Global emissions must peak in just three years to stay below 1.5°C

Adam Vaughan is a writer.

The world's target of holding global warming to 1.5 degrees C is still within reach, but humanity must peak its emissions within three years to avoid breaching it.

The window for staving off dangerous warming has shrunk due to our past failures to act, according to a report by the Intergovernmental Panel on Climate Change. It found that the world can afford to emit 500 billion tonnes of carbon dioxide from 2020 onwards for a 50 per cent chance of keeping the temperature from rising.

Simulations show how societies can meet the tight carbon budget by peaking emissions by 2025. At a time when many governments are preoccupied with the war in Ukraine and the ongoing coronaviruses, it would require a gargantuan political effort to limit global emissions.

The authors of the report say that coal use must drop 95 per cent by 2050, oil must drop 60 per cent, and gas must drop 45 per cent. A substantial amount of fossil fuels unburned and up to $4 trillion of fossil fuel infrastructure would be left if the Paris Agreement is not met.

The report shows that governments aren't doing enough. The world will likely exceed the 1.5 degree C threshold by this century, taking into account pledges before last November's COP26 climate summit.

Read more: After deadly floods, can Germany adapt to its climate future?

The reasons for hope were found by the IPCC. At least 18 countries have reduced emissions for more than a decade. The costs of solar energy, wind energy, and batteries used in electric cars and energy storage fell between 2010 and 2019.

Emissions reductions will be needed across all sectors, using a mix of renewable energy, carbon capture and storage (CCS), lower energy demand, better energy efficiency and a huge ramp-up of ways to remove CO 2 from the atmosphere. The amount of modelling needed to reach climate goals was found to be far below deployment of CCS.

The role of behavioural change on emissions reductions was considered for the first time by the Intergovernmental Panel on Climate Change. Pete Smith, a member of the Intergovernmental Panel on Climate Change, says that the way we move around, the way we eat, the way we generate energy, everything needs to change.

Lowering emissions will be cheaper than global GDP growth, according to the Intergovernmental Panel on Climate Change.

The first and second reports were about causes of climate change and the third was about the impacts. The new report was signed off by governments after the launch was delayed.

The delay was caused by requests from Saudi Arabia, India, and the US over language on long-term fossil fuel use, as well as a row between the US and China over financing to act on climate change, delegates told New Scientist.

The report should serve as a reminder to governments to deliver on their promises to deliver new and stronger national climate plans this year, according to the president of COP 26.

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