Restricting global warming to 1.5˚C above pre-industrial levels will require “rapid and unprecedented changes in all aspects of society”, a landmark report from the Intergovernmental Panel on Climate Change (IPCC) has warned today.
It outlines how global warming of 2˚C would cause sea levels to rise by 10cm higher than under a 1.5˚C scenario by the end of the century, while coral reefs would be completely wiped out.
But achieving the 1.5˚C target will require transitions in land, energy, industry, buildings, transport and cities, with carbon emissions falling 45% by 2030 and reaching ‘net zero’ by 2050.
Coal would need to be phased out entirely by then, with renewables making up half of the global energy mix.
"Limiting warming to 1.5°C is possible within the laws of chemistry and physics but doing so would require unprecedented changes," said Jim Skea, IPCC Working Group III co-chair.
With 6,000 scientific references and 91 authors from 40 countries, the IPCC report will play a key role informing world leaders when they review the Paris Agreement at December’s COP24 conference in Poland.
Along with rising sea levels and vanishing coral reefs, the report forecasts an Arctic Ocean free of ice at least once every decade with global warming of 2˚C, compared with once per century under a 1.5˚C scenario.
It highlights how exceeding the 1.5˚C threshold would necessitate a greater reliance on techniques that remove CO2 from the air, but warns that these methods are unproved at large scale and may carry risks to sustainable development.
The report outlines the pathways available to limit global warming to 1.5˚C, what it would take to achieve them and what the consequences would be, with the next few years “probably the most important in our history”.
Climate Analytics SIDS climate advisor, Rueanna Hayes, said the findings suggest countries must redouble efforts to reduce emissions under their Nationally Determined Contributions (NDCs).
“Government commitments are far from sufficient and will not achieve the Paris Agreement’s warming limit,” she said. “This report provides the scientific grounding to kick this off in Katowice in support of the push for more ambitious NDCs to be submitted by 2020.”
Image credit: iStock