Climate change, extinctions signal Earth in danger zone: study

Climate change and high rates of extinctions of animals and plants are pushing the Earth into a danger zone for humanity, according to an international team of 18 experts. The team expanded on a 2009 report about “planetary boundaries” for safe human use, and also sounded the alarm about clearance of forests and pollution from nitrogen and phosphorus in fertilisers. After assessing nine boundaries, including freshwater use, ocean acidification and ozone depletion, the report defined climate change and loss of species as two core areas of concern.

If temperature affects economic growth rates, society could face much larger climate damages than previously thought. This would justify more stringent mitigation policy.

Delavane Diaz, co-author of the Social Cost of Climate Change report from Stanford University

Rising concentrations of carbon dioxide, the main greenhouse gas, are about 397 parts per million in the atmosphere, above 350 ppm that the study set as the boundary for safe use. Almost 200 governments will meet in Paris in late 2015 to try to agree a deal to limit global warming to avert floods, droughts, heatwaves and rising sea levels blamed on rising emissions of greenhouse gases.

Science Climate change