Last year was one of the three warmest on record, with glaciers melting, sea levels rising and a spate of wildfires, heatwaves and droughts, research published in the Bulletin of the American Meteorological Society (BAMS) showed.
The BAMS annual State of the Climate Report, by 528 climate scientists from 61 countries, said only 2015 and 2016 were hotter than 2019, based on records dating to the mid to late 1800s.
Each decade since 1980 has been successively warmer than the preceding one, with the most recent (2010-2019) being around 0.2 degrees Celsius warmer globally than the previous (2000-09).
For the 32nd consecutive year, 2019 saw the loss of mass from mountain glaciers, while lake temperatures were above the long-term average and permafrost temperatures continued to rise.
In 2019, global mean sea level set a new record for the eighth year running, reaching 87.6 millimeters (mm) above the 1993 average when satellite measurements began, with an annual average increase of 6.1 mm from 2018, the report said.
Greenhouse gas emissions, which contribute to climate change and pollution, increased. Carbon dioxide emissions rose by 2.5 parts per million (ppm), nitrous oxide by 1 part per billion (ppb) and methane by 9.2 ppb, the report said.
"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," said Robert Dunn from the U.K.'s Met Office, which contributed to the report.
"The rise in global temperature is linked to another climate indicator: the ongoing rise in emissions of greenhouse gases, notably carbon dioxide, nitrous oxide and methane."
The pressure is building for governments to do more to limit emissions to maximize the chances of capping a rise in average global temperatures at 1.5 C, a goal enshrined in the 2015 Paris climate agreement.
