Humanity has less than three years to halt the rise of planet-warming carbon pollution, UN climate experts warned Monday, with any delay to peak greenhouse gas emissions likely to result in smashing through warming targets.
“We are at a crossroads,” said IPCC chief Hoesung Lee. “The decisions we make now can secure a liveable future. We have the tools and know-how required to limit warming.”
Reports from the Intergovernmental Panel on Climate Change are considered the most authoritative assessments of the state of global warming, its impacts and the measures being taken to tackle it.
Governments agreed in the 2015 Paris accord to cap global warming at 1.5 degrees Celsius this century in order to avoid a climate catastrophe, but many experts say doing so will require drastic cuts to greenhouse gas emissions.
How to keep a world addicted to fossil fuels liveable
The UN Intergovernmental Panel on Climate Change on Monday presented options for slashing greenhouse gas emissions and extracting CO2 from the air in order to avert catastrophic climate change.
Burning fossil fuels and deforestation have heated Earth’s surface 1.1 degrees Celsius above mid-19th century levels, and nations have pledged under the 2015 Paris Agreement to cap global warming at “well below” 2C, or 1.5C if possible.
Here are some of the landmark 2,800-page report’s key findings:
Peak emissions by 2025
Failing to sharply curb greenhouse gas emissions beyond national pledges before 2030 would put a 1.5C world “beyond reach”.
Current carbon-cutting policies would lower emissions only slightly by 2050, leading to global warming of 3.2C by century’s end.
Even a 2C cap would become hugely challenging: annual emissions would need to decline by 1.5 billion tonnes of CO2 or equivalent gases (GtCO2-eq) every year from 2030 to 2050 – roughly the same annual decrease as in 2020 when Covid lockdowns paralysed the global economy.
To keep global temperatures below 1.5C, 2C or even 2.5C, emissions must peak before 2025.
But in 2021 emissions recovered to record pre-pandemic levels of more than 40 billion tonnes of CO2 (40 GtCO2).
At 2019 levels of emissions, Earth’s “carbon budget” for a two-thirds chance of staying under the 1.5C threshold will be used up within eight years.