A July, 2015 study blended land and sea Surface temperature percentiles and NOAA has learned that it was the hottest on record.
The July average temperature across global land and ocean surfaces was 1.46°F (0.81°C) above the 20th century average. As July is climatologically the warmest month for the year, this was also the all-time highest monthly temperature in the 1880–2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C).
Separately, the July globally-averaged land surface temperature was 1.73°F (0.96°C) above the 20th century average. This was the sixth highest for July in the 1880–2015 record.
The July globally-averaged sea surface temperature was 1.35°F (0.75°C) above the 20th century average. This was the highest temperature for any month in the 1880–2015 record, surpassing the previous record set in July 2014 by 0.13°F (0.07°C). The global value was driven by record warmth across large expanses of the Pacific and Indian Oceans.
The average Arctic sea ice extent for July was 350,000 square miles (9.5 percent) below the 1981–2010 average. This was the eighth smallest July extent since records began in 1979 and largest since 2009, according to analysis by the National Snow and Ice Data Center using data from NOAA and NASA.
Antarctic sea ice during July was 240,000 square miles (3.8 percent) above the 1981–2010 average. This was the fourth largest July Antarctic sea ice extent on record and 140,000 square miles smaller than the record-large July extent of 2014.