The World Meteorological Organization has confirmed that 2016 made history with a record global average temperature, exceptionally low sea ice, and ongoing increases in sea levels and ocean heat.
In its annual statement on the Global Climate, the WMO said that extreme weather and climate conditions have continued into 2017.
Having pooled together all temperature data sets available in different parts of the world for 2016, the WMO said last year was the warmest on record for both land and the oceans, and for both the northern and southern hemispheres.
The average temperature was 1.1C above pre-industrial levels, which it said is remarkable.
It pointed out the influence of human activities on our climate system has become more and more evident.
The level of carbon dioxide in the atmosphere reached the symbolic 400 parts per million and will not fall below that for many generations to come.
However, 90% of the extra energy trapped by greenhouse gases goes into heating the oceans and causes them to expand.
This, along with melting glaciers and ice caps, has now resulted in an average 20cm rise in sea levels since the start of the 20th century.
Last year the extent of global sea ice dropped more than 4 million square km below the historical average which was unprecedented.
The report warns that changes in the Arctic are leading to a shift in wider oceanic and atmospheric circulation patterns.
This is affecting weather in other parts of the world because of waves in the jet stream, the fast moving band of air that helps regulate regional temperatures.
WMO Director David Carlson said we are seeing other remarkable changes across the planet that are challenging the limits of our understanding of the climate system.
The report notes a litany of extreme weather events last year, including severe droughts that brought food insecurity to millions in southern and eastern Africa and Central America.
It also cites highly destructive wildfires such as that at Fort McMurray in Albert Canada which burned for two months, destroyed 590,000 hectares, 2,400 buildings and resulted in many billions of dollars worth of losses.
And the most damaging meteorological disaster of any type last year, Hurricane Matthew, which hit Haiti, killed at least 546 people, and left 1.4m people in need of humanitarian assistance.