Matt Ridley thinks global cooling – any cooling – is “not worth shivering about“. I agree and disagree. Matt says:
Valentina Zharkova of Northumbria University has suggested that a quiescent sun presages another Little Ice Age like that of 1300-1850. I’m not persuaded.
Actually, Zharkova thinks some cooling similar to that which occurred during the Maunder Minimum (1645-1715) may occur in the near future (2030 onwards) because of a possible approaching solar activity Grand Minimum, predicted by her mathematical model of solar magnetic fields. I am persuaded. The degree of cooling will be dependent on how right (or wrong) predictions of global warming based upon GCMs are. Currently, they’re not doing that well, having failed to anticipate the Pause, now only looking reasonable because of a ‘spurt’ in global warming caused by El Nino and a hitherto unexplained reluctance of the planet to cool significantly in 2017 (with a few very notable regional exceptions), despite a weak La Nina. But it has cooled of course, enough to leave the warming trend since 1979 in UAH satellite data unchanged at 0.13C/decade, which is significantly short of what climate models predicted for the lower troposphere. 2017 was the third warmest year since 1979, behind 2016 and 1998. So one year after the super El Nino year of 2016, it’s warm, but not as warm as it was in the previous super El Nino year of 1998, now 20 years ago. Hence no sign of runaway global warming, no sign of imminent cooling either. Boring.
But I’m not going to rattle on about a possible ‘Little Ice Age’ and what that might mean for the economy and food production and the poor sods who can’t afford to heat their homes even now courtesy of renewables zealots; I’d like to talk about proper Ice Ages (more correctly, glacials), which is what Matt Ridley talks about mainly, in The Times.
For his sin of discussing full blown glacials, and speculating when the next might be, Ridley is given a dressing down by two heavyweight intellectuals – namely, Dr. Emily Shuckburgh of the British Antarctic Survey and Professor Eric Wolff, FRS of the Dept of Earth Sciences at Cambridge. This is their indignant and arrogant letter to The Times:
As Paul points out on Twitter, first they are “absolutely sure” that anthropogenic GHGs have ‘broken’ the sawtooth-like cycle of Pleistocene glacials and interglacials and that this “finding” is “profound”, then they say GHGs “could” delay the inception of the next glacial way beyond when it is expected. Not exactly a shining example of temperance and even-handed scientific logic from two leading supposed experts in their field; in fact somewhat spiteful and evidently a carelessly and hastily thrown together dismissal of a person whose opinion and writings in general they probably have little respect for, being obvious members of the Konsensus.
I’m almost certain that Wolff & Shuckburgh’s “latest scientific results” equates to a 2016 Nature study by Ganopolski, Winkelmann and climate adviser to his Green Holiness Pope Francis, the notorious alarmist Hans Joachim Schellnhuber – Critical insolation–CO2 relation for diagnosing past and future glacial inception. The essence of this paper is as follows:
- Earth narrowly avoided the inception of a new glacial age just before the Industrial Revolution because CO2 levels were 40ppm above the threshold 240ppm
- Pre-industrial land use may have caused CO2 to be elevated, in which case not being well on the way now to a full glaciation is our fault.
- The Holocene, even without additional CO2 released by fossil fuels, will probably last another 50,000 years.
- Because of the burning of fossil fuels, the end of the Holocene is now delayed for an extra 50,000 years, meaning it won’t end for at least another 100k years.
So not only have we broken the cycle of approximate 100,000 year glaciations, followed by brief (tens of thousands of years) interglacials, but we’ve effectively terminated the Pleistocene Ice Age which started 2.6 million years ago – although purists will say that the Pleistocene Epoch ended 11,700 years ago, when the Holocene began. In honour of our “profound” geological impact over just 200 years, the Holocene has also ended in the minds of some and the Anthropocene has already begun, an epoch during which the poles will likely melt altogether, sea level will rise hundreds of meters and the Earth will be burned to a crisp by an unstoppable enhanced Greenhouse Effect.
It could have been so different. We could have been joyfully watching the advance of mile high ice sheets by now, covering much of North America and Europe, and celebrating the receding coastlines as sea-level dropped. No more Sandys and Harveys devastating vulnerable coastal cities, which would now be miles inland. Alas, ’twas not to be. I don’t know about you however, but the prospect of another 100,000 years of warmth and high CO2 doesn’t sound all that bad when compared to the alternative. Over such an enormous span, humanity would inevitably adapt, as indeed it would during a major glaciation, but I know which I would prefer. So does civilisation – it was unknown until the advent of the warm Holocene interglacial.
Ridley takes a slightly different view and accepts the inevitability of a major glacial period some tens of thousands of years from now – still hardly imminent, giving us plenty of time to adapt. He says:
That [Holocene] interglacial will end. Today the northern summer sunshine is again slightly weaker than the southern. In a few tens of thousands of years, our descendants will probably be struggling with volatile weather, dust storms and air that cannot support many crops.
For this he provoked the indignation and wrath of Konsensus scientists who are ‘absolutely sure’ that the Holocene won’t end, because we messed up the age old cycle by burning Epoch-busting fossil fuels. He also had the temerity to quote alternative research on glacial inception and termination which, rather than elevate CO2 as a main driver, along with Milankovich cycles, invokes CO2 but in a uniquely different manner – as plant fertiliser. He explains this research as follows:
Game, set and match to Milankovich? Not quite. The Antarctic ice cores, going back 800,000 years, then revealed that there were some great summers when the Milankovich wobbles should have produced an interglacial warming, but did not. To explain these “missing interglacials”, a recent paper in Geoscience Frontiers by Ralph Ellis and Michael Palmer argues we need carbon dioxide back on the stage, not as a greenhouse gas but as plant food.
The argument goes like this. Colder oceans evaporate less moisture and rainfall decreases. At the depth of the last ice age, Africa suffered long mega-droughts; only small pockets of rainforest remained. Crucially, the longer an ice age lasts, the more carbon dioxide is dissolved in the cold oceans. When the level of carbon dioxide in the atmosphere drops below 200 parts per million (0.02 per cent), plants struggle to grow at all, especially at high altitudes. Deserts expand. Dust storms grow more frequent and larger. In the Antarctic ice cores, dust increased markedly whenever carbon dioxide levels got below 200 parts per million (0.02 per cent), plants struggle to grow at all, especially at high altitudes. Deserts expand. Dust storms grow more frequent and larger. In the Antarctic ice cores, dust increased markedly whenever carbon dioxide levels got below 200 ppm. The dust would have begun to accumulate on the ice caps, especially those of Eurasia and North America, which were close to deserts. Next time a Milankovich great summer came along, and the ice caps began to melt, the ice would have grown dirtier and dirtier, years of deposited dust coming together as the ice shrank. The darker ice would have absorbed more heat from the sun and a runaway process of collapsing ice caps would have begun.
Heresy, I’m sure you will agree. APPCCG certainly agrees:
If that’s Shuckburgh and Wolff communicating science succinctly, then Mohammed was a born again Christian caught in a time warp. Who are the APPCCG I hear you ask? The All-Party Parliamentary Climate Change Group. Chaired by Caroline Lucas. Enough said. Emily Shuckburgh proudly retweeted the tweet above, no doubt very pleased with herself for countering climate fiend Ridley’s attempt to misinform the world about ice ages and global cooling.
In a second post, we’ll examine the competing theories on what really causes glacial periods to come and go in regular fashion and we’ll see just how ‘certain’ it is that they’ve gone the way of the dinosaurs – well, at least for the next 100,000 years anyway. We’ll also look at when we can realistically expect the Holocene to end, assuming CO2 is not the dreaded Thermageddon Molecule.