The amount of sea ice at the Earth's poles fell to a record low for January, while the planet's temperatures last month were the third highest in modern times.
The monthly report by the National Oceanic and Atmospheric Administration is the first of its kind released in 2017, and comes on the heels of the third year in a row for record-setting heat established in 2016.
The US federal agency's analysis of global sea surface and land temperatures found that January's temperature was 1.58 Fahrenheit (0.88 Celsius) above the 20th century average of 53.6 F (12 C).
"This was the third highest for January in the 1880–2017 record, behind 2016 (highest) and 2007 (second highest)," said the report.
Those unusually warm temperatures contributed to the melting of sea ice in the Arctic, where the average ice cover for January was 487,000 square miles (1.26 million square kilometers) -- or 8.6 percent below the 1981–2010 average.
"This was the smallest January extent since records began in 1979 and 100,000 square miles smaller than the previous record set in 2016," said the report.
In the Antarctic, sea ice extent for January was 432,000 square miles (22.8 percent) below the 1981–2010 average.
"This was the smallest January Antarctic sea ice extent since records began in 1979 and 110,000 square miles smaller than the previous record set in 2006," it added.
Despite the loss of sea ice, precipitation varied widely across the globe last month.
Snow has been falling more heavily than usual in the Northern Hemisphere, where snow cover extent during January reached 890,000 square miles above the 1981–2010 average.
"This was the sixth largest January Northern Hemisphere snow cover extent in the 51-year period of record," said the study.
"The North American snow cover extent was the 13th largest on record, while the Eurasian snow cover extent was the seventh largest."