The past decade was the hottest for the world in records dating back to the Industrial Revolution, a new report has warned.
Last year was one of the three hottest years since the records began in the 1800s, only outstripped by 2016, and 2015 in some analyses, the 30th edition of the Bulletin Of The American Meteorological Society said.
The data for last year showed the global climate was continuing to change rapidly, experts said, with consequences from melting glaciers to exceptional wildfires.
The peer-reviewed State Of The Climate report said 2019 saw out the warmest decade on record, and that each decade since 1980 had been successively warmer than the one before.
The last decade, 2010-2019, was 0.2C warmer than the previous 10 years from 2000-2009.
And the years since the turn of the millennium had been warmer than any other comparable period since the Industrial Revolution, climate experts warned.
All the years after 2013 had been warmer than any previous years dating back to the mid-1800s, the evidence showed.
The report, which has contributions from climate scientists from around the world, including from the UK Met Office, also said lake temperatures were above long-term averages, and temperatures for permafrost - or permanently frozen ground - were increasing.
The growing season in the northern hemisphere was eight days longer than average in 2019, mountain glaciers shrank across the globe for the 32nd consecutive year and wildfires raged in Australia, the Amazon, Indonesia and Siberia.
Robert Dunn from the Met Office said: "The view for 2019 is that climate indicators and observations show that the global climate is continuing to change rapidly.
"Global average temperature is perhaps the simplest climate indicator through which to view the changes taking place in our climate.
"2019 was one of the top three warmest years in the historical record dating back to 1850.
"It also marks the end of a decade in which the average global temperature had risen by 0.2C when compared with the previous decade.
"And this millennium has been warmer than any comparable period since the Industrial Revolution.
"A number of extreme events, such as wildfires, heatwaves and droughts, have at least part of their root linked to the rise in global temperature."
And he said the rise in global temperatures was linked to the ongoing increase in emissions of greenhouse gases such as carbon dioxide.