Nicholas Stern, co-chair of the Global Commission on the Economy and Climate, which produced the study, said: “Current economic models fail to capture both the powerful dynamics and very attractive qualities of new technologies and structures [that reduce carbon]. Thus we know that we are grossly underestimating the benefits of this new growth story. Further, it becomes ever clearer that the risks of the damage from climate change are immense, and tipping points and irreversibilities getting ever closer.”
The existence of tipping points – thresholds of temperature beyond which certain natural processes become irreversible, such as the melting of permafrost, which may release the greenhouse gas methane and create runaway warming effects – is a key concern of many climate scientists. The faster emissions rise, the sooner we may unwittingly pass some of these key points.
For all these reasons, the IPCC’s special report comes at a crucial point. Scientists and economists have warned that if the world cannot shift course within the next few years, the consequences will be dire, as new infrastructure built now – in energy generation, transport and the built environment – will be made either to low-emissions standards or in the high-emissions habits of the past. As the IPCC’s next comprehensive assessment of climate science will not be available until 2021, this year’s report will be vital in shaping policy.