People, Environment

September Ends Global Hot Streak

September Ends Global Hot StreakSeptember Ends Global Hot Streak

September 2016 was the second warmest ninth month of the year on record, according to NOAA, snapping a string of 16 straight months the average temperature set a record high.

The month was 0.04 degrees Celsius cooler than last year's record warm September, according to the state of the climate report released on Tuesday by NOAA's National Centers for Environmental Information.

Overall, the average temperature across all of the planet's land and ocean surfaces was 0.89 degrees Celsius warmer than the 1981-2010 average.

Almost the entire globe saw above-average temperatures in September. The lone cooler-than-average locations were Western Australia and a few other pockets over ocean areas.

The 16 straight months was the longest such stretch of months in which a new record high temperature was set for each respective month. Before this September, April 2015 was the last time Earth did not have a record warm month.

Records in NOAA's database date back to 1880, or 137 years.

  Record Warmest Year Still Likely

With the first eight months of 2016 being record warm and September ranking as second warmest, it's highly likely that 2016 will end up being Earth's warmest year on record. The top two warmest years on record are 2015, followed by 2014.

Even if the average temperature for the final three months of 2016 matches the 21st century average, the year would still end up being the warmest on record, NOAA says.

That scenario is shown in the chart below, which includes the current seven warmest years on record compared to how 2016 is trending so far. The black circles show how the line would trend if the final three months of the year were right at the 21st century average.

If the average temperature for October-December trended like 1998, the warmest year prior to the 21st century in the graph below, the year would end up as the second warmest on record just behind 2015. That is illustrated by the black triangles.

  September One of the Hottest

NASA's Goddard Institute for Space Studies found September 2016 was the globe's warmest September in their dataset dating to 1880.

The temperature anomaly of 0.91 degrees Celsius above the 1951-80 average barely topped the previous warmest September in 2014 by 0.01 degrees Celsius.

Starting with October 2015, 12 of the last 13 months have now been record warm, according to NASA's data.

NASA's analysis shows that temperatures were the farthest above average in parts of eastern North America, the Arctic, northwest Europe, Central Asia, and northeast Africa.

Few locations in the world saw below-average temperatures in September, including Western Australia, portions of Antarctica and central South America.

Another analysis from the Japanese Meteorological Agency said September was the second warmest on record in their database. JMA's records date back to 1891.

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