2014
To Be Hottest Year on Record? Arctic Ocean, West Antarctic Heat
Spikes Amidst Scorching End to September
30
September, 2014
Strange
and anomalous heating of the Earth’s surface waters. That’s what
could best characterize the year of 2014. Waters warm enough to break
world records and all arrayed in extraordinarily odd distributions.
***
The
Summer of 2014 (June through August) was the hottest in the 135 year
global temperature record and likely the hottest in at least 100,000
years. According to the National Climate Data Center, global
temperatures were 0.88 degrees Celsius above the 1880 average and
0.71 degrees Celsius above average temperatures for the 20th Century.
Summer
of 2014 temperatures slightly edged out previous heat records set in
1998 by 0.01 degrees Celsius. But 1998 was a year during which a
raging El Nino was dumping immense volumes of Pacific Ocean heat into
the atmosphere. This year, summer conditions displayed Pacific Ocean
warmth in the Nino regions — but nowhere near enough heat anomaly
to shove the equatorial region into El Nino status. So a luke-warm
equatorial Pacific and possible pre El Nino in 2014 when combined
with a raging human heat forcing of the atmosphere is enough to beat
out the super El Nino of 1998 for record hottest summer, even if only
by a hair.
(Summer of 2014 beats out 1998 as hottest on record amidst steady and ongoing rise in global atmospheric temperatures. Image source: NOAA’s National Climate Data Center.)
The
hottest summer on record follows the hottest May on record and could
well include the hottest September on record. This is a strong trend
that may well be building 2014 into the hottest year on record. And
all without a pronounced El Nino so far.
For
if the final four months of this year all fall within the range of
first to fifth hottest, 2014 will be a record breaker.
A
Very Hot End to a Hot September
Preliminary
GFS measures show that September of 2014 may well be in
record-challenging range with global temperatures averaging between
+0.4 C to +0.7 C above the already hotter than normal 1979 to 2000
period. It was a period that featured ramping polar heat
amplification in both the Arctic and Antarctic. A period that
followed summer of 2014 trends showing extreme high temperature
departures in the Northern Pacific and even higher sea surface
temperature departures in the Arctic Ocean regions near the Bering
Strait.
The
last day of September closed near the top of this hot temperature
range with the global atmospheric anomaly at +0.69 C above the 1979
to 2000 average (which is about 0.3 to 0.4 C above the 20th Century
average respectively).
(September 30 global temperature anomaly map. Image source: University of Maine.)
Analyzing
the map above, we note strong polar amplification already advancing
in the Arctic region with a +1.15 C positive anomaly. We would well
expect this trend to continue through fall and winter due to a
combination of factors including — the amplified impact of
overburden greenhouse gasses during periods of seasonal darkness, a
very strong observed heating of the sea surface in Arctic regions
providing latent heat through the colder months, and pronounced
atmospheric heat transport through ridiculously resilient ridging
patterns over the northeastern Pacific and Scandinavia.
In
the Southern Hemisphere, we’ve also observed an extraordinary polar
heat spike ongoing over the region of West Antarctica in association
with an anomalous atmospheric ridge feature in that region as well.
West Antarctic temperature departures hit well above +20 C over
recent days. This excessive warm anomaly was enough to drive the
entire Antarctic zone to an extreme +3.09 C above that polar region’s
average for this time of year. Though it is still early spring for
the Antarctic, persistence of the West Antarctic ridge could have
serious impacts come summer time. So the feature will bear watching.
(Extreme positive temperature anomaly over West and Central Antarctica on September 30, 2014. Note the broad area of +20 C positive departure. Image source: University of Maine.)
Troubling
Arctic Ocean Heat Spike
But
perhaps the most troubling feature for September and, indeed, all of
the summer of 2014 is a massive accumulation of far warmer than
average surface ocean water in both the Northern Pacific and in the
Arctic Ocean.
The
Northern Pacific heat has occurred in conjunction with an anomalous
21 month long blocking pattern that has tended to fix in place a
south to north flow pattern and far warmer than average land and
ocean temperatures for the region. Sea surface temperatures in the
range of 2-3 C above average for a swath from California to Alaska
have remained in place for nearly two years running.
This
feature and now prevailing associated south to north wind pattern
appears to be driving warmer than normal waters through the Bering
Strait and into the already vulnerable Arctic zone. There, the added
warm water appears to have combined with the warming of a deeper, but
sometimes surface influencing, warm water flow newly emerging from
the Atlantic. These combined warm water flows have resulted in a
broad swath of 4 C + above 1979 to 2000 average surface water
temperatures ranging from the Bering Sea into the Chukchi, Beaufort,
East Siberian, Laptev and Kara Seas of the Arctic Ocean.
(Extreme global sea surface temperature anomaly of September 30, 2014 features extraordinary +4 C positive temperature departures in the Northern Polar Ocean. Image source: University of Maine.)
During
recent years featuring very low Arctic sea ice measures, August,
September and October have displayed very strong positive sea surface
temperature anomalies in the Arctic. These extraordinary sea surface
temperature values have tended to push global temperature averages
higher with a number of global heat records set despite the presence
of La Nina or ENSO neutral conditions in the Pacific. A clear
instance where human-driven polar heat amplification and heating of
the northern polar ocean is beginning to have a measurable and
substantial impact on global temperature variation as well as overall
rate of warming.
In
general, we find much of the global ocean heat spike clustered near
the northern polar zone. This is clearly visible in the anomaly color
display on the map above together with the +0.27 C of added heat in
the Northern Hemisphere surface ocean vs the Southern Hemisphere
Ocean measure.
A
final feature of this enhanced Arctic warming — increased instances
of microbial blooms in northern ocean surface waters — was plainly
visible in the MODIS shot during late September as well. In this case
a massive bloom covering a 550 by 100 mile swath of the Bering Sea
just south of the Bering Strait:
(Massive Bering Sea microbial bloom as visible in the LANCE-MODIS satellite shot on September 28 of 2014. For reference, the Bering Strait is to the right of frame. Bottom edge of frame is about 500 miles. Image source: LANCE-MODIS.)
In
these instances, concurrent with human-caused warming, large regions
of newly ice free water contain higher nutrient content than more
southerly waters. As the human heat forcing spurs these waters to
above average temperatures, ocean microbial activity becomes more
prolific — since larger numbers of microbes thrive in warmer
conditions. The result has been the appearance of very large blooms
in far northern waters during recent years.
Within
Striking Distance of a Record Hot Year — Serious Implications For
Weather and Climate
Despite
a Pacific El Nino that appears to be set on slow to low burn, if the
event appears at all, it appears possible that 2014 may be setting up
for a record breaking year. The factors driving this event include a
continued if very mild Pacific Equatorial warming together with far
more troubling heat amplification driven by human greenhouse gas
warming at the poles. The most troubling of these regions continues
to be the Arctic. And the added heat there will almost certainly
increase stress on vulnerable carbon stores as well as potentially
add to the human-spurred havoc now playing out in northern hemisphere
and global weather systems.
The
disposition of early fall atmospheric heating with high ocean heat
content near the northern polar zone certainly leaves wide the door
to future polar vortex disruption come winter 2014-2015 together with
providing a Jet Stream weakness that continues to facilitate
Northeastern Pacific Ocean ridge development. And, in the case of the
Northeastern Pacific especially, there are few challenges to that
very disruptive and damaging pattern on the near term horizon (30
day).
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