2016 was the warmest year on record according to data released by the United States' National Oceanic and Atmospheric Administration. The data compares the average global temperature for each year, from 1880 to 2016, with the average global temperature for the whole of the 20th century (represented as 0 on the vertical axis in the visualisation below). For example: the January 2016 average temperature was just over 1 degree celcius warmer than the average January temperature for the whole of the 20th century.
Each line in the chart below represents a year and it's clear that the monthly average temperatures in the 2000s are higher than the global average for the 1900s.
Related: Global CO2 Emissions