A map of the world showing the difference between September 2014 temperatures and the 1951-1980 averages. The darker the color, the greater the difference between last month's temperatures and the long-term average.

(NASA/GISS)

Last month was the warmest September in historical temperature records that date back more than 130 years, NASA said Sunday in its monthly global temperature report.

The global average temperature for September 2014 was 0.77°C (1.38°F) above the 1951-1980 historical average for the month, the agency reported Oct. 12 in its monthly Global Land-Ocean Temperature Index, which shows the temperature anomalies for each month of the year going back to 1880.

September 2014 marks the second consecutive record-breaking warmest month, as August 2014 also was the warmest such month in NASA's records. May 2014 also was the hottest on record, NOAA said earlier this summer, while four of the five hottest Mays have occurred in the past five years.

Though temperatures for the rest of the year remain to be seen, this year's record-breaking warmth indicates that 2014 could go down as the world's hottest year on record, according to temperature trends identified by NOAA's National Climatic Data Center.

See the complete Global Land-Ocean Temperature index at NASA.

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