PARIS • The latest pledges from countries on how they plan to rein in fossil-fuel emissions mean that the world is closing in on its goal of keeping temperature increases to 2 deg C, a group of researchers has said.
If all nations fully implement the actions they have pledged, average temperatures will rise by 2.7 deg C by 2100 from pre-industrial times, according to the group, Climate Action Tracker (CAT), a joint project by four European institutions.
That is lower than the 3.1 deg C that they forecast last December and the first time that their prediction has dipped below 3 deg C.
The research underlines how much progress governments have made in their promises to fight climate change.
Envoys from more than 190 countries gathered by the United Nations aim to seal an agreement in Paris in December to limit fossil-fuel emissions everywhere for the first time.
If temperatures exceed the 2 deg C target, scientists say, the effects of climate change will become more intense, melting glaciers, pushing up sea levels and delivering longer droughts and more violent storms.
The UN's pledging process "has clearly led to progress but it is clear that, in Paris, governments must consider formally acknowledging that their first round of climate plans for 2025 and 2030 will not hold warming below 2 deg C", said Mr Bill Hare, a researcher at Climate Analytics, one of the project contributors.
Low-lying island nations and countries in Asia and Africa that are vulnerable to the impact of climate change want an even more stringent goal of 1.5 deg C. The world has already logged about 0.8 deg C of warming.
The uncertainty in analysing the effects of emissions reductions on rising temperatures is shown by the range of estimates for future warming.
Earlier in the week, researchers at Climate Interactive predicted warming of 3.5 deg C by 2100, given current pledges, while the International Energy Agency said in June that temperatures were likely to rise by 2.6 deg C by 2100, and by 3.5 deg C a century later.
Just over 140 countries out of 195 negotiating the global agreement, which will enter into force in 2020, had filed their contributions by Thursday - setting either five-year or 10-year emissions targets for themselves.
Representing nearly 80 per cent of global emissions, the pledges included the top three polluters: China, the United States and the 28-member European Union.
The CAT prediction also included estimated numbers for fourth-placed India, which announced its targets after the release of the review.
Climate envoy Laurence Tubiana of France, which will host the UN meeting to be held from Nov 30 to Dec 11, said the pledges to date marked a "very important step - we are nearing the scenario we had hoped for".
Looking forward, she added, "the essential part is that we put in place rules so that countries can ramp up their contributions regularly" after the Paris conference, she said.
To get on the path to 2 deg C, annual greenhouse gas emissions would have to be 11 billion to 13 billion tonnes lower in 2025 than those pledged, and 15 billion to 17 billion tonnes lower in 2030, the CAT found.
The United Nations' Intergovernmental Panel on Climate Change (IPCC) recommends slashing emissions by 40 per cent to 70 per cent by 2050 from 2010 levels and to near zero or below by 2100 for any chance at 2 deg C.
It was "not very likely" that submissions by countries which have not yet filed their pledges would get the world closer to 2 deg C before Paris, said Mr Hare.
"Falling below 3 deg C is symbolically important but insufficient," added climatologist Jean Jouzel, the IPCC vice-president. "The further we are from 2 deg C, the more difficult it will be to adapt (to climate change-induced challenges), especially for developing countries."
BLOOMBERG, AGENCE FRANCE-PRESSE