The prediction, by Britain's Met Office, for the possibility of a trio of record-breaking years comes just days after almost 200 nations agreed in Paris to a new global agreement to tackle climate change.

Under the pact, to take effect from 2020, nations would review efforts to curb greenhouse gas emissions every five years with the aim of keeping temperature increases to "well below 2 degrees" of pre-industrial levels.

The Met Office's release on Thursday of its annual global temperature forecast comes as south-eastern Australia swelters in what is expected to be record early-season heat.

Adelaide is on course to mark four days in a row of 40-plus days by Saturday, the first time such a run has been recorded in December.

The Met Office said this year was on track to eclipse 2014 as the hottest year for average sea- and land-surface temperatures. 

Using data for the first 10 months of 2015, the temperature was 0.72 degrees above the 1961-90 average and well above 2014's record 0.61 degrees above the norm.

The Met Office predicts 2016 will spike even higher, with a central prediction for a temperature anomaly of 0.84 degrees above the 1961-90 average.

"This forecast suggests that, by the end of 2016, we will have seen three record, or near-record years in a row for global temperatures," Adam Scaife, head of long-range prediction at the Met Office, said.

Australian heat

Climatologists say the record heat is the result of the background climate change triggered by human activities, such as burning of fossil fuels, combining with natural cycles, particularly the monster El Nino in the Pacific.

During El Nino years, altered Pacific wind patterns lead to the ocean tending to absorb less heat from the atmosphere. Rainfall also tends to shift eastwards, leaving eastern Australia relatively dry.

With less moisture available during dry years for evaporative cooling, temperatures - and the associated bushfire risks - can soar in spring and summer across south-eastern Australia.

The Bureau of Meteorology is forecasting severe heatwave conditions over almost all of Victoria from Friday to Sunday, with pockets to Melbourne's east and south-east NSW likely to experience extreme conditions.

While blasts of summer heat are not uncommon, it is unprecedented to have such warmth in places such as Adelaide this side of January.

Still chart-topping

The forecast for a hot 2016 globally is remarkable, given that records continue to tumble for 2015.

New data out overnight from the US National Oceanic and Atmospheric Administration showed that last month was the hottest November for global sea- and land-surface temperatures - extending the run of seven consecutive record-breaking months.

The November average temperature was 0.97 degrees above the 20th-century average, beating the previous record for the month - set in 2013 by 0.15 degrees, NOAA said.

November's anomaly was the second largest for any month in the 136 years of NOAA records, shy only of October's record departure from the norm.

The northern autumn/southern spring was also the hottest on record, as were the first 11 months of 2015.

As shown in the following chart, 2015 is notably warmer than the previous six warmest years, all of which have come since 1998.