In September, the Intergovernmental Panel on Climate Change (IPCC), among the most conservative scientific organizations on Earth, issued a report concluding that global warming is irreversible without geo-engineering.
Meanwhile, in December, the U.S. National Academy of Sciences announced that gradual change of the climate is not guaranteed: “The history of climate on the planet — as read in archives such as tree rings, ocean sediments, and ice cores — is punctuated with large changes that occurred rapidly, over the course of decades to as little as a few years.”
Indeed, Earth has witnessed a five-degree Celsius rise in global-average temperature during a span of 13 years.
Writing for the Arctic Methane Emergency Group, John Davies concludes: “The world is probably at the start of a runaway Greenhouse Event which will end most human life on Earth before 2040.” Davies considers only atmospheric carbon dioxide concentration, not the abundant self-reinforcing feedback loops triggered on the climate-change front.
Considering only one feedback loop among many, methane release from the Arctic Ocean is expected to increase global-average temperature by more than 4°C by 2030 and 10°C by 2040, according to Sam Carana’s research (see especially Image 24).
Humans have not occupied Earth at 3.5°C above baseline. If this seems problematic to you, I believe you’re paying attention.
— Guy McPherson, Transition Voice