A climate paper published last July has been hyped up to apocalyptic noise levels by climate scientists and the news media despite new research findings having debunked their main claim.
These alarmist media reports ignore that new geological evidence published in recent weeks shows that the Permian-Triassic mass extinction 250 million years ago occurred during an ice age and not during a period of global warming.
Earth has known several mass extinctions over the course of its history. One of the most important happened at the Permian-Triassic boundary 250 million years ago. Over 95% of marine species disappeared and, up until now, scientists have linked this extinction to a significant rise in Earth temperatures. But researchers from the University of Geneva (UNIGE), Switzerland, working alongside the University of Zurich, discovered that this extinction took place during a short ice age which preceded the global climate warming. It’s the first time that the various stages of a mass extinction have been accurately understood and that scientists have been able to assess the major role played by volcanic explosions in these climate processes. This research, which can be read in Scientific Reports, completely calls into question the scientific theories regarding these phenomena, founded on the increase of CO2 in the atmosphere, and paves the way for a new vision of Earth’s climate history.
A technique founded on the radioactive decay of uranium.
Researchers worked on sediment layers in the Nanpanjiang basin in southern China. They have the particularity of being extremely well preserved, which allowed for an accurate study of the biodiversity and the climate history of the Permian and the Triassic. “We made several cross-sections of hundreds of metres of basin sediments and we determined the exact positions of ash beds contained in these marine sediments,” explained Björn Baresel, first author of the study. They then applied a precise dating technique based on natural radioactive decay of uranium, as Urs Schaltegger added: “In the sedimentary cross-sections, we found layers of volcanic ash containing the mineral zircon which incorporates uranium. It has the specificity of decaying into lead over time at a well-known speed. This is why, by measuring the concentrations of uranium and lead, it was possible for us to date a sediment layer to an accuracy of 35,000 years, which is already fairly precise for periods over 250 million years.”
Ice is responsible for mass extinction
By dating the various sediment layers, researchers realised that the mass extinction of the Permian-Triassic boundary is represented by a gap in sedimentation, which corresponds to a period when the sea-water level decreased.
The only explanation to this phenomenon is that there was ice, which stored water, and that this ice age which lasted 80,000 years was sufficient to eliminate much of marine life.