According to the World Meteorological Organization, 2015 looks like it’s going to be the warmest year recorded, ever since record keeping began in 1880. This is based on temperature readings from January to October. The period from 2011 to 2015 has been the warmest five-year period on record. The previous warmest year on record was 2014.
Image Credits:https://www.wmo.int/ for global temperature image
Sources: https://www.wmo.int, https://www.nasa.gov