About that 'pause' in global warming …

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. According to a preliminary assessment by the Japan Meteorological Agency (JMA), 2014 was the hottest year on record for the globe. That surpasses the year 1998 (now in second place in the JMA data set) and 2013 and 2010 (now tied for third).

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 U.K. Met Office's Hadley Center — concur with the agency, it could be a serious blow to the "pause" argument.

Let's 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.

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 superhot El Niño year, and thus a fairly dramatic anomaly for the 1990s.

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 data sets 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?