News•February 2, 2015

One More Log on the Fire for 2014 As Hottest Year

If you need further confirmation that 2014 was the hottest year on record, the World Meteorological Organization has you covered.

The United Nations agency announced Monday that they, like various national agencies and informed by those agencies’ data, have placed 2014 atop the temperature records. They had the year coming in at 1.03°F above the long-term average of 57.2°F. So, let’s review who has put last year in first place:

NOAA? Check.
NASA? Check.
Japan Meteorological Agency? Yup.
WMO? Check.
UK Met Office? Them too. (Though they have it tied with 2010.)

Each agency can end up with slightly different temperature differences from year to year, as they handle their data a little differently, which can result in slightly different rankings. But this year, there was broad agreement, which is reflected in the WMO’s ranking, since they take all but the JMA numbers into account.

In a statement, the WMO did emphasize that the ranking was a close call (as the Met Office numbers show). Essentially, 2014, 2010 and 2005 were all about the same amount warmer than the average from 1961-1990, with 2014 just slightly edging out the other two years.

But far from muddying the waters, this potential three-way tie of years all in the 21st century emphasizes the long-term warming trend ultimately driven by the buildup of heat-trapping greenhouse gases in the Earth’s atmosphere. In fact, 14 of the 15 hottest years on record have come this century, the WMO noted. (The one outlier is 1998, a blockbuster El Nino year, which tends to elevate global temperatures.)

“The overall warming trend is more important than the ranking of an individual year,” WMO Secretary-General Michel Jarraud said in a statement. “Analysis of the datasets indicates that 2014 was nominally the warmest on record, although there is very little difference between the three hottest years.”

The WMO made their announcement in advance of another round of international climate negotiations taking place in Geneva next week. Those talks are aimed at hammering out an agreement on taking global action to slow the rate of greenhouse gas emissions.

In a separate analysis, Climate Central found that the odds of having 13 of the 15 hottest years on record (according to NOAA data) occur in the past 15 years without the push provided by global warming was about 1-in-27 million.

Another sign of the long-term warming trend is the lack of any record cold years since 1911. Since then, 19 records for hottest year, including 2014, have been set, according to another Climate Central analysis.

Even more amazing when considering the record warmth of 2014 is the fact that there was not a full-blown El Nino in effect, meaning that unlike in 1998, that wasn’t providing a major injection of heat.

Large swaths of the planet’s oceans were record warm last year, just not the ones typically associated with an El Nino. The oceans are where the vast majority of the excess heat trapped by carbon dioxide and other greenhouse gases is eventually stored. Some scientists think the astounding ocean warmth last year could be a sign that the seas are ready to belch back out some of that heat, re-intensifying the warming trend and putting an end to the so-called hiatus in the rate of surface warming.

Those oceans are still warm a month into 2015, but where the global temperature will fall for the year, we’ll have to wait and see.