2017 is second-warmest year on record, NOAA says

This year -- 2017 -- is the second-warmest year on record for the entire globe, the National Oceanic and Atmospheric Administration said Wednesday. 

The records date back 138 years to 1880, the NOAA said. 

September was the fourth-warmest September on record and saw a number of weather anomalies across the globe. Those included Hurricane Irma, which churned from Aug. 30-Sept. 16 with winds that reached over 180 mph, and Hurricane Maria, which formed on Sept. 16 and did not dissipate until Oct. 3 and had maximum sustained winds of more than 170 mph. 

Hurricane Irma was the strongest hurricane since 2005's Hurricane Wilma, and Hurricane Maria was the strongest hurricane to hit Puerto Rico since 1928.

North America had the eighth highest September temperature on record, and record and near-record temperatures were recorded in the Midwest and the lower Mississippi Valley. 

In the Arctic, the sea ice extent — or the measurement of the area of the ocean with at least some sea ice — was 25.5 percent below the 1981-2010 average, and the seventh smallest for September since records began in 1979. The Antarctic sea extent was 4.2 percent below the 1981-2010 average, the second smallest sea ice extent on record, behind 1986.

Africa had the highest September temperature since continental records began in 1910. Much of Asia (excluding Russia) had warmer than average temperatures, with Bahrain having the warmest September since 1902. Much of Australia had above-average temperatures, and Australia set a record for the warmest day in September on the 22nd of the month. 

Meanwhile, much of Europe had cooler than average temperatures. Ireland and Austria had their coolest Septembers since 2009 and 2007, respectively. Russia also recorded cooler than average temperatures.