In Australia, in the midst of a record-breaking global heat wave, a recent international study presented a terrifying worst-case scenario: that hothouse Earth conditions are likely to prevail even if the world meets the carbon reduction levels of the Paris Agreement.
Lead author Will Steffen from the Australian National University and Stockholm Resilience Centre said, “Human emissions of greenhouse gas are not the sole determinant of temperature on Earth. Our study suggests that human-induced global warming of 2°C may trigger other Earth system processes, often called feedbacks, that can drive further warming – even if we stop emitting greenhouse gases.”
Feedback processes include the release of methane from Arctic ices melted by high ocean temperatures, reduction of North American snow cover and Amazon rainforest dieback. These processes compound the inherent difficulty of studying the climate on a global scale, and substantial disagreements exist between models predicting the future of climate change.