From carbon emissions to sea-level rise to global warming, the rate and extent of all the major indicators of climate change are in unprecedented territory, over 60 leading scientists cautioned on Thursday.
Greenhouse gas emissions due to the combustion of fossil fuels and deforestation reached a record level in 2024 and averaged, across the decade, a new record 53.6 billion tonnes annually — or 100,000 tonnes a minute — of CO2 or an equivalent in other greenhouse gases, they wrote in a peer-reviewed update.
The Earth’s surface temperature in the previous year passed 1.5C above pre-industrial levels for the first time, and the extra CO2 human civilisation can emit with a two-thirds probability of remaining below that level in the long term — our 1.5C “carbon budget” — will be depleted within two years, they estimated.
Investment in clean energy outpaced investment in oil, gas and coal last year two-to-one, but fossil fuels account for more than 80 per cent of global energy consumption, and growth in renewables still lags behind new demand.
Enshrined in the 2015 Paris climate agreement as a target to strive for, the 1.5C threshold has since been scientifically endorsed as required to avert a horribly climate-beset planet. The strict limit on warming to which almost 200 countries signed up was “well below” two degrees, generally understood to be 1.7C to 1.8C.
With the 1.5C level now set to be crossed in the next few years, “we are already in crunch time for these higher levels of warming,” co-author Joeri Rogelj, a professor of climate science and policy at Imperial College London, said in an interview with reporters in a briefing. “The next three or four decades is pretty much the timeline over which we expect a peak in warming to occur.”
‘The wrong direction’
No less troubling than record temperatures and carbon outputs is the accelerating rate at which these and other climate markers are changing, the research, published in Earth System Science Data, finds.
Human-caused warming accelerated during the past decade at a rate “unprecedented in the instrumental record”, and significantly higher than the 2010-2019 average recorded in the UN’s latest Intergovernmental Panel on Climate Change (IPCC) report, in 2021. The new data — under the same scientists using practically the same techniques — are meant as an authoritative if unofficial revision of the standard IPCC reports that form the basis of global climate diplomacy.
