Average global temperature between 2015-2019 is on track to be the hottest of any five-year period on record, a United Nations report by the world's leading climate agencies said on Sunday.

“It is currently estimated to be 1.1 degrees Celsius above pre-industrial (1850-1900) times and 0.2 degrees Celsius warmer than 2011-2015,” said the report titled United in Science, a synthesis of key findings.

Other major takeaways from the report include that the extent of Arctic summer sea ice has declined at a rate of 12 per cent per decade over the past 40 years, with the four lowest values between 2015 and 2019.

Overall, the amount of ice lost from the Antarctic ice sheet increased by a factor of six each year between 1979 and 2017, while glacier loss for 2015-19 is also the highest for any five-year period on record.

The report comes ahead of a major UN climate summit on Monday that Secretary-General Antonio Guterres has called to ask countries to raise their greenhouse gas reduction targets.

On this metric, too, the world is failing. The report found that rather than falling, carbon dioxide grew two per cent in 2018, reaching a record high of 37 billion tonnes.

More importantly, 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.