The data are the first of the New Year to confirm many projections that 2016 will exceed 2015 as the warmest since reliable records began in the 19th century, it said in a report.
The Arctic was the region showing the sharpest rise in temperatures, while many other areas of the globe, including parts of Africa and Asia, also suffered unusual heat, it said.
A few parts of South America and Antarctica were cooler than normal.
