One Month Above 1.5 C — NASA Data Shows February Crossed Critical Threshold

We had a number of preliminary indicators that February of 2016 was going to be ridiculously hot. And, according to new reports from NASA, those indicators appear to have born out.

In short, we’ve just experienced a month that was more than 1.5 C hotter than 1880s averages. It’s not a yearly average in this dangerous range — but likely the peak reading from a very intense El Nino combining with the growing base forcing of human climate change. That said, it’s a foretaste of what could very easily happen on a 5-15 year timescale in the annual measure if fossil fuel burning and related carbon emissions do not radically ramp downward.

February of 2015 was About 1.57 C Hotter Than 1880s Averages

According to NASA GISS, February of 2016 was the hottest February ever recorded by a long shot with global temperature departures hitting a never-before-seen above average range. Land and ocean temperature averages hit 1.35 C above NASA’s 20th Century baseline (1951-1980). This extraordinarily hot global reading represents a 1.57 C departure from average temperatures in the 1880s. In other words, for one month during February of 2016, global temperatures exceeded the dangerous 1.5 C threshold.

NASA record Warm February

(February of 2016 showed an extreme departure from global average temperatures. Much of the extra heat focused on the Northern Polar region with the High Arctic bearing the brunt of it. Image source: NASA GISS.)

Japan’s Met Agency also showed February temperatures exceeding 1.5 C above 1880s averages. So we only await NOAA’s findings for final confirmation.

Overall, these temperatures were the highest anomaly departure ever recorded in the NASA GISS monitor. The previous highest anomaly reading being January of 2016 at +1.14 C above 20th Century and +1.36 C above 1880s averages. Overall, the three month period of December, January and February hit an amazing +1.20 C above 20th Century averages or +1.42 C above 1880s averages. Overall, this three month departure is +0.51 C above peak three month departures during the 1997-1998 El Nino or a peak-to-peak warming from strong El Nino to strong El Nino at a rate of 0.28 C per decade.

Such high peak to peak increases may imply an acceleration above the baseline rate of warming of 0.15 to 0.2 C per decade since the late 1970s. However, such above baseline rates of warming will need to also bear out in the post strong El Nino record before such a claim can be made with any confidence.

Ridiculous Amount of Heat Over the Northern Polar Region

Looking at the geographical distribution of these extreme, above average, temperatures we find a broad swath of record heat in the range of 4 to 11.5 degrees Celsius hotter than normal covering a huge swath surrounding and including the Arctic. A region stretching from just north and west of the Great Lakes including Northwest Canada, Alaska, the Beaufort and East Siberian Seas, the Chukchi, the Laptev, the Kara, a huge expanse of Europe and Asia stretching from Eastern Europe to Lake Baikal and north to the Arctic Ocean, the Barents, the Greenland Sea, the Northeast tip of Greenland and most of the region of the High Arctic above the 80 degree North Latitude line, all experienced these extremely warm readings.

Still very warm 2 to 4 C above average temperatures surrounded much of this zone even as a broad 2-4 C above average hot spot is apparent over the record El Nino region of the Eastern Equatorial Pacific. Smaller regions experiencing similar 2 to 4 C anomalies include sections of Brazil and Columbia, a region over Southern Africa, Northern Australia and Northern New Zealand.

Overall, very few regions show cooler than normal temperatures — though the cool pool just south and east of Greenland continues to stand out as a feature that is likely related to human-forced climate change.

Feb zonal anomalies NASA

(Zonal anomalies show an extreme polar amplification signature for February of 2016. Image source: NASA GISS.)

The disposition of extreme temperature departures centering over the Northern Polar zone is indicative of a pattern of extreme polar amplification during a strong El Nino year. As such, we can infer that the circumpolar winds did little to keep warm, Equatorial Pacific air isolated to the lower Latitudes and instead had weakened to the point that Equator to Pole heat transfer was facilitated.

The temperature anomaly map at the top implies a warm meridional air flow issuing directly from the Equatorial Pacific and over the Northeast Pacific and Western North America. A second implied meridional wind pattern appears running from the Eastern Equatorial Atlantic over Western Europe and the Barents and Greenland seas. These dual Equator to Pole warm air slots appear to have helped to push High Latitude zonal anomalies in the polar region to very extreme warm temperatures for February with the highest departures approaching 6 degrees Celsius above average for the entire region north of the 80 degree Latitude line.

Arctic Degree Days above Freezing

(We’re going to need a bigger graph to measure the Freezing Degree Day anomaly below average which has now hit near -1,000. An above average warmth that has continued since a spate of record Winter heat during February. It’s an all-time low in a measure that typically doesn’t level off until June. For reference, the less Freezing Degree Days, the closer the Arctic is to thawing. Image source: CIRES1.)

Zonal anomalies remain high above the 45 degree North Line — hitting a steep slope from 2 C to 6 C as we progress northward. An Equatorial peak in the range of 1.3 C above average is also observed near and just south of the Equator. But despite an extreme El Nino, these departures are nowhere near those seen in the upper Latitudes of the Northern Hemisphere. Pretty much all zones except for the heat sink region in the 60s South Latitude over the Southern Ocean and the far south over Antarctica experienced above average temperatures for the month.

Conditions in Context — Signature of Climate Change in the Anomaly Maps Continues, Global Temperatures to Settle Back into a New High Range

The extreme polar warming, the visible warm air slots facilitating Equator to Pole heat transfer, and the overall very strong global temperature departure for February continue to express the signature of human forced climate change as predicted by many of the global model runs. The extreme Winter heat in the Arctic — while a sign of things to come during this strong El Nino year — is also an early blow to snow and ice in the Arctic for 2016 and 2017. Already, snow totals are at or near record low extent levels. Meanwhile, sea ice volume during February returned to near new record low levels as measured by PIOMAS. As a result, the melt risk to both sea and land ice in the Arctic will likely be quite high over the next two years.

GFS_anomaly_timeseries_global

(GFS temperature anomaly time series shows peak February 2016 global temperatures falling off implying a March global temperature average that will likely be somewhere between January and February values. Perhaps in the range of near 1.4 C above 1880s or 1.2 C above the NASA baseline. Image source: Karsten Hausten using GFS data.)

It is worth noting, though, that February of 2016 will likely be the highest monthly temperature anomaly we see for some time. A record El Nino is fading away from peak intensity and NOAA is now predicting a 50 percent chance of La Nina conditions by Fall. We can expect to see global temperatures now begin to fall off a bit as a record El Nino starts to fade. To this point, 2016 will likely hit a departure range near 1.2 or 1.3 C above 188os values. Post 2016 temperatures will likely hover up to 0.2 to 0.4 cooler than those values during La Nina years, with new global records possible at the onset of El Nino again in the 3-5 year timeframe.

To be very clear, though ENSO sets the short term trend, the long term trend is governed by a human forced accumulation of heat-trapping gasses. And as long as that continues, the heating we’ve experienced will also continue. Finally, since we are now very close to hitting dangerous 1.5 and 2.0 C warming thresholds (possible within 5 years for 1.5 C and 15 years for 2 C in the worst case), we should be very clear that we are just passing the most recent peak in a long progression. The trend, therefore, is up and we have now been thrust into more dangerous times.

Links:

NASA GISS

The Roof is On Fire

Japan’s Met Agency

NOAA El Nino

Karsten Hausten

CIRES1

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