Ward explains that the greatest extinction event in Earth's history, 250 million years ago, killed roughly 90% of all species and was caused not by an asteroid but by massive volcanic activity in Siberia that flooded the atmosphere with carbon dioxide. Ward describes the alarming parallels to current conditions, noting that Mount Kilimanjaro is losing its snow 15 years ahead of predictions.
Ward addresses the methane threat lurking in ocean sediments and Arctic permafrost, confirming the scientific concern that warming could trigger catastrophic releases. He discusses computer climate models projecting 1,000 parts per million of atmospheric CO2 within 100 to 200 years, a level that would transform Washington State into a tropical environment with palm trees and malaria. Ward suggests that intelligent species inevitably damage their planets through technological advancement, potentially explaining why the search for extraterrestrial intelligence has found silence.
Key Moments
The Great Dying wasn't an asteroid: Ward says he and many colleagues went looking for evidence that the Permian extinction - which wiped out 90% of all species 250 million years ago - was caused by a bigger asteroid than the one that killed the dinosaurs, and to their surprise found no impact evidence at all.
Siberian Traps: a quarter billion years ago, no factories: Ward identifies the cause of the Permian extinction as the largest volcanic event in planetary history - the Siberian Traps, lava covering a quarter of Siberia from massive fissures - which dumped enough CO2 to warm the planet roughly 10 degrees C and crash atmospheric oxygen.
Methane bubble: China disappearing in an instant: Ward confirms Whitley Strieber's concern about seafloor methane and cites Northwestern chemical engineer Gregory Riskin's published scenario in which enough methane could come out of the Black Sea as a single bubble that, struck by lightning, would behave like a fuel-air bomb capable of erasing China in an instant.
Lake Nyos: 2,500 dead in two hours: Ward describes the 1986 Lake Nyos disaster in Cameroon - a volcanic lake with CO2 trapped in bottom sediment that overturned in a single night, releasing a semi-liquid CO2 cloud that killed 2,500 people and 10,000 cattle within two hours - and warns the same oceanography applies to today's methane-loaded oceans.
Of 15 mass extinctions, 14 were CO2: Ward states the bottom-line statistic from his research: of roughly fifteen mass extinctions in Earth's history, only one can be tied to an asteroid impact - the other fourteen all appear connected to rapid rises in carbon dioxide.