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Gale After Gale After Gale Dumped Two and a Half Feet of Rain Upon Scotland and Wales This Winter
1
March, 2016
Reports
from the UK Met Office are in.
And we can say now with confidence that the UK have never seen
weather like what they experienced this Winter. It looks like a storm
track super-charged by climate change really socked it to the region
this year. That we’ve just passed a winter worse than the then
record years of 2013 and 2014 — only two years on.
A
Stormy New Climate State for the North Atlantic
For
the UK and for North Atlantic weather stability in general, the sea
surface temperature anomaly signature in the graphic below is bad
news. The cool pool just south of Greenland (indicated by the swatch
of pale blue) is a new climate feature. One
that appears to be related to glacial ice melt outflow from
Greenland.
(10
degree Celsius above average sea surface temperatures off North
America in today’s ensemble sea surface temperature model graphic
are just insanely warm. Ocean surface anomalies used to rarely exceed
2 degrees Celsius warmer than average. These spikes off North America
are an indication that the Gulf Stream is backing up and that
overturning circulation off Greenland is slowing down. Image
source: RTG-SST/NCEP
/US National Weather Service/Earth Nullschool.)
Such
melt outflow tends to slightly freshen sea surface waters. Freshening
waters keep more heat locked into the ocean’s depths. They tend to
cool the surface waters. And they slow down an ocean overturning
circulation that, in the North Atlantic, drives the flow of the Gulf
Stream.
A
slowing Gulf Stream delivers less heat to this zone even as it piles
more heat up off the North American Coast. As a result, a warm west,
cool east dipole tends to develop. In the cool region south of
Greenland, unusually strong storms have developed more and more
frequently — with a dramatic impact on UK weather. The storms feed
on this temperature differential even as they have gorged on heat and
moisture streaming northward in a meridional flow over Western
Europe. The results this year were nothing short of
record-shattering.
Hottest
and Wettest
For
England and Wales, with temperatures ranging about 2 degrees Celsius
above average for December, January and February, 2015-2016 probably
beat out 2007 and 1989 as the hottest Winter on record.
Meanwhile, Wales
and Scotland saw the most rainfall ever recorded —
with totals for both regions hitting around 756 millimeters or about
two and one half feet. That’s
even more rainfall than the previous record stormy Winter of 2013 and
2014.
(Yet
one more gale sets up to hammer Ireland, the UK and Scotland by
Thursday. Four months of ongoing stormy conditions appears set to
continue through to at least mid-March. Image source: NOAA’s
Ocean Prediction Center.)
These heavy
rains set off severe floods and
damaged homes, roads, and bridges throughout the UK with the worst
damage focusing in on regions to the North. One heavy precipitation
hot spot — Argyll — saw an extraordinary 1035 mm or 3.5 feet of
rainfall over the three month period. The Met Office is quick to
point out that though December, January and February were the wettest
on record since 1910, heavy
rainfall events began in November —
resulting in what amounts to a relentless four month pounding as
storm followed storm and flood followed flood.
And,
it appears, this persistent and ongoing storm pattern has not yet
changed. For the North Atlantic remains riled — setting up to hurl
a new gale-force low at Ireland and the UK this week. With the
weather pattern essentially stuck in stormy since November, folks
from these regions have got to be asking — when’s it going to
end? As storms continue to fire off in the dipole zone above, it
appears it will likely last until at least mid-March.
Links:
Hat
tip to Colorado Bob
Hat
tip to TodaysGuestIs
Hat
tip to Dan Combs
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