Climate debate and factsPosted: July 30, 2008
Reading in the local newspaper last week I was surprised to find the following statement in an opinion piece by Chris Kenny:
People are scorned as “deniers” simply for pointing out the scientifically agreed fact that Earth has not warmed for a decade.
Overall the article, “I’m sick of the scare tactics in climate debate”, is concerned with the rhetoric that currently fills any discussion over climate and so I was curious about the offhand way such a simply wrong fact was thrown in there. In the next paragraph we then had the following:
And that no one has yet proved a link between human activities and/or carbon emissions and climate change.
The second half of this statement could be discussed as the word “prove” can be ambiguous but I was more interested in the first statement, which again is simply wrong.
With this in mind I wrote a letter to the editor and assumed , in this case incorrectly, that it would be simply ignored as that is my first hand experience of any complaints about the standard of journalism in The Advertiser. To my surprise I soon received a phone call from the editor advising me that they would be publishing my letter. Unfortunately The Advertiser does not put it’s letters online, unlike opinion pieces from it’s journalists, so I can’t show you the link to the letter. However I can simply show you what I wrote as I kept a copy. What is below is in two parts, the first part is what was published, the second is what was left out.
“Chris Kenny’s latest opinion piece with a subtitle of “I’m sick of the scare tactics in climate debate”, will I’m sure be leading to pots and kettles eying each other off. Chris makes the claim “People are scorned as “deniers” simply for pointing out the scientifically agreed fact that Earth has not warmed for a decade.” This is simply wrong and not a fact. The scientific consensus is currently well represented by the following statement from the Hadley Climate Center, “A simple mathematical calculation of the temperature change over the latest decade (1998-2007) alone shows a continued warming of 0.1 °C per decade.” Now, people can argue about other issues and what this means, however the fact of observation is not, unless you care to deny reality.Chris further states “And that no one has yet proved a link between human activities and/or carbon emissions and climate change.” Addressing the first part of this claim scientist have clearly demonstrated that the increasing CO2 levels correspond with a decreasing C13/C12 isotope ratio which is due to human burning of fossil fuels and not a natural process.
Simply put Chris, what you said is wrong.
Now, no-one is going to deny there are alarmists in both camps on this topic which really doesn’t help but could we please respect the facts and concentrate the debate on areas of uncertainty?”
The section that was left out of the published letter, for completeness was:
“And as for “Why the scare campaign”? Chris, of all people, being an adviser to a government should know. Because they work, regardless of which side of the fence you live on. The media could perform us all some justice by promoting articles that investigate facts and not just hype the spin, confuse people and promote ignorance. And a few less straw man arguments by journalists claiming to be skeptical wouldn’t go amiss. Skeptics seek the facts to support an argument and promote critical thinking, aspects sadly lacking in this present debate. However for those wanting such a debate, then please come along to the Skeptics National conference in Adelaide in October where this very topic will be debated on the Sunday morning session.”
Now it’s fine to cut the letter and with hindsight what was cut will be going straight back to them because I find out today, 1 week later, it would appear Chris has a bee in his bonnet about this issue. And the straw man arguments return which is really sad because I remember the long past days of decent journalism.
Without further ado here is his rebuke:
Sceptics can’t deny the facts
- Skeptics SA accused me of getting my climate change facts wrong last week. However, the U.K.’s Hadley Centre shows none of the past 10 years has been as warm as 1998. Sure, the centre claims there is still evidence of a warming trend, albeit reduced from a decade ago. But it confirms that each of the past 10 years has been cooler than 1998.
- The Skeptics SA letter also referred to scientific consensus. We often hear this term now but science is not about consensus, it is about objective fact.
Another reader asks what more Australia could do to reduce carbon emissions. If we were serious, the first thing we would do is lift our ban on uranium exports to India.
Just to restate what happened, someone made a claim, it was factually wrong and they were corrected. I would have thought that’s the end of the matter, lesson learnt. As a skeptic I certainly was not denying the facts. And no-one is claiming that 1998 was not a hot year. Is stating that “Sceptics (sic) can’t deny the facts” suggesting that skeptics have denied the facts? Who knows. Perhaps Chris is claiming he is now a skeptic and that even he can’t deny the facts anymore? That would be reassuring however it is again misleading to state something out of context and to ignore the factual reason which is given by the Hadley Centre. To get a view of the temperature over the past few years, here’s the graph showing this.
The temperature spike at 1998 can clearly be seen. And it’s explanation, which Chris does not even hint at:
1998 saw an exceptional El Niño event which contributed strongly to that record-breaking year. Research shows that an exceptional El Niño can warm global temperatures by about 0.2 °C in a single year, affecting both the ocean surface and air temperatures over land. Had any recent years experienced such an El Niño, it is very likely that this record would have been broken. 2005 was also an unusually warm year, the second highest in the global record, but was not associated with El Niño conditions that boosted the warmth of 1998.
A picture says a thousand words and anyone can see that 1998 is an usual year. It is also apparent that what the Hadley Centre claims about increasing temperature is also correct. The fact that 1998 was a record breaking year does not invalidate the statement from the Hadley Centre that the average temperature is increasing. And before people jump in with “but the last 6 years hasn’t warmed” I’d just like to point out we are not denying this. We’d also not support it either because the error bars clearly show the error measurement is much larger that what we are looking for. The correct position is “we don’t really know”. Perhaps some of the readings were wrong, perhaps there were other things happening such as what happened in 1960’s with increased aerosols and particulates, who knows. That’s why we have error bars on good graphs, so we know how good the data is and don’t make incorrect claims.
This leads into Chris’s second point, that about consensus and his incorrect belief it has no place in science. If the world was perfect, measurements never had errors, all factors and processes were well known, humans were perfect and generally the whole place was painted in black or white then this would be a valid statement. However in the reality based world that science lives in we know this isn’t correct.
When you make a measurement there is error and variation. Sometimes there are competing explanations for observations. Sometimes the world is complex and it’s not apparent exactly what is influencing what and what the processes are. And sometimes people have differing points of view and different backgrounds that enable them to look at the same data but draw different conclusions. However this does not mean no claims can be made, as many post-modernists are want to do, or that nothing can be said until everyone totally agrees. There is a misconception in the general public, and this applies to nearly all journalists, the vast majority of whom have no background in science, that science gathers pure unambiguous facts and then make a dogmatic decree of the new knowledge gained. This might be great for depicting a scientist for Hollywood but reality is different. Vastly different.
Actual science involves the rather more nebulous concept of supplying the best explanation for the available evidence. There is no place for dogmatic belief, unlike in religion where maintaining the status quo and existing faith based knowledge is crucially important. The “best explanation” involves many scientists agreeing that a conclusion can be drawn from the available body of evidence and, shock, horror this is usually done in a via consensus. Now some people might suggest the data is not accurate enough, or not enough data has been collected, or that it is not representative or a hundred reasons why they personally cannot accept the proposed conclusion. That’s fine and science allows for dissent, in fact it strives on dissent. However when the vast majority of scientists agree on something then that’s good enough. If someone brings along more,better or different evidence and it’s convincing and of suitable quality then the consensus will change. It would be lovely to live in a world of unambiguous objective fact but unfortunately that world only exists in the minds of those ignorant to the scientific method, those used to living in a world of political decree and religious dogma.
And for a recent discussion about long term trends, see this article I wrote a while ago.