This year is almost certain to be the warmest that our planet has seen since at least 1880, according to new data released Thursday. Earth had its warmest October on record and warmest January through October period, according to the National Oceanic and Atmospheric Administration (NOAA).
This new data confirms previously released information from NASA and the Japan Meteorological Agency, but goes a step further by showing just how difficult it would be for 2014 to avoid setting an all-time temperature record.
In order for 2014 to come up short of the warmest year on record title, the months of November and December would each have to be colder than the 10th-warmest such months on record, according to Deke Arndt, chief of the climate monitoring division at the National Climatic Data Center (NCDC) in Asheville, North Carolina.
This is extremely unlikely to occur, considering that each of the last seven months (April through October) have been third-warmest or warmer. In addition, six of the last 12 months have tied or exceeded their warmest level on record.
"With two months left to go in the analysis it's becoming pretty clear that 2014 will end up the warmest year on record and the remaining question is by how much," Arndt told reporters on a conference call.
Even though the lower-48 states have had an extremely cold November so far, the Northern Hemisphere overall has continued to be much warmer than average.
The January-to-October period surpassed the previous record warm years of 1998 and 2010 in NOAA's database, the agency said Thursday.
This is unique because both of those previous years featured El Niño events, which raise global ocean temperatures and give the planet's overall temperature a boost. So far this year, an El Niño event has failed to materialize in the Pacific Ocean, despite being forecast to do so, yet the past six months, including October, have set records for the highest global ocean temperatures on record.
Parts of every major ocean basin in the world were record warm for the month, with particularly unusual warmth seen in the Western Pacific and the Indian Ocean, according to Arndt.
October 2014 also tied with June 2014 for the third-highest ocean temperature departure on average for any month on record since 1880. The second-highest departure from average occurred in August, while the all-time highest departure from average took place last month.
"Clearly the oceans are driving the warmth that we've seen around the planet most of the year," Arndt said.
A record warm 2014 could mark an end in a temporary slowdown in the rate of warming, which scientists think has been caused by a mix of manmade and natural factors, which has lasted for about the past 15 years. One of those factors was cooling ocean waters in parts of the Pacific, which appears to be reversing in a big way.
In addition to being on track for the warmest single year since 1880, we just had our warmest 12-month period of any 12 straight months on record, Arndt said. This breaks the record from the warmest 12-month period, which was set last month.
Globally, the Southern Hemisphere was record warm for October, while the Northern Hemisphere was third-warmest on record with a record high sea surface temperature. Record warmth occurred across much of southern South America and much of southern and western Australia, NOAA said. Record warmth was also observed in parts of southern Europe, the West Coast of the U.S., where California is going to have its warmest year on record.
Even if California is record cold during November and December, it is still likely that California would have its warmest year on record, said Jake Crouch, an NCDC meteorologist. The January through October period in California had an average temperature that was 1.6 degrees Fahrenheit warmer than the previous record warm such period.
The U.S. has not been on track for a record warmest year, having had its coldest year-to-date since 2009, NOAA found. However, its average temperature is still running above average, with a stubborn pattern of a warm West and cold East.
While instrument data only goes back as far as 1880, other climate records, from tree rings to coral reef samples, have shown that it is likely that the Earth has not been this warm in at least 4,000 years, with global levels of greenhouse gases at the highest level in human history.
Last week, preliminary NASA data showed it was the warmest October since 1880, tied with 2005, while surface data from Japan's Meteorological Agency showed it was the warmest October, hands down.
Separately, the University of Alabama at Huntsville's satellite dataset pegged the monthly average temperature as the warmest in its records, which date back to 1979, in a tie with October 2012. The satellite data offers somewhat of an independent check on the surface information, since satellites measure the global average temperature differently than surface weather stations.
The actual rankings from the different centers, especially for an individual month, are not as important as the long-term trend in global average temperatures, which shows a warming planet, due largely to the buildup in manmade greenhouse gases.
After all, the world has not seen a month with an average temperature below the 20th century average since February 1985, when People magazine named Mel Gibson the "Sexiest Man Alive" and the late Apple cofounder Steve Jobs turned 29.