The carefully cultivated cocoon of ignorance over at New Zealand’s own tiny corner of the climate crank echo chamber has been glinting in the harsh light of reality in recent weeks, as a number of climate realists (that is, people who have a realistic appreciation of what climate science is all about, not cranks attempting to purloin that term) have taken to bringing uncomfortable facts to the commentary under Richard Treadgold‘s strange little posts. It’s been a most amusing sight, watching the blizzard of misdirection and misunderstanding attempting to counter persistent reality. But Treadgold, bless his possum-merino socks, is undaunted and recently addressed this year’s dramatic Arctic sea ice melt with the determined insouciance of one terminally disconnected from reality.
Why does everyone feel guilty about the disappearance of the Arctic ice? All it proves is a bit of warming; it most certainly does not prove a human cause for that warming.
As seasoned Treadgold watchers might expect, it gets worse…
If people only stopped for a moment and thought clearly, they would see no evidence in the mere melting ice of a human hand warming it.
Stopping for a moment, and thinking clearly, we can see that there is clear evidence of rapid warming in the Arctic region, accompanied by a strong decline in the surface area, extent and volume of the sea ice, at a time when the planet as a whole is warming because of a rapid build up of greenhouse gases in the atmosphere. The Arctic is expected to warm rapidly — that’s what the modelling suggests, and that’s what the observations show. However, Treadgold routinely denies that there’s been any global warming at all for the last 15 years — a trope of his I conclusively dealt with in these two posts earlier this year. To meet the need for some sort of internal consistency in his world view he therefore has to deny the obvious.
But obvious to the rest of us it is, as this recent paper by Notz and Marotzke demonstrates:
The most likely explanation for the linear trend [in sea ice decline] during the satellite era from 1979 onwards is the almost linear increase in CO2 concentration during that period.
Never mind. Treadgold now dons his industrial grade blinkers/blinders/welders goggles/rose-tinted glasses:
For if such evidence was detectable at the North Pole, it would be equally detectable at the South. But in Antarctica, evidence of human warming is so completely absent that the place is cooling.
The Antarctic peninsula is one of the fastest warming places on the planet. Ice shelves have crumbled and retreated, glacier mass loss has increased, and there are clear signs that the continent as a whole is losing ice mass.
It is true that the majority of Antarctica is not warming as fast as the Arctic, but that comes as no surprise. Models have projected slower warming down south, and the effects of the ozone hole have acted to slow that down even further. But for those who are prepared to look, the reality of warming is all too obvious1.
Finally, what possible harm could it cause? Since it’s happened naturally before, there’s no cause for concern.
And so to Treadgold’s closing paragraph, and the reason I bothered to write this post. Based on his motivated rejection of the evidence, he asserts there’s no cause for concern. This is nonsense of the first order, and here’s why.
The last time there may have been similar amounts of sea ice in the Arctic would have been in the immediate aftermath of the last ice age, about 9,000 years ago, during what’s known as the Holocene climatic optimum. The world was a very different place then, the causes of the ice reduction were different, and there wasn’t much in the way of advanced civilisation around. We can draw no reassurance from the state of the Arctic during the Holocene climatic optimum.
The current reduction in Arctic sea ice should be a matter of grave concern to us all, as this recent guest post from the founder of the Arctic Sea Ice blog argued persuasively2. The ice is acting as a bellwether for the planetary scale changes we have in store — but it’s more than that. It is itself a change in the northern hemisphere climate system, and it is already having impacts on the weather and climate being experienced all round the Arctic and down into the middle latitudes3.
What’s worse, even conservative projections for the likely timescales involved in moving to ice-free summers fall near to or within the 30 year climate commitment4, which means that ice-free summers are — literally — inevitable.
What that means for northern hemisphere climate is currently unknown. There are intriguing hints that Britain’s recent run of dismal wet summers might be related to changes in the Arctic, and recent sharp cold spells in winters in Europe and North America could also be the result of changes in atmospheric dynamics caused by the loss of ice. Unfortunately, the climate models we rely on to peer into future possibilities are not tracking Arctic ice loss well, and therefore can’t offer much help on what this means for the rest of the system.
That’s real uncertainty, and it’s dangerous. No amount of ill-founded and ignorant handwaving by people who reject the basic evidence will make it go away. Treadgold and his ilk, by ignoring the obvious and campaigning on that basis, are helping to make matters worse. For that, history will judge them harshly. I’ll pre-empt history, and express my utter contempt for the hubris that raises ignorance above knowledge, and prefers ideology to evidence.
- For a nicely nuanced look at the recent data, see this Eric Steig article at RealClimate. [↩]
- And see this Scientific American blog post for more. [↩]
- See here for a discussion of what’s going on by Jennifer Francis, a leading researcher in the field. [↩]
- The time it takes for the ocean/atmosphere system to reach initial equilibrium after greenhouse gas levels stabilise. [↩]