October 2016 tied with 2003 as Earth's third warmest October since record keeping began in 1880, said NOAA's National Centers for Environmental Information (NCEI) on Thursday. October 2016 was 0.73°C (1.31°F) warmer than the 20th-century October average; the only warmer Octobers were during the two previous years, 2015 and 2014. NASA reported that October 2016 was the second warmest October in its database, behind October 2015. October 2016 was Earth’s coolest month (relative to average) since November 2014, which was 0.69°C (1.24°F) above average. This October was also the first month since April 2015 that failed to set a global heat record in either the NASA or NOAA database.
As we blogged about on November 11, a weak La Niña event is now underway in the Eastern Pacific. The cool waters present in that region have helped cool the planet slightly below the record warm levels observed during the strong El Niño event of 2015 - 2016. The fact that October 2016 was still the 2nd to 3rd warmest October on record despite the presence of La Niña can mostly be attributed to the steady build-up of heat-trapping greenhouse gases due to human activities. NOAA’s global surface temperature for the year so far (January-October 2016) is an impressive 0.97°C (1.75°F) above the 20th-century average and 0.10°C (0.18°F) warmer than the previous January-to-October record, set in 2015. Remarkably, no land areas were cooler than average for the year-to-date. Barring an asteroid impact or the largest volcanic eruption in human history sometime in the next month, it is almost certain that 2016 will end up as the warmest year on record for the planet, giving us three consecutive warmest years on record.