World on course for 2.5-2.9°C temperature rise: UN

Global temperatures are set to rise between 2.5-2.9°C above pre-industrial levels, unless countries "step up action and deliver more than promised" in their climate plans, the UN Environment Programme (Unep) found in its latest emissions gap report.

Predicted emissions for 2030 must be cut by between "at least" 28-42pc, compared to current policy scenarios, to align with Paris agreement goals of 2°C and 1.5°C, respectively, Unep found. The Paris agreement, which has almost 200 signatories, seeks to limit global warming to "well below" 2°C above pre-industrial averages and preferably to 1.5°C.

The report, Broken Record, found that if efforts on mitigation - cutting emissions - "implied by current policies are continued at today's levels", global warming will rise to 3°C above pre-industrial temperatures in this century. If countries' unconditional climate plans are followed, the temperature rise would be around 2.9°C and fully implemented conditional plans would lead to a temperature limit of 2.5°C. Unconditional climate plans are those a country can achieve without external financial support, while conditional plans include targets dependent on some level of external support. The likelihood of hitting the 1.5°C goal is 14pc, in the most optimistic scenario, Unep said.

If all conditional climate plans and long-term net zero commitments were met, it would be possible to limit warming to 2°C, but "net-zero pledges are not currently considered credible", Unep said. G20 countries - responsible for 76pc of emissions - are not reducing them at a pace aligned with their net zero targets, it added.

There has been some progress on policy since the Paris agreement was signed in 2015, "but significantly ramping up implementation in this decade is the only way to keep the window open" for the 1.5°C temperature goal "without significant overshoot", Unem said. "The world is witnessing a disturbing acceleration in the number, speed and scale of broken climate records", it added.

September was the "hottest recorded month", with global average temperatures 1.8°C above pre-industrial levels. There were 86 days over January-October recorded with temperatures over 1.5°C above the pre-industrial average, Unep found. "The world is setting alarming emissions and temperature records", Unep said. Global greenhouse gas (GHG) emissions rose by 1.2pc from 2021-22, to hit a new record of 57.4bn t/CO2 equivalent (CO2e). CO2 emissions from fossil fuel combustion and industrial activity contributed the most to the overall increase, accounting for around two thirds of current GHG emissions, according to Unep.

High-income countries will need to take "more ambitious and rapid action" and provide financial and technical support to developing countries, to limit warming, the report found. It warned that the coal, oil and gas extracted over the lifetime "of producing and planned mines and fields" would equal emissions of more than 3.5 times the carbon budget available to cap warming at 1.5°C and would amount to "almost the entire budget available for 2°C".

Any further delay to "stringent" global emissions reductions will lead to heavier reliance on carbon removal technologies (CDR). Scenarios assume an increase in CDR, but "higher levels of CDR remains uncertain and associated with risks", Unep said.

By Georgia Gratton