Mr Currier's excellent piece in Huff Po calls openly for geoengineering

http://www.huffingtonpost.com/mobileweb/nathan-currier/arctic-climate-change_b_1911550.html

Saving the Arctic Ice: Greenpeace, Greenwashing and Geoengineering Nathan
Currier
Therese's was much media attention a couple of weeks ago when this year's
sea ice extent minimum broke all records: it was down almost 50 percent
from the 1979-2000 average. Little attention, though, accompanied a
possibly even more significant figure, released a few days ago: those who
run the PIOMAS sea ice volume model at the Polar Research Centershowed the
2012 sea ice volume minimum was down almost 50 percent not from decades ago
-- but from 2007! That's right: the volume of arctic sea ice this September
minimum was probably about half of what it was, just back in 2007. This
figure should deeply trouble any reasonable human being, as it strongly
suggests reaching an ice-free arctic sea ice minimum within half a decade,
and, since there is little dispute that some summer sea ice will persist to
the north and west of Greenland for much longer, the first "near-ice-free"
point will likely arrive in just the next few years, as sea ice expert
Peter Wadhams has pointed out, and the London-based policy group and think
tank Ameg has maintained.How should we respond? Greenpeace recently started
a "Save the Arctic" campaign. That's great -- but you can only save the
arctic by saving its ice. And, unfortunately, it is now clear that this can
no longer be achieved through emissions reductions alone. It's too late for
that. Greenpeace held a meeting on the polar emergency in New York City, by
chance on the same day the record extent minimum was called, and while on
the surface it seemed pretty ordinary, it was at heart very odd. Nobody
suggested any change of approach, any specific re-strategizing, to respond
to the accelerating situation. The word emergency was a common currency
passing all lips, but in fact it was unclear whether people were really
speaking the same language, especially as concerns that most precious thing
in emergencies -- time. And there seemed to be no translator in the room,
saying "this is the timescale of this, that's the timescale of that."The
meeting's two scientists, Wieslaw Maslowski (on ice) and James
Hansen (general climate), themselves focusing on somewhat different time
scales, were followed by the 'social/political' panel discussing what we
should do: the panel discussed green energy, solar power, how we shouldn't
move towards nuclear, that kind of stuff. But Jim Hansen had said in answer
to a question (mine), "We aregoing to lose that sea ice," and also said
that to save it, "You could do some quick things." As I'll discuss in my
next post, Hansen meant geoengineering. Greenpeace Director Kumi Naidoo
later couldn't even remember the word -- geoengineering. But if he's going
to save the arctic, I'm afraid he's going to need to know it.A big issue in
whether to consider something an important 'threshold' is its
reversibility, and we will discuss the reversibility of this one further in
the next episode. At the meeting, since Maslowski focused on sea ice
modeling failures, and Hansen on the whole climate picture, many of the
potential immediate physical impacts of allowing this coming ice loss
remained poorly or not at all elaborated -- although they are important for
Greenpeace, and everyone else, to understand, I feel. Hansen showed a slide
of three major tipping points which he said place us in a climate
'emergency,' because one can lose control around tipping points. One was
methane hydrate, for example. But what Hansen didn't show were what I might
dub the 'minor tipping points,' far more immediate changes stemming from
this coming loss, which could make it hard to turn around, and could lead
us straight to those more major ones Hansen fears, in a slippery slope.Keep
in mind that what we're talking about here is losing almost as much summer
ice cover in just the next few years as we have over the lastfew decades,
and that these are all circularly interrelated reinforcing mechanisms.
Sorry, if it seems a bit mind-numbing for some readers, but here's my
list:1. Greatly increased arctic water vapor, increasing arctic warming
(water vapor is a potent greenhouse gas) but also fundamentallyaltering
arctic hydrology and hence weather patterns.2. Immediately
and fundamentally altered arctic atmospheric chemistry, causing increased
arctic methane lifetime, among other basic changes.3. Certain increase in
acceleration of arctic warming, from increased solar energy entering the
arctic ocean (this engenders 1.) and the release of latent heat into the
atmosphere during autumn's rapid re-freezing.4. Consequent increased
potential for large arctic storms like the Great Arctic Cyclone this
summer.5. Consequent increased deep convection events (mixing to bottom) of
arctic ocean, particularly important over the shallow water of the shelves,
where lower layers can now often be methane-saturated.6. Consequently
an increase of seabed methane emissions -- including from seabed
permafrost, shallow methane hydrate, and from thawing of either or both of
these and increased gas migration pathways allowing free gas from
underneath the hydrates to outgas.(For full PowerPoint PDF, scroll down to
Topic/Title Methane Release from Eastern Siberian Shelf.)7. This increase
in seabed permafrost thawing leads to a subsequent increased risk that a
random seismic event could suddenly release large amounts of methane from
the above combination of thawing sources, or from other thawed arctic
carbon stores (see PowerPoint above).8. Increased risk of general
degradation of shallow methane hydrates leading to slope failure and
consequent methane release.9. Certain increase in chronic emissions of
methane (and CO2) from thawing land permafrost, peat, etc. with the general
added warming mentioned above.10. The increased arctic methane lifetime
(2.) is indistinguishable from an increase in its arctic abundance.11.
Increasing continued rate of ice (and snow) loss as the ice-free-period
subsequently lengthens, from all the above, particularly significant as the
insolation increases earlier in the season to around the solstice in June
(discussion here, scroll down to An Ice-free Solstice).And here are some
immediate potential global impacts to chew on:12. Recent research suggests
that ice (and snow cover) loss is at least one causative factor in
recent extreme weather -- drought, flood, fires, etc. -- and if so this
could quickly be amplified.13. Consequently, recent global impacts on food
security could increase proportionally.14. Economic losses from each of
those (12., 13) would probably increase proportionally, and potentially
could amplify into global economic recession or even depression.15. If
there's large-scale (multi gigaton-scale) methane release soon, this would
of course fundamentally alter the whole path of global warming (see
my Twilight posts #1,#2), with vast consequences.16. If the ice-free period
expands significantly, altered arctic tropospheric oxidation could rapidly
start to impact high latitude urban areas, making cities with large
populations rapidly become more difficult to live in (good discussion here
at GISS, where Hansen is himself director).No one said a word at the
Greenpeace meeting, seemingly dismissing it as a major threshold at all. No
one ever said, "Let's fight this." But I am suggesting that you should see
skull and crossbones hanging above this threshold crossing. Like playing
around high voltage wires or train tracks, allowing this threshold to be
crossed will add considerable risk. And I'm suggesting that it will be
crossed in just the next few years, unless we do something about it.As I'll
discuss next time, it might prove much harder to reverse than many assume
within the climate world. Therefore, as Energy Secretary Steven Chu
said about allowing an eventual runaway arctic permafrost carbon feedback,
we must all say loudly now about this initial step onto that vast and
treacherous slippery slope: "We cannot go there!" And if we don't want to
go there, there's now no longer any question -- geoengineering will have to
be part of the remedy.

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