Quanta Magazine reports that all scientific doubt has been removed about massive global warming. The one that caused the extinction of… the Paleocene. Specifically, a huge plume of lava 60 million years ago bursting forth from the seabed that reshaped the northern hemisphere, heated up the atmosphere and the oceans and caused the Paleocene-Eocene Thermal Maximum (PETM). Which has “parallels to today’s climate change” except the part where it took thousands of years, wasn’t man-made, and didn’t cause mass extinctions. But see carbon dioxide waaaaa.
The events the article describes are fascinating, lurid and more than a lot scary. Around 60 million years ago when the “Iceland plume… pierced the bottom of the North Atlantic Ocean, lava spurted across Scotland, Ireland and Greenland, scabbing into spectacular columned landscapes like the Giant’s Causeway in Northern Ireland and Scotland’s Fingal’s Cave.” Then, four million years later “a second gigantic pulse of hot mantle rock… swelled under the seafloor and lifted a wide region of ocean floor between Greenland and Europe into the air, forming a temporary land bridge connecting Scotland and Greenland.” Then as it cooled it “cooked organic matter” and released methane and CO2. Kaboom!
What’s the connection with the formerly mysterious PETM, a sudden temperature spike that “has preoccupied climate scientists since its discovery in the early 1990s”? The article says it was “suspiciously close in time”.
Well, yes. And while correlation is not causation something as dramatic as the PETM probably has a dramatic cause and this one certainly qualifies. But the similarities to present day events are not nearly as compelling. For instance those two vast blasts of lava. And that the PETM saw temperatures rise by around 5˚C over thousands of years. (Wikipedia says 6 degrees over 20,000 years.) Which not even Michael Mann is predicting now. Sober analysts aren’t talking about 5 degrees and nobody’s talking about millennia. Some scare that time-scale would make.
The article goes on to discuss the resulting “intense downpours” on land “while ocean acidification and heat drove many marine species extinct. Many land animals went extinct as well and were replaced by dwarf species. The Arctic had alligators, giant tortoises, and vegetation typical of Florida today, and sea levels were around 300 feet higher than now.” So very much like what the modern world is not.
Besides, as the famously non-skeptical Skeptical Science site grudgingly admits, “there was no vertebrate mass extinction”. Whereas if temperatures rise by 1.5 degrees in the next century we’re told everything nice from coral to polar bears will buy the drought-ravaged farm.
Here’s what National Geographic had to say about the PETM a few years back: “During the dawn of the “Age of Mammals”, around 56 million years ago, the global temperature rapidly stabbed upwards. In about 100,000 years temperatures rose over 40 degrees Fahrenheit.” Sorry. Could you say that again? The “dawn of the ‘Age of Mammals’”? Do you mean to tell us this temperature surge, which was far bigger and longer than the IPCC’s worst-case scenario for 2100, saw a proliferation of new life? Including the primates known as us?
The bottom line is that a catastrophic event that created a land bridge from Greenland to Scotland caused a warming over thousands of years that didn’t make the Earth less habitable. If anything it made it more so. Besides which humans are a long way from picking up the ocean floor, hurling it across vast distances on a fiery chariot of lava, then cooking it. And you only say it was the resulting CO2 that did it because you knew it ahead of time. Indeed, journalists have been saying scientists were saying the PETM was “the best analog we have to the climate change that is happening today” since a comet supposedly smacked into the Earth and, what do you suppose, “In the blink of an eye, geologically speaking, thousands of gigatons of carbon were released into the atmosphere.”
So the PETM is exactly like today in that humans weren’t causing a climate disaster either time. Otherwise totally different.