Last year was the hottest year on record, climate experts at the US National Oceanic and Atmospheric Administration (NOAA) say.

An analysis of surface temperature measurements by NOAA and NASA shows the 10 warmest years on record have occurred since 1998.

Earth's average surface temperature has warmed by about 0.8 degrees Celsius (1.4 degrees Fahrenheit) since 1880, according to NASA.

The trend is being fuelled by the increase in carbon dioxide and other human emissions into the planet's atmosphere, says the space agency.

Record temperatures were notched up in 2014 throughout the western US, South America, most of Europe, northern Africa and parts of Australia, NOAA said.

The climate agency said the average global temperature last year was 14.6 Celsius (58.24 Fahrenheit).

Earth's previous hottest years on record were 2010 and 2005, according to NOAA.

Last month was also the warmest December on record, said the climate agency.