January Arctic Sea Ice Volume is Lowest On Record by a Considerable Margin
7
February, 2017
Almost
continuous warm, moist air invasions of the Arctic during fall and
winter of 2016 and 2017 have resulted in the lowest sea ice refreeze
rates on record. As a result, the amount of ice covering sections of
the Northern Hemisphere ocean is now remarkably lower than during
past comparable periods. In other words, we’ve never seen a winter
in which Northern Hemisphere sea ice was so weak and reduced.
One
key measure, sea ice volume, has shown particular losses when
compared to past years. And even taking into account a long term
trend of ice losses for the northern polar region that has been
ongoing since the 20th Century, the 2016-2017 losses stand out like a
flashing red indicator light. A trend directly related to the
human-forced warming of our world through fossil fuel burning and
related greenhouse gas emissions.
(Significant
sea ice losses during the winter of 2016-2017 show up clearly in the
above PIOMAS graph. PIOMAS is a model measure of sea ice volume. And
as you can well see when looking at the red line at the left hand
side of the graph, the departure from past years is currently quite
large. Image source: PIOMAS.)
In
the above PIOMAS graph we find that January sea ice volume averaged
around 14,000 cubic kilometers. This reading is roughly comparable to
the early July average for the period of 1979 through 2016 — a time
when the Arctic saw continuous declines in sea ice. The present
reading is also about 1,500 cubic kilometers below the previous
record low for the month of January set in 2013. And anyone looking
at the above graph can well see that the departure is significantly
below the trend line (about 8,000 cubic kilometers below the falling
38 year average for this time of year).
It’s
worth reiterating that these are the lowest sea ice volumes ever seen
for this time of year in the Arctic. A new record that comes after
consistent new record lows occurring throughout the past 38 year
period.
Presently,
approximate 5 C above average temperatures are dominating the region
above the 66 North Latitude.
Over the coming days, a pair of warm air invasions of the North Pole
region near 90 N are expected to push temperatures to more than 30
degrees Celsius above average and to near the melting point on two
separate occasions. This pair of, not at all normal, events will
likely produce additional sea ice losses in a polar region that is
already seeing very unusual low sea ice concentrations, volumes and
extents.
(Warm
storm invasions of the northern polar region that inject high heat
content, ice-melting moisture and far above average temperatures into
the High Arctic have been a frequent occurrence over recent months.
By February 10, GFS models predict that another such storm will push
temperatures to more than 30 degrees Celsius above average for the
North Pole and surrounding regions. This will produce yet one more
powerful blow to sea ice attempting to rebuild in the region. Image
source:
After
these events roar through, the
Jet Stream is predicted to flatten somewhat —
allowing cooler air to re-establish over the Central Arctic as warmer
air invades the mid-latitudes. As a result, air temperature anomalies
in the 66 N and above region are expected to fall back to a range of
1 to 2 C above average in the 7 to 14 day timeframe. Such a return to
closer to normal conditions may allow for more short-term bounce-back
toward previous record low ranges in the volume measure. But a much
longer period of closer to average conditions would be required for a
full recovery.
Overall,
refreeze season tends to last until April. So some time does remain
for a bit of recovery. And we have seen extent measures trend closer
to past record lows over recent days. However, considering the
massive losses experienced during fall-winter of 2016-2017, two
months is unlikely enough time to produce a significant recovery even
if cooling to more reasonable above average temperatures were to
occur and remain in place for an extended period.
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