Global warming accelerating, scientists warn

Activists gathered at the "dying" glacier on Pizol mountain in Switzerland to highlight the crisis. Photo: AP

A damning new UN report says the world is falling badly behind in efforts to slow climate change, with the five years to the end of 2019 set to be the hottest ever.



It comes ahead of a UN climate summit on Monday that will be attended by more than 60 world leaders, as Secretary-General Antonio Guterres pushes for countries to set bigger greenhouse gas reduction targets.



The World Meteorological Organisation, which compiled the report, said it "highlights the urgent need for the development of concrete actions that halt global warming and the worst effects of climate change".



The average global temperature from 2015 to 2019 is on track to be the hottest of any five-year period on record, according to the report.



The period "is currently estimated to be 1.1 degrees Celsius above pre-industrial (1850-1900) times and 0.2 degrees Celsius warmer than 2011-2015" it said. The report also warned that global sea levels rose at 5mm per year from 2015 to 2019, substantially faster than the average rate since 1993 of 3.2mm per year.



Guterres said last week the world was losing the race on climate change, with the latest report spelling out the extent to which the gap between what is required and what is happening is widening.



The amount of carbon dioxide going into the atmosphere between 2015 and 2019 grew by 20 percent compared with the previous five years.



"This reads like a credit card statement after a five-year long spending binge," said Professor Dave Reay, chair in Carbon Management at the University of Edinburgh.



"Our global carbon credit is maxed out," he added. "If emissions don't start falling there will be hell to pay."



The report says there is also no sign yet of reaching what is known as "peak emissions", the point at which levels will start to fall, though these are not growing at the same rate as the global economy.



The 2015 Paris Agreement saw countries lay out national targets to reduce their emissions in order to limit long term temperature rise by either 2 degrees Celsius or 1.5 degrees Celsius.



These are benchmarks that will limit in important ways the impact of warming on world weather systems.



But even if all countries meet the goals they set themselves, the world will warm by 2.9 degrees Celsius to 3.4 degrees Celsius, the report said.



The current levels of carbon reduction will need to be tripled to meet the 2 degrees Celsius goal and increased five-fold to meet the 1.5 degrees Celsius goal - but technically still possible. (AFP)