Speaking on the Senate floor in July, Oklahoma's James Inhofe -- soon to head, once again, the Senate's Environment and Public Works Committee -- made a claim that has become quite prevalent among skeptics of climate change.
"For the past 15 years," Inhofe said, "temperatures across the globe have not increased."
Inhofe was offering one of the favorite arguments of skeptics, namely, that global warming paused or slowed down since the very hot year of 1998.
But the argument has one big problem. This:
What you're looking at is a preliminary assessment by the Japan Meteorological Agency (JMA) of how 2014's globally averaged surface temperatures compare with those of prior years, all the way back to 1891. Based on this data, 2014 was the hottest year on record for the globe. That surpasses the year 1998 (now in 2nd place in the JMA dataset) and 2013 and 2010 (now tied for 3rd).
You'll also note, incidentally, that while the dataset is noisy, the upward trend is quite clear, and the decade of the 2000s is plainly warmer than the decade of the 1990s. So much for any "pause" in global warming.
Japan's is the first major meteorological outlet to pronounce on how 2014 ranks for temperatures. But if others -- the National Oceanic and Atmospheric Administration, NASA, and the UK Met Office's Hadley Center -- concur with the agency, it could be a serious blow to the "pause" argument.
Let's first consider the "pause" notion itself. It went truly mainstream in 2013, when the U.N.'s Intergovernmental Panel on Climate Change released the first part of its much awaited Fifth Assessment Report.
In a poorly worded statement, a leaked draft of the IPCC's report observed that the rate of global temperature increase, during the 15 year period from 1998 to 2012, was somewhat less than the rate of increase from 1951 to 2012. In other words, while the IPCC didn't say the globe had stopped warming, it did suggest a situation that is a bit like a driver easing off the accelerator in a moving car.
This led to voluminous media coverage of the so-called "pause" and how much it allegedly undermined arguments about global warming -- an analysis by Media Matters of coverage of the IPCC report release found that 41 percent of stories cited the "pause."
But as it turned out, this was all much ado about nothing. The IPCC would later emphasize, in its finished report, that "trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends." Moreover, many scientists observed that using 1998 as a beginning date in the first place is misleading, because 1998 was a super hot El Niño year, and thus a fairly dramatic anomaly for the 1990s (as you can see in the chart above).
The weakness of the "pause" argument is perfectly captured in this GIF from the website Skeptical Science, showing that you can still have global warming even if you have shorter periods during which temperatures don't rise much:
In the end, then, the "pause" argument largely relies on the then-record temperatures of 1998 in order to create the impression that there's been little or no global warming ever since.
Yet the fact remains that the 2000s were considerably hotter than the 1990s, and indeed, in most datasets 1998 isn't even the hottest year any longer. Without even taking 2014 into consideration at all, NASA considers 1998 merely the fourth hottest year (behind 2010, 2005, and 2007, and tied with 2002) and NOAA considers it third (behind 2010 and 2005).
So what happens to the "pause" if 2014 now becomes the hottest year?
At least for some expert agencies, 2014 is looking more and more like it will surpass 1998 and all other contenders. And this is particularly remarkable because unlike 1998, 2014 is not an official El Niño year (these years tend to be hotter).
We've already seen the Japan Meteorological Agency's preliminary analysis. NOAA and NASA are slated to jointly release their assessments of 2014's temperatures on January 16. The Hadley Center, meanwhile, just affirmed that 2014 was the hottest year on record for the UK in particular -- and it is also expected to weigh in on temperatures globally soon enough.
So what can we expect from these agencies?
As far as NOAA goes, a 2014 record seems pretty likely. "NOAA’s in the bag," says John Abraham, a climate scientist at the University of St. Thomas in Minnesota who tracks global temperatures carefully, and has himself already declared 2014 a new record temperature year.
Indeed, while NOAA has only released global averaged temperature analyses through November so far, its last release included this helpful figure, showing where 2014 currently stands in the record books, and what would have to happen in order for it to set a new record (or fail to). Basically, it looks pretty hard for 2014 to fall short, assuming last month's temperatures were reasonably warm:
As for NASA and the Hadley Center, it remains to be seen. When it comes to NASA, Abraham says he sees "probably a 60 to 70 percent chance they’ll break the record."
So at this point, it seems likely that for at least some of the official agencies, 2014 will go down in the record books.
So can 2014's temperatures finally silence global warming "pause" mongers, like Inhofe?
I asked several prominent climate scientists this question. "The record-breaking temperatures should put to rest once and for all the silly claim by contrarians that climate change has somehow stopped or stalled," observed climate researcher Michael Mann from Penn State. "In fact, the warming of the globe continues unabated as we continue to burn fossil fuels and increase concentrations of planet-warming greenhouse gases."
"2014 is now the warmest on record by only a tiny amount," added Kevin Trenberth, a much cited climate researcher at the National Center for Atmospheric Research. "Nevertheless it continues the human-induced upward trend in temperatures that has been evident since the 1970s. Starting trends in 1998 is quite misleading. Undoubtedly Mother Nature will continue to surprise us, but we should expect continued increases in extremes of temperature, heat and wild fires, and stronger storms and more intense droughts."
In fairness, in a technical sense 2014 is just another year and just another data point. Despite the January ritual of tallying up each year's temperatures and ranking it against prior years, what actually matters (as always) is the trend, not the individual year. But as we've seen, the global warming trend is intact -- 2014 may just be an exclamation point on top of it.
Indeed, this year -- 2015 – the temperatures of 2014 could take on major significance. After all, the world is now racing to complete a global climate agreement this December in Paris. A new temperature record for 2014 would surely light a fire under negotiators.
Meanwhile, there remains a 65 percent chance that we'll see an El Niño -- which could also help drive a new temperature record -- in 2015.