A record global temperature, exceptionally low sea ice, and an unabated rise in sea level and ocean heat were all witnessed last year, according to a report from the World Meteorological Organization (WMO).
The State of the Global Climate in 2016 explains that a powerful El Niño event, combined with long-term climate change caused by greenhouse gas emissions, was responsible for the rise in warming last year.
In addition, the report reveals that carbon dioxide (CO2) levels in the atmosphere have reached new highs of 400 parts-per-million, which will not fall below that level for many generations to come.
WMO secretary-general, Petteri Taalas, said: "This report confirms that the year 2016 was the warmest on record - a remarkable 1.1°C above the pre-industrial period, which is 0.06°C above the previous record set in 2015.
"This increase in global temperature is consistent with other changes occurring in the climate system. Sea surface temperatures were also the warmest on record, global sea levels continued to rise, and Arctic sea ice extent was well below average for most of the year.
"With levels of CO2 in the atmosphere consistently breaking new records, the influence of human activities on the climate system has become more and more evident."
Some key findings in the WMO report are shown below:
Other studies, not included in the WMO report, indicate that extreme weather and climate conditions have continued into 2017, suggesting that ocean heat may have increased more than previously reported, and that there has been no easing in the rise in atmospheric CO2 concentrations.
In addition, scientific research shows the Arctic has witnessed the polar equivalent of a heatwave at least three times so far this winter, with temperatures in the ice-freezing period, close to melting point.
While in the US, 11,743 warm temperature records were broken or tied in February alone, according to the US National Ocean and Atmospheric Administration.
World Climate Research Programme director, David Carlson, said: "We are seeing remarkable changes across the planet that are challenging the limits of our understanding of the climate system. We are now in truly uncharted territory."
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