North
Atlantic Ramping up to ‘Storms of My Grandchildren’ to set off
Major Flood Event for Tempest-Tossed England?
30
January, 2014
Under
the ongoing insults of human-caused climate change, the North
Atlantic is ground zero for the potential development of the worst
storms humankind has ever experienced. And indications are that the
ramping up to this dangerous time may well be starting now.
The
temperature related weather instabilities between the warming North
Atlantic, the melting but still frigid ice packs of Greenland, the
retreating polar sea ice, a continental North America enduring a
series of polar vortex collapse events flushing cold air south as the
Arctic experiences its warmest readings in an age, and an interior
Europe and Asia that are also experiencing mass migrations of cold
air fleeing the ever-warmer Arctic are just screaming.
A
bite of warm air and related warm ocean water has flooded a large
region between Scandinavia, Svalbard and Novaya Zemlya, making its
home where winter sea ice once resided. The waters near Greenland are
now melt-cooled by the 500 gigatons of average annual glacial outflow
occurring there. And the never-ending influx and concentration of
heat in the Arctic has set the Jet Stream into a fit of wild loops
and whirls.
All
these changes result in a high degree of weather instability, in a
setting off of extreme weather events, of great switches from cool,
to extreme hot, from record drought to record deluge. In the past few
years we’ve seen these kinds of extreme weather events occur with
increasing frequency. But now, a new kind of extreme event is
beginning to emerge, a kind of event that may well be prelude to ‘The
Storms of My Grandchildren’ Dr
James Hansen alluded to in his prescient book examining the ultimate
consequences of an ongoing and devastating human greenhouse gas
emission.
The
Breeder of Storms: Our Warming-Ravaged North Atlantic
Ever
since winter began to settle in, and the extreme effects of Northern
Hemisphere temperature imbalance and Jet Stream changes began to take
hold, the North Atlantic has become a breeder of extraordinarily
powerful storms. According
to reports from NOAA’s Ocean Prediction Center,
the month of December alone featured 14 instances of hurricane wind
events, 10 storms that experienced rapid intensification, and 5
storms that featured pressures of 950 mb or lower.
For
comparison, a tropical storm that hits 950 mb is usually a category 5
hurricane. And for any ocean basin to show 14 instances of hurricane
force winds let alone 5 950 mb and below storms over a one month
period is extraordinary indeed. Imagine if the south Atlantic
generated 10 hurricanes 5 of which were cat 5 in just one month and
then you get a general comparison.
Two
of these storms were particularly intense with one reaching 940 mb
and another deepening to an exceptionally low 929 mb (the lowest
reading ever recorded for the North Atlantic was 916 mb). By
comparison, the freakish monster that was Hurricane Sandy bottomed
out at 940 mb.
It
is worth noting that the storms of the North Atlantic typically
spread their energy out over larger areas than a tropical system. So
though pressures are low enough to be comparible with the most
intense tropical storms, the winds generated typically ranged from 75
to 100 mph while extending outward over hundreds of miles. By
comparison, a typical tropical cyclone would have a very intense wind
field within 20 to 100 miles of its center with intensity rapidly
falling off beyond this zone.
Overall,
the North Atlantic sees very few storms of 940 mb or lower, usually
at the average rate of less than one every year. So for two to occur
in the same month is exceptional indeed.
(929 mb low rakes England with hurricane force winds on Christmas Eve, 2013. Image source: Lance-Modis.)
January
also featured an almost endless cavalcade of intense storms rushing
across the North Atlantic with numerous lows bottoming out below 950
mb (NOAA will issue a final tally sometime in February). Meanwhile,
powerful storms developing in the North Atlantic continually pummeled
Europe throughout most of the winter of 2012-2013 resulting in some
of the worst rain and snowfall events ever recorded.
This
recent climate-change driven shift of the North Atlantic into an
increasingly stormy weather pattern may well be a prelude to even
more extreme changes to come. Weather models produced by GISS and
examined by premier climate scientist James Hansen indicate that very
powerful storms arise in conjunction with increasing Greenland melt.
Large pulses of fresh, cold water entering the North Atlantic were
observed to create climate instabilities that resulted in very
powerful storms with frontal systems the size of continents that
packed the punch of hurricanes in the physical model runs. It was the
likelihood that such storms could emerge by or before mid-century
that, in part, spurred Dr. Hansen to write his prescient book — The
Storms of My Grandchildren.
As
noted above, the current Greenland melt outflow averages about 500
gigatons each year. This outflow is already large enough to weaken
the Gulf Stream and set off severe weather instabilities. But with
Arctic warming continuing to amplify and Jet Stream patterns bringing
more and more warm air over Greenland, melt rates may triple or more
over the coming decades, resulting in even more severe weather
consequences. So the extreme storm patterns we see emerging in the
North Atlantic now are likely just a minor prelude when compared to
what we will witness as the years and decades progress.
England
in the Firing Line: Windiest December Precedes Wettest January
Currently
in the direct firing line of these powerful storms are the main
islands of the United Kingdom. Throughout December, England suffered
an almost constant assault of storms. In total, five storms, or more
than one storm per week brought excessive rains and wind gusts in
excess of hurricane force to the British Isles. The results were tens
of thousands of power outages, major waves and storm surge events
along the coastline resulting in damage to coastal structures and
persons being swept out to sea, and increasing instances of flooding
over saturated ground.
On
record, December 2014 was one of the stormiest ever seen for the
British Isles. According to weather data, the month was the windiest
since record keeping began in 1969:
In
addition, December also ranked one of the rainiest with many
locations seeing 3 times the normal level of rainfall for the month.
As
the new year began, the series of severe storms impacting the UK
continued unabated through late January. And as of the 28th, South
England had experienced its wettest month since record keeping began
in 1910. With a month and a half still remaining Southeast England
had already experienced its 6th wettest winter season on record.
(Southeast
UK Rainfall from 1910 to present with 2010 easily setting a new
record. Image source: Met
Office)
Dr
Richard Dixon, director of FES Scotland when commenting in a Guardian
interview
about the most recent spate of anomalous UK weather noted:
“November
and December were record breakers in Scotland, with storm after storm
hitting around Christmas. Climate change is bringing chaos to our
weather, not just increasing global temperatures but affecting ocean
currents and global air currents. Scotland is caught between the
changing influences of disappearing Arctic ice, the shifting jet
stream and a weakening Gulf Stream. It is no wonder our weather is
becoming less and less predictable. The consequences for us are more
extreme weather, including more flooding.”
Very
Dangerous Flood Situation for Southeast England: Powerful Storm on
the Way
The
extreme rainfall, as of today, had resulted in a major flood event
for Southeast England focusing on the Midlands and Somerset. The
event inundated croplands, homes and farms throughout the rural
region and spurred England to put its military on standby as
forecasts show more rain and high winds are on the way. The anomalous
event also spurred the 15th meeting of COBRA, the UK’s emergency
response committee which has, increasingly, been called due to a
continuous barrage of weather emergencies.
(Aerial
photo showing homes, businesses and a vast area of land flooded in
Somerset, England. Image Source: David
Hedges)
In
addition to the clearly visible inundation, numerous villages in the
region have been cut off due to flooded roads for more than a week
(with some areas being cut off for a month). The constant barrage of
storms has resulted in both persistently high tides and almost
continuous rainfall. The rainfall, trapped by high sea water, has
nowhere to escape and simply pools, continuing to build up in the
low-lying lands.
The
UK’s conservative government’s response to the situation, thus
far, has been anemic, waiting until today to declare the region a
disaster area.
Unfortunately,
another powerful storm is predicted to arrive by Saturday bringing
with it yet one more spate of strong winds, heavy surf and driving
rainfall to the already soaked region.
(NOAA forecast map for Saturday. Note a powerful 953 mb storm forecast to impact the UK with 70+ mph winds and heavy rainfall. Image source: NOAA’s Ocean Prediction Center)
So
if you’re living in Southeast England please do your best to remain
safe, to heed government warnings, and to urge your government
officials to provide you with the level of response you deserve
during this dangerous time (including policy changes to reduce the
rapidly increasing degree of harm coming from human caused climate
change).
Early
Storms Minor by Comparison
It
is worth noting that, though more intense than we’re used to, these
storms are the early, weaker outliers of a very dangerous period that
is to follow. Our best models and our best climate scientists report
the likelihood of far more dangerous storms emerging from this region
and from the set of conditions that includes a weakening Gulf Stream,
a melting Greenland, an amped up hydrological cycle and rapidly
warming zones first at the northern polar region and then in the
tropics. The eventual size of these storms could expand to cover
continents and involve multiple linked and powerful storm centers. As
noted above, Hansen warned of frontal storms large enough to blanket
continents and with areas of hurricane strength winds stretching
thousands of miles. We haven’t seen anything like that yet. And so
the freakish and extraordinary weather we’ve witnessed this winter,
and in recent years, is merely prologue for worse events to follow.
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