This communication concerns some misinformation that Herald Sun columnist Andrew Bolt has been publicising since late last week. Bolt claims his “seven graphs” from reputable sources prove conclusively that the world is cooling not warming and Arctic ice is not thinning.

He first presented it in his blog last Thursday and then on Insiders on ABC on Sunday he heavily promoted it and aggressively challenged Annabel Crabb to dispute these findings, all, of course, to attack the government’s Green Paper and Garnaut Report. Then on Monday he ran another related story as a follow up (Arctic Ice) and Tuesday another follow up. Being something of an agnostic on the topic myself I thought it was worth looking at, but was then appalled at how he has totally misinterpreted the graphs he presents.

Without even verifying the source or content of these graphs but just taking them at face value, I believe that any scientist or reasonably intelligent person would agree with my statements. If a scientist presented this at a conference he would be laughed at or met by stunned, embarassed silence. Let’s look at Bolt’s graphs…

Andrew Bolt apparently is basing his argument — that the world really is cooling rather than warming — on a short blip in the data around January 2008. But the logical comparison is shown by the blue ovals which very roughly centre on the average for the time periods (note the ovals are identical in size); it is obvious the recent period is up to 0.3 degrees warmer. In his graph 2, the same data is plotted but now extending back to 1979 — it shows even more clearly the average warming over the period 1999-2007. Note that in this second graph which extends to June 2008 the January 2008 low-point is less obvious!

This is Andrew Bolt’s second graph that he uses to try to claim the world is cooling rather than warming. He does this by using a blip of data spanning a tiny sliver of time as represented on these graphs (the descending line to the far right, which looks like the recurrent low point also seen in the 2004 and 2006 periods). But taking an average over the recent decade and the 1979-1997 periods a five year-old could tell Bolt that the former is obviously higher than the latter. Ignoring or correcting for the volcanic eruption (1992) or the El Nino (1998) events does not change this picture significantly. This may well not be enough to support a global warming hypothesis but it very unambiguously does not support a recent cooling.

This is Andrew Bolt’s third graph that he uses to try to claim the sea-level is falling rather than rising! Given the impressive upward trendline over 15 years (I have not checked its origin or veracity) it is deeply mysterious how he comes to this conclusion. Is it that he interprets the incomplete 2008 data showing a downward blip (which I have highlighted in red, with questions marks)? Bolt needs to stick to journalism or something that doesn’t require any kind of logical interpretative skills.

Andrew Bolt bases his erroneous claim that Arctic sea ice is not thinning on two weeks of the most recent data for 2008 (highlighted in red on graph) and only in comparison to the same period in 2007; in fact the data confirm it is thinning. The US laboratory that provided this graph also claims: “According to scientific measurements, Arctic sea ice has declined dramatically over at least the past thirty years, with the most extreme decline seen in the summer melt season.” So, should we make broad sweeping conclusions from 2 weeks’ data or from yearly, or 20 years (1979-2000) or 30 years of data? 

I posted a comment in response to Bolt’s article (mine is one amongst over 500 comments from mostly appallingly ignorant ranters) — but of course I couldn’t post the graphs.

I think it is important that loud polemicists like Bolt spouting distorted nonsense need a counterbalance in the media.

Michael James is a Senior Research Fellow and Director for the Genome Variation Laboratory at the Queensland Institute of Medical Research. He is speaking as an individual and not on behalf of his institute.