogenic Global Warming (AGW) . They do, however, correspond with satellite and other instrumental measures of temperature warming and, as such, provide collaborating evidence - and they give us some idea of the consequences of AGW - but they aren't the key evidence. The crucial evidence for AGW is the rise in temperatures (observable in surface and satellite records) combined with the rise in Greenhouse Gases (GHGs). GHGs, which we know, thanks to Carbon Isotope measures, are human produced; and which we can expect, thanks to our understanding of basic atmospheric physics, to increase temperatures. Moreover, no known natural process, (such as solar radiation), which could otherwise be causing temperature increases is currently trending in a manner which is constant with observed temperatures. This is why the vast majority of climatologists believe that current global warming is human produced.

And while it is true that, current fluctuations in glaciation and the like, fall within the bounds of
'natural' variability, and while there is no reason to believe that AGW will lead to climate change greater than that experienced naturally by our planet in the past, this is no cause for complacency. Natural variability has seen temperatures so warm that crocodile-like creatures lived near the Poles. Do the 'scientists' who signed the letter really believe that humanity could endure the transition associated with such climate change and not experience significant costs in terms of human welfare.

The average rate of warming of 0.1 to 0. 2 degrees Celsius per decade recorded by satellites during the late 20th century falls within known natural rates of warming and cooling over the last 10,000 years.

Which may be true (I haven't double checked) but even so - so what? Once again: we know that we are increasing CO2 in the atmosphere, we know that - everything else being equal - more C02 will mean higher temperatures, and we know that temperatures are increasing in a manner that we can't attribute to any natural phenomenon. Why - given all this - would we need a faster rate of warming than ever observed before to provide us with proof of AGW?

Finally they state that "there has been no net global warming since 1998." Once again they are being disingenuous. 1998 was a particularly warm year thanks to El Nino. This is understood and explained and isn't a threat to computer models or climate predictions. What's more, if you actually run proper trend lines through the 1998 to present data there are still trends of warming. (Two very good posts explaining this are here and here).

God this gets tiresome.