A key alarmist premise is that recent changes in temperature are “unprecedented” thus proving that we broke nature so we own it and must make good. The difficulty is that before the modern thermometer era we have only proxy data on past temperature, and the proxies rarely capture short-term fluctuations. The fabled ice cores, useful as they are for the last 800,000 years or so in the case of Antarctica, and around 130,000 years in Greenland, suffer the key weakness that the air bubbles that encode ancient data take centuries to seal. But (h/t Matthew Wielicki) real scientists try to work around limitations on data rather than pretending they don’t exist. Like this new study of “Dansgaard-Oeschger Events” using fossil pollen records to confirm that indeed fast major temperature changes are nothing new or, therefore, artificial. And by fast, we’re talking 10-16˚C in 50 to 200 years. Way bigger than anything we’ve seen or are about to, let alone could cause even if we wanted to.
For those not in the terminologically obscure know, D-O events are sudden rapid climate fluctuations that have been known for some time to occur during the last glaciation, contrary to dogma. (Like “Bond events“ during the Holocene.) So all this study does, or what it does, is to extend the investigation from Greenland to the globe. But in doing so it confirms what was already known, that these claims of modern conditions being unprecedented were as wrong as they were shrill. As, we might add, does Willis Eschenbach’s graph of the fluctuating rate of warming acceleration in the last century, with the 1920s more dramatic than the 21st century. And at some point if enough central assertions of a theory are shown to be false, the theory collapses. Or tears off the lab coat to reveal the DogmaPerson supersuit beneath.
To survive in state-funded climate science, you cannot of course talk in such a blunt manner, especially if say you were hoping to be published by Copernicus. So the paper puts the “Workers of the world, unite” sign right in the window, starting its abstract:
“Dansgaard-Oeschger (D-O) warming events are comparable in magnitude and rate to the anticipated 21st century warming. As such, they provide a good target for evaluation of the ability of state-of-the-art climate models to simulate rapid climate changes.”
Riiight. Rapid natural changes let us simulate rapid man-made ones. But never mind.
Do mind that we’re dealing with a double proxy in the form of a “plant-available moisture index” that uses fossil pollen to judge plant patterns and plant patterns to judge atmospheric CO2 concentrations, via water use efficiency. Which does rather limit the precision. But within those limits, which we stress because the result seems to confirm our views and it is not good science to be more skeptical of proxies we dislike than those we like, the simple finding is that there were plenty of cases in the past 50,000 years when temperatures shot up or down with striking rapidity. (And also that the Northern and Southern Hemispheres seem to have been in “anti-phase” if you care.)
To be clear, it only proves a negative. The fact that there have been other, natural warmings as fast and large as that of the 20th century does not establish that the 20th-century warming was natural, only that it could have been. (As for the projected 21st-century warming, well, so far it’s just an artefact inside a computer.) But by proving that it was not necessarily man-made it refutes the arguments of fanatics who have cited it as unprecedented and therefore demonstrably man-made. It would even embarrass them, if they were capable of such.
No, wait. It proves another negative. Because these warmings were not caused by CO2 at all. As Wielicki puts it:
“This pattern is not what a simple ‘CO₂ knob’ model would predict. It is what circulation reorganization looks like.”
Circulation reorganization being changes in air or ocean currents. The sort of thing Javier Vinós has been pointing to while orthodoxy keeps chanting “CO2 CO2 CO2.”
In this regard it proves a positive as well. It proves that people who still cling to the “Enhanced CO2 Hypothesis” now do so despite evidence not because of it.
