Earth just went through its third-warmest January on record
Thursday, February 16, 2017, 2:03 PM - January is now the third warmest month of January on record, in 137 years, according to both NOAA and NASA, and this tally was punctuated by extreme warmth over parts of the northern hemisphere, and record lows for sea ice at both ends of the Earth.
NOAA and NASA records agree - January 2017 was the third-warmest month of January on record:
• NOAA: +0.88oC above the 20th century average
• NASA: +0.95oC above the 20th century average
These records are slightly different due to different coverage of their temperature records and different methods of computing averages. According to both agencies, though, in 137 years of record-keeping, only January 2007 and January 2016 were warmer.
Credit: NASA GISS
Extreme Northern Hemisphere heat
Although the month of January didn't tally up to be the hottest on record for the entire globe, there were some widespread hot-spots in certain parts of the globe.
Credit: NASA GISS
Of particular note are the intense blobs of heat over northern and eastern North America, and over Siberia. The pattern over Canada was felt particularly keenly, with the repeated snowfall events in the west and the January thaw in the east.
According to NOAA and the Rutgers Global Snow Lab, January saw the sixth largest Northern Hemisphere snow coverage in the over 50 years this has been tracked. While not an extreme or record-breaking amount, being 2.3 million square kilometres above the 1981-2010 average for the month quite likely had a connection to the excessive heat.
Even the hottest regions on the map were only around 4 or more degrees Celsius warmer than normal, on average. So, this was not going to break winter, where temperatures can get down into the minus 20s and minus 30s, at least. Warmer air does hold more water vapour, though, so being 4-5oC warmer than normal raises the moisture content of the air, providing more water to be frozen into snowflakes.
SPRING IS AHEAD: How will a developing El Niño impact our spring weather? The Spring Forecast premieres Monday, February 27 at 9 p.m. ET
Sea ice at record lows, across the globe
Whereas snow coverage was up in January, sea ice was down to record lows.
This wasn't just the Arctic, which has been suffering for years now, sea ice extents at both poles were at record lows for the month.
Based on National Snow and Ice Data Center records, Arctic sea ice was 1.26 million square kilometres below the 1981-2010 average for January. Antarctic sea ice, which had been generally trending higher up until last year, was 1.12 million kilometres below the 1981-2010 average.
While Arctic sea ice is approaching its winter maximum (and could we be seeing a new record low for that?), Antarctic sea ice is coming up on the summer minimum. The way things are shaping up in the Southern Ocean, it's looking like this will be the lowest Antarctic sea ice minimum ever recorded.
These findings for January are perfectly in line with what scientists have been expecting, going into 2017.
The latter half of 2016, from September through December, saw cooling temperatures across the globe, as we exited one of the strongest El Niño patterns on record and slipped into a fairly weak La Niña pattern in the Fall. By December, global monthly average temperatures were down around 3rd-warmest and thus January has continued that trend.
This continued trend of "non-record-setting temperatures" from late 2016 into 2017, is not, however, a signal that global warming, and the climate change that results from it, has slowed down or stopped. Carbon dioxide continues to build in the atmosphere due to human activities, and the extra heat from that added forcing continues to accumulate as well. The temperature fluctuations of these normal phenomena - El Niño and La Niña - are simply riding atop this extra heat, currently elevated by roughly 1oC, which makes the hot fluctuations more extreme, and the cold fluctuations less extreme.
What we are seeing since El Niño 2015/2016 dissipated is very similar to what we saw in 1999, after the record-setting 1997/1998 "super" El Niño. Then, it was the beginning of a temperature plateau that would last for several years - until 2005 for global temperatures to once again break records, and until 2015 before we saw the next extreme El Niño - but that temperature plateau was warmer than any of the other, previous ones that we have seen in the past four or five decades (at least). We are likely, now, seeing the start of a new, even hotter, temperature plateau, but how long this one will last, and what extremes will finally break it, are unknown.
As of now, as we progress through the latter half of Winter and into Spring, it's actually looking as though we may flip right back into an El Niño in the Pacific. If this does develop, it's doubtful we'd see a very strong pattern, so it (probably) won't rival the 2015/2016 event (although it is a bit too early to tell).
For the rest of 2017, even from our vantage point this early in the year, we can still tell that we're unlikely to see another record-breaking year. 2016 will retain its title as "hottest year on record" at least for a short while, and 2017 is expected to come in as - at least - one of the top five hottest in the books.
Come back for more updates on this as the year progresses.