Posts
Another
Arctic cyclone brewing
Sam
Carana
7
August, 2013
Another
cyclone is brewing in the Arctic. Below are Naval Research Laboratory
projections of sea ice drift a few days ahead.
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The
image below, from Danmarks Meteorologiske Institut (DMI), shows
surface pressure over the Arctic Ocean on August 7, 2013.
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Below are two projections of pressure and wind direction for August 11 and August 15, 2013.
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edited
screenshots from animation at weather-forecast.com
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More
will be added at this post soon.
Climate
Monsters We Want to Keep in the Closet: Heinrich Events, Superstorms,
and Warming the Deep Ocean
7
August, 2013
“Think
of the climate change issue as a closet, and behind the door are
lurking all kinds of monsters — and there’s a long list of them,”
— Steve Pascala.
***
It
has been said that Nature is a serial killer. Within her vast
managerie of life, climate, and the physical world, there are many,
many terrible processes that could mortally impact individuals,
larger groups, entire species and even families of species. And if
you were to look for the means by which Nature performs her worst
violence, the mass extinction events, your eyes would almost
immediately settle upon the uncomfortable issue of climate change, an
issue all too relevant today.
Of
twelve major mass extinction events identified in past geological
epochs, ten were likely caused by climate change. Marked by layers of
rocks almost entirely devoid of complex life, these periods in which
Earth became little more than a tomb should serve as a stark warning
against our own rapidly increasing insults to Earth’s climate. The
very worst of these ‘tomb epochs,’ the Permain or ‘Great Dying’
in which 90 percent of all species went extinct was clearly caused by
a series of worsening insults brought on by a terrible switch in
climate brought on by a raging global warming nightmare. And though
the Permian Extinction raged about 200 million years ago, it has some
rather disturbing similarities to today. For one, it was an era in
which a cold glacial period emerged into a far warmer period. And
secondly, a large greenhouse gas emission source forced warming to
drastically accelerate resulting in not one but three major
extinction crises over the course of about 165,000 years. It was the
worst of the worst of all tomb epochs and it was most likely set off
by a massive chain of events brought on by very rapid warming.
Scattered
across the wreckage of the Permian and these other tomb epochs are
the foot prints of the three climate monsters from Pascala’s horde
that we most definitely do not want to unleash. Monsters we are
through our current actions and choices, even now, causing to stir.
Three
to Keep Behind the Door
Human
beings, through their carbon emissions, risk prodding the very worst
monsters in Nature’s death brigade to awaken — the ones that set
off previous mass extinction events through a combination of terrible
weather, unleashing carbon stocks sequestered over millions of years,
and, eventually, turning the ocean into an enormous killing machine.
These three, worst of the worst, climate monsters which we most
certainly want to keep behind Pacala’s door are: Heinrich Events,
Rapid CO2 and Methane release, and Anoxic and Canfield Oceans. Though
these three are identified here as separate catastrophic events, they
are related in that they can set in motion a chain of
self-reinforcing effects that may enhance the likelihood for the
other events to occur. They also unleash a set of more minor but
still terrible associated difficulties.
In
this particular blog, I’ll explore the first and arguably mildest
of these catastrophes — Heinrich Events.
Pulses
of De-glaciation
As
Earth moved through its far more milder, nature-caused, phases of
glaciation and deglaciation, previous warm phases often resulted in
sudden surges of ice burgs and melt flows from the Earth’s ice
sheets. Large pulses during warm trends set off armadas of these
maritime brutes which flooded the ocean, causing drastic consequences
to weather and climate.
The
ice burgs unleashed during these warming-induced pulse events were
enormous floating collections of rock and ice. As they melted, the
glaciers disgorged the rocks frozen in their bellies, leaving layers
of pebbles littering the sea floor and creating a record of their
passage. Hartmut Heinrich was the first to describe these events. So
now they bear his name.
Greenland
and West Antarctica: Gateways For the Heinrich Monsters
In
the emergence from the last ice age, it is thought that sudden melt
pulses from the vast but now entirely melted Laurentide ice sheet
resulted in the majority of these events. Since only the ghost of
this ice sheet remains in the form of a thin patina of frozen tundra
over the Northern Hemisphere’s Arctic regions, there is no longer
any risk for Heinrich melt and ice burg pulse events from this now
ephemeral source.
But
the great Greenland and West Antarctic ice sheets remain. Greenland
is a vast store of ice. Nearly two miles high at its center, it
contains enough ice to raise the world’s sea levels by 23 feet.
West Antarctica is yet one more great pile of ice. In total, if the
two were to melt together, they could contribute as much as 75 feet
of sea level rise.
But
these melt events, as we see the in the geological past, don’t
happen neatly. The great glaciers sit mostly still for long, boring
periods and then they surge in brief, catastrophic instances
unleashing massive flows of both water and ice burgs. Heinrich
Events.
Alone
or together, Greenland and Antarctica bear more than enough ice to
set off this particularly nasty brand of climate induced catastrophe.
The
Human Forcing is Far More Brutal
In
the past, a slower build up of heat set off by the warm phase of
gradual orbital cycles eventually passed tipping points that led to
rapid ice sheet disintegration and related melt-pulse Heinrich
Events. Today, the human greenhouse gas forcing is far, far more
powerful. At the last ice age’s end, a combined forcing of about
100 parts per million of additional CO2 and the steady but ever so
slight forcing caused by the warmer orbital cycle was enough to set
off these powerful events. Today, CO2 has risen by 120 ppm and
continues to rise by 2-3 parts per million each year even as other
rising greenhouse gasses, primarily methane, add an additional 28% to
this strong and growing forcing.
It
could easily be argued that the human forcing surpassed that of a
natural forcing powerful enough to end an ice age sometime last
century. But the ice age is already done and so we head into mostly
uncharted territory only vaguely hinted at in the deep geological
past. The current pace and path of increased forcing makes a bad
situation worse as a CO2 rise to at least 480 ppm is predicted by
mid-century. Business as usual end century estimates come in at the
catastrophic level of 800 ppm or more of atmospheric CO2 with an
unknown additional amount of methane and related greenhouse gasses.
The
Greenland Ice Sheet is Starting to Slip
Unfortunately,
it seems we may have already begun to let one Heinrich monster off
its leash. For reports coming in over the past decade show that the
vast two mile high Greenland ice sheet is starting to slip.
Under
the current and ever-rising insult of the human climate change
forcing, the Greenland ice sheet is sagging and deforming, filling
with melt ponds and flows that flush through to its base, and, most
ominously, monstrously grinding toward the ocean at an ever
increasing pace. Research conducted by Arctic scientists shows that
the ice sheet’s speed is increasing by a rate of about 2-3 percent
per year. This speed of increase results in the disgorging of vast
volumes of ice burgs and melt waters into the North Atlantic. An
average of about 500 cubic kilometers of ice burgs and melt waters
are now flowing into the ocean from Greenland alone. But with the
pace of ice sheet melt and movement picking up, we are, sadly, only
at the beginning of what appears to be a very risky situation.
Flotillas
of Ice Bergs Riding a Tsunami Like Melt Pulse
Let’s
step back for a minute from this slow motion disaster that we’re
both the cause of and captive audience to and consider, for a moment,
the structure of Greenland’s ice and land mass. The Greenland
coastline is little more than a honeycomb of semi-frozen channels
both coming into contact with the larger water bodies of Baffin Bay
and the North Atlantic and drilling deep into the interior of
Greenland itself. The two mile high glacier slopes gradually down
toward and into these hundreds of channel estuaries, creating a slope
defined by tall ice sheets terminating in low, ocean-opening
waterways.
(Image
source: Lance-Modis)
In
the above image, you can see just one section of these ice channels
that encompass almost the entire coastline of Greenland. Note the
dark ocean water coming into contact with the silver-white of
Greenland ice. The small white flecks you can see in this Modis shot
are nothing less than immense ice burgs riding the winds and tides
out into the North Atlantic. If you accurately imagine the entire
coast of Greenland perforated by such outlets, what you come to
realize is that Greenland is nothing less than an enormous ice burg
dispersal mechanism. One that, if it really cranks up, will disgorge
vast flotillas of ice bergs riding out upon tsunami-like melt pulses
in every direction.
Inherent
to this potential is the fact that Greenland ice is continuously in
motion. Pulled by gravity, the towering ice sheets constantly seek
the sea. Slowly grinding away, the ice moves gradually, steadily
until it, at last, finds water, there it explodes in a riotous
calving of the immense and monstrous ice burgs. The more solid and
cold Greenland becomes, the slower its ice moves toward the ocean.
The ice sheet weight increases, depressing the entire island into the
crustal plate and keeping more of its ice locked in the center. The
ice forms more solid boundaries to other ice flows and the ice
grinding slows as it thickens. But the more wet and warm the ice
becomes, the opposite is true. Water flows through the ice sheet to
lubricate its base, the large pools of water on top further heat and
deform the ice, the crustal plates rebound, pushing the island higher
and adding gravity as a more and more powerful force attracting ice
to ocean, and increasingly large pulses of melt water flush out from
the center of the glaciers, drawing both ice and water along in ever
greater volumes toward the ocean.
In
a Heinrich Event, the melt forces eventually reach a tipping point.
The warmer water has greatly softened the ice sheet. Floods of water
flow out beneath the ice. Ice ponds grow into great lakes that may
spill out both over top of the ice and underneath it. Large ice damns
may or may not start to form. All through this time ice motion and
melt is accelerating. Finally, a major tipping point is reached and
in a single large event or ongoing series of such events, a massive
surge of water and ice flush outward as the ice sheet enters an
entirely chaotic state. Tsunamis of melt water rush out bearing their
vast floatillas of ice burgs, greatly contributing to sea level rise.
And that’s when the weather really starts to get nasty. In the case
of Greenland, the firing line for such events is the entire North
Atlantic and, ultimately the Northern Hemisphere. But the Southern
Hemisphere has its own set of troubles to contemplate. For there
resides the seemingly endless pile of ice that is Antarctica.
Storms
of My Grandchildren
A
long time ago, I read a book called “The Coming Global Superstorm.”
The book trivialized the potential effects of Heinrich Events by
lumping them into a myopic and artificial single instance that the
authors referred to as a Superstorm. The book was also chock full of
astrological New Age jargon and other unrelated philosophy that
greatly discredited the authors’ notion of Superstorm. Even worse,
Hollywood jumped onto the trivialization bandwagon by producing the
entirely unrealistic movie “The Day After Tomorrow.”
About
this New Age book and its related Hollywood film, I have but one
thing to say — if only it were so easy. Both the book and the movie
boil the risk of human caused global warming into a single, linear
event, which ends in single results. Even worse, both the book and
the movie produce the false impression that such storms will result
in an ice age. Again, if only it were so easy.
If
you want to learn about the potential involved in such events, you
should become a student of climate scientist James Hansen. You could
start by reading the excellent book “Storms of My Grandchildren”
and you could continue by reading his papers pertaining to extreme
weather caused by West Antarctic and Greenland Ice melt.
What
Hansen describes in his later work is the potential for ‘continent
sized frontal storms
packing the punch of hurricanes’ to rip across vast swaths of the
Northern Hemisphere in association with an extreme weather pattern
set up by a Heinrich type event acting in combination with a human
warming induced heat amplification of the tropics. In vast difference
to the “Day After Tomorrow,” these storms are not single
instances, but potentially re-ocurring catastrophic weather hazards.
How
bad could these storms get? As an example, the freak hybrid
superstorm Sandy is but a prelude to the main events.
Yet
Sandy’s somewhat unique hybrid structure and location may well
provide us with hints as to the nature of future superstorm events.
What we see in the above NOAA satellite shot is a storm that is
linked both in the tropics and in the Arctic. The storm derives
energy from a cold air mass over Greenland and pulls in another ‘arm’
of energy from the tropical Atlantic.
During
the Heinrich event, the ice burg cooling effect mentioned by Hansen
in his papers and the human caused heat amplification of the tropics
will set up a far more disastrous atmospheric storm potential. And
the raking effect of continent sized frontal storm systems would have
even more damaging consequences to human infrastructure than the
related pulse of sea level rise alone.
Ocean
Circulation Change to Open the Door for the Hydrate Monster,
Anoxic/Canfield Oceans?
Yet
one more ominous result of Heinrich Events is a high-stress shock to
ocean temperature and saline circulation systems. Such events are
likely to shove the northern termination of larger ocean systems
further toward the equator. The cold, fresh water pulses would result
in less sinking of water at the poles. Related increased heat at the
tropics would begin to set up a system where salty waters begin to
sink there.
Even
more ominously, a wedge of cold water at the surface spreading out
from the poles would push hotter, saltier water toward the ocean
bottom. Fresh water is less dense than salty water, so the fresh
water pulses from glaciers and melting ice burgs will act as a wedge,
driving the denser, warmer, saltier water toward the bottom The net
effect of such changes would be a shallower and weaker ocean
circulation system as more warm water is averted toward the ocean
bottom near the equator and then spreads northward and as warmer
surface waters toward the poles and temperature regions are driven
toward the sea-bed.
Since
vast stores of methane lay locked in hydrates on the sea bed, these
stores are at risk of greater forcing and more rapid destabilization.
To note, the end of the Permian, in which a partially glaciated world
transitioned to a hot house, is estimated to have seen methane levels
at around 11 parts per million — almost ten times the current
level. Large melt pulses are, therefore, a potential mechanism for
ocean bottom heating and increasing rates of methane release.
This
event sets in place conditions that increase risk for the two other
climate monsters — increasing CO2 and methane release from Earth
Systems and the perhaps more ugly anoxic and Canfield Ocean states.
And both we will visit in future blogs.
How
Soon?
How
soon could we see Heinrich type events, Hansen-style superstorms, and
dangerous changes to ocean circulation? Hansen, in “Storms of My
Grandchildren” indicates a risk for such events emerging by
mid-century under business as usual fossil fuel emissions. Jason Box
and others have shown an increasing speed and melt of the Greenland
Ice Sheet occurring during the first and second decades of the 21rst
Century. So it appears we are starting to ramp up to such events even
now as an ominous ice sheet response begins to show on the climate
radar. So the period of risk appears to be sometime between now (low)
through 2070 (moderate to high depending on human CO2 forcing growth
or mitigation).
That
paleoclimate and modeling performed by Hansen show the potential for
such powerful events should be cause for serious concern and reason
for ever-greater urgency in reducing human greenhouse gas emissions
and our related climate risk to the lowest levels possible. And, in
the end, we almost certainly do not want to begin to bring forward
conditions that will release the other two ‘monsters behind the
door’ — rapid CO2 and methane response from Earth Systems and
anoxic and Canfield Oceans.
Links:
It’s
Hotter Up North than Down South: Tundra Fires Erupt Over Canada as
Heatave Pushes to Arctic Ocean Shores
(Image
source: NASA/Lance-Modis)
7
August, 2013
Over
the past week, large tundra fires have been erupting over a section
of extreme northern Canada between the Great Slave Lake and the
shores of the Canadian Arctic Archipelago. With a major Arctic
heatwave predicted as various extreme weather conditions arise, this
region will be worth very close monitoring over the next few days.
The
fires are emerging in a region of the Arctic between 62 and 66
degrees north latitude, near the Arctic Circle. In the image above,
we see the Great Slave Lake in the lower left hand corner, the Great
Bear Lake in the upper center, and Coronation Gulf and Amundsen Bay
bordering the map’s right hand side. The fires are visible, along
with their tell-tale smoke plumes and underlying scorch marks, in a
region between the Great Slave Lake and Great Bear Lake. Terrain type
in the regions burned include boreal forest and tundra.
Weather
conditions over the past two weeks have been both warm and dry for
this Arctic region. But over the past few days, temperatures have
been heating up. As temperatures rose, wildfires sparked and grew.
Forecasts now call for a region of very hot Arctic weather to stretch
all the way to the shores of the Beaufort Sea by Friday with
temperatures likely to exceed 30 degrees C (86 degrees F) over the
broad stretch of land surrounding the Mackenzie Delta.
This
high Arctic heat pulse is being driven north by a powerful high
amplitude wave in the Jet Stream which is setting up very extreme
temperature differentials between the Beaufort Sea and North Canadian
land masses. Temps over the Beaufort are now in the range of -5
degrees C in some areas (about 22 F), with temperatures over land
hovering, at this time, in between 15 and 23 C (60s and 70s) and
predicted to surge as high as 30 C + (86 F+). This amazing
temperature differential is likely also providing fuel to
a powerful 978 mb (Smokey) Arctic Cyclone now traversing from the
Laptev and into the Central Arctic.
It will also intensify winds and drive greater heating over Arctic
land masses over the next few days.
(Image
source: Arctic
Weather Maps)
The
map indicates forecast daytime temperatures for the Northern
Hemisphere land masses bordering the Arctic on Friday, August 9,
2013. Note
the highly anomalous condition in which temperatures are predicted to
be hotter further north, over regions near the Mackenzie Delta, than
they are further south. This is an extraordinary inversion and one
certainly worth putting into the context of the extreme weather
conditions that are now ongoing. (Areas
of red on the map indicate average temperatures in the range of 77-86
degrees (F). Maximum daily values are likely to exceed this average
predicted range.)
Though
not as massive or extensive as
the fires raging across the Arctic Ocean in Russia,
these fires are still quite large — with burn marks stretching 6 or
more miles at their widest point in many cases. Another region just
west of the fires shown in the image above is also experiencing a
very large blaze. This complex of fires is raging along the banks of
the Mackenzie River and is shown to have a fire line more than ten
miles across at its widest point.
(Image
source: NASA/Lance-Modis)
Note
the extremely large scorch mark to the lower center portion of the
map, with a large, energetic fire blazing in the upper right portion
of the map and a smaller, though still substantial, blaze erupting to
the upper left.
As
noted above, fire-conducive conditions for this region are forecast
to intensify well before they moderate. So this particular spate of
fires may well be just starting to ramp up.
For
a final note, I’d like to add the observation that this event
represents a bit of rather harsh irony. These fires now rage in a
region dominated by Canada’s Tar Sands Industry. Carbon is being
baked and burned out of the land and soil by anomalous heat caused by
human warming and not just by the immense grind and crush of fossil
fuel industry. The steps of carbon extraction, in this case, have
been shortened and are now out of our control.
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