NOAA: Past 12 months global temperatures were warmest on record
The combined average temperature over global land and ocean surfaces for September 2014 was the highest on record for September, at 0.72°C (1.30°F) above the 20th century average of 15.0°C (59.0°F).
The global land surface temperature was 0.89°C (1.60°F) above the 20th century average of 12.0°C (53.6°F), the sixth highest for September on record. For the ocean, the September global sea surface temperature was 0.66°C (1.19°F) above the 20th century average of 16.2°C (61.1°F), the highest on record for September and also the highest on record for any month.
...
The first nine months of 2014 (JanuarySeptember) tied with 1998 as the warmest such period on record, with a combined global land and ocean average surface temperature 0.68°C (1.22°F) above the 20th century average of 14.1°C (57.5°F). If 2014 maintains this temperature departure from average for the remainder of the year, it will be the warmest calendar year on record.
The past 12 monthsOctober 2013September 2014was the warmest 12-month period among all months since records began in 1880, at 0.69°C (1.24°F) above the 20th century average. This breaks the previous record of +0.68°C (+1.22°F) set for the periods September 1998August 1998, August 2009July 2010; and September 2013August 2014.
http://www.ncdc.noaa.gov/sotc/global/2014/9