Dear John - Had you a technique that worked securely, quite a few
people might sleep better at night. But Ken once accused you, if I
remember correctly, of "making reckless statements," and since you
don't have such a technique, trying to speak in ways that
intentionally builds a feeling of dependency on non-existent
technologies to be deployed 9 months from now would seem to count as
such.
I find it somewhat frustrating, because what you seem unwilling to do
is the >2,000 year old political strategy of "divide and conquer" as
applied to climate strategy (you're not alone in this, I might add),
since whenever you want to create this feeling of complete dependency
upon geoengineering for the near-term, you tend to revert to speaking
of "emissions" as a single lump phenomenon, and therefore hopeless,
when in fact it is virtually unquestionable that if your concerns are
really so immediate, there are 100s of shovel-ready, very practical
projects involving SLCF emissions, that no one in the world is opposed
to in principal, that are vastly under-appreciated by so many people,
and that you could be helping to accelerate enactment of, which could
take out some forcing from the Arctic more quickly than anything else.
We don't really know just how much "cooling power" would be needed to
significantly improve Arctic conditions for the near-term. There's
virtually a 100% chance that what I mention would help, though, and
might even work better than has been projected already in the
literature (i.e., in the UNEP BC/O3 study, etc.). That's because, I
believe, the implications of the recent Cowtan & Way material is very
significant to the concerns of your group AMEG, but you've paid little
attention to it. What I mean is, there's a very close correspondence
of timing between the so-called warming "pause" and an increased
acceleration of Arctic amplification - so poorly recorded in the
primary data sets as to virtually get rid of the pause entirely once
it is corrected (see discussion at Real Climate), which to my mind has
all sorts of potential implications about the causes of what we see
happening in the Arctic - how much is internal feedbacks, how much
comes from rather rapid changes in oceanic/atmospheric circulation,
etc, and this in turn has implications for the Flanner papers that you
have so often depended upon to estimate how much "cooling power" would
be needed to help the Arctic. In short, Jim Hansen has often said that
one of hardest things is to tell a forcing from a feedback, and I
think you would need to get that straightened out first before making
such an estimate correctly....
But in the meantime, I'd just suggest concentrating a lot more on the
things that we already are certain will work, even if they clearly
can't "solve" the problem (which, needless to say, geoengineering
alone couldn't either, even if you had that technique all ready to go....)
Best,
Nathan
On Sun, Aug 17, 2014 at 2:46 PM, John Nissen <[email protected]
<mailto:[email protected]>> wrote:
Thanks for your response, Nathan, with your concern that SRM
techniques are unready and unproven.
I didn't say anything about which techniques might be used for
cooling the Arctic, or how well they might work, or the
probability of success. If we have no option but geoengineering
to cool the Arctic - if that is the only way to provide enough
cooling power (which we can estimate as in the order of a few
hundreds of terawatts) - then *we have to find a way of doing it*,
or face the risk of complete Arctic meltdown.
To deny the need for geoengineering to cool the Arctic is to risk
self-destruct - like pressing the trigger in Russian roulette
where every chamber may contain a bullet. Are we to rely on IPCC
global climate models which predict that sea ice will last for
decades, when the models have abjectly failed to anticipate
minimum sea ice in 2007 and 2012? Are we to believe that these
minima were just one in a million year events, arising from freak
conditions in the Arctic? Are we to believe that there is no
vicious cycle of warming and melting from albedo loss, when the
sea ice volume is following an exponential trend?
On the other hand, there are two techniques which have a good
chance of working because they are based on well-known natural
phenomena: the cooling from stratospheric haze and the cooling
from cloud brightening.
Re stratospheric aerosol, we know that this can have a dramatic
cooling effect from the eruption of Mount Pinatubo in 1991. We
know that the thickness of the stratospheric haze has recently
increased due to man-made emissions of SO2 puncturing the
tropopause and entering the stratosphere at low latitude. If the
SO2 were injected at suitably high latitude, in the lower
stratosphere, then Brewer-Dobson circulation would take the
resultant haze of fine droplets towards the pole where they would
fall back into the troposphere within a few months. We just need
to determine the optimum latitude and time of year to make the
injection for maximum cooling effect on currents and rivers
flowing into the Arctic. There is no good reason why deployment
could not start in spring 2015, given a stock-piling of SO2 and
suitable fitment of stratotankers.
Re cloud brightening, this can complement the stratospheric
aerosol, because it can be done in specific areas and specific
times. The effect will last weeks rather than months. Thus it
can be finely tuned to provide cooling when and where it's most
effective - providing there are suitable clouds to brighten. As
you suggest, Nathan, SO2 could be used. The use of seawater spray
would be brilliant, but it is still an engineering challenge to
produce the droplets of the right size. If the development were
fully funded, the challenge might be met, ready for deployment in
spring 2016. Why isn't the government putting the necessary
funding into this? The answer is in the meme! The government
thinks that geoengineering to cool the Arctic "would be
premature", because that's what they've been told.
So we should explain the situation to governments and urge them to
fund preparation for deployment for SO2 cooling (both
stratospheric and tropospheric) in spring 2015, and development
and deployment for cloud brightening with salt spray to replace
SO2 in spring 2016. This would be the best possible course of
action to reduce the risk of Arctic meltdown to a minimum. There
is strong scientific evidence that we are heading that way, with
no natural negative feedback in sight.
Cheers, John
On Sun, Aug 17, 2014 at 3:00 AM, Nathan Currier
<[email protected] <mailto:[email protected]>> wrote:
In answering what John Nissen writes, I’d like to try to draw
together various recent conversations at this group – first
I’ll respond a bit here, since John was sending this my way,
but then will try to continue on another thread. Basically, I
consider what John writes to itself contain unwittingly one of
the key 'false memes' of geoengineering for Ken's
consideration. The basic problem is much the same in what John
writes as in what Andrew was complaining about in his
“govern-nonsense” thread, deriding its pernicious effects and
describing the need to get back to the basic science, which I
agreed with strongly.
The ‘meme’ was a concept of Dawkins meant to parallel the gene
in the realm of ideas, so a ‘false meme’ is a bit like a
virus, and people can easily spread one around unknowingly.
The really pernicious thing about all the talk about
governance with geoengineering is that it creates the false
impression, once people get into too many heated arguments
about geoengineering’s side effects, or how it could or
couldn’t be controlled, that it actually exists. That is to
say, that there really is an executable SRM technique already
that actually works. It is self-perpetuating, because the more
that people unintentionally reify that concept, the more they
will argue vociferously, and more or less endlessly, about
whether its side effects are too damaging, if its
disincentives to emissions reductions are too powerful, etc.
All of which hides the clear and honest truth: that no one yet
knows if there is any viable SRM geoengineering technique that
really will work (except Mike MacCracken’s idea of
tropospheric SO2, a small-scale Arctic-only version of which I
suggested to John Nissen and those at AMEG a couple of years
ago, as a derring-do trial study, but they actually had no
interest in it......). It seems clear to me that, although
coming from a far less common position, John is actually
passing around a mutation of the very same ‘virus’, when
saying that we should consider /this/ a fundamental false meme
of geoengineering:
That you can prevent catastrophic meltdown of the
Arctic ice cap without SRM geoengineering to cool the Arctic.
This statement clearly has the intention and effect of
creating the same false assumptions as the “govern-nonsense”
crowd, lending tacit feelings of certainty, given enough
repetitions, as to the existence of some viable SRM technique.
But that is really not the case as of now.
I would like to note that, in a side correspondence with
Adrian Tuck, after discussing the stratospheric H2O issue
recently, I was impressed by how, despite the brevity of our
exchange, he was so completely negative on my question to him
about the ability of an Arctic-only stratospheric SRM to
actually work with any efficacy. Adrian probably has more
expertise on stratospheric dynamics than anyone else who has
been writing about SRM in these threads (he was, if I remember
correctly, Chief Scientist for the Chemical Sciences Division
of NOAA’s ESRL during the height of the ozone hole crisis
period, and thus has a great deal of experience in dealing
with many of the most complex relevant dynamics involved), and
he thinks that arctic-only SRM basically will not work (the
lofting at these latitudes will be found to be quite poor, he
feels.....).
Best, Nathan
Hi Ken,
I hope I am not too late to bring this up.
There are two fundamental memes about geoengineering which
worry me because the leading scientific evidence suggests they
are false:
1. That you can reduce CO2 to a safe level in the atmosphere
(as regards its global warming and ocean acidification
effects) without CDR geoengineering.
2. That you can prevent catastrophic meltdown of the Arctic
ice cap without SRM geoengineering to cool the Arctic.
The first meme is widely promoted in the media, who have the
mistaken assumption that the CO2 level will drop quickly if
you stop emissions, ignoring that the lifetime of CO2 is over
a hundred years (and a proportion over 10k years). One often
sees statements that a strategy of drastic emissions reduction
will reduce the effects of global warming to the extent that
adaptation to the worst effects of climate change will be
affordable. This strategy is encapsulated by IPCC AR5 in a
carbon budget for keeping below 2 degrees C; however this
budget is almost certainly bust already because of
underestimations of climate sensitivity, warming from methane
over 20 years, and albedo loss in the Arctic. Dangers from
continued ocean acidification over decades are ignored in AR5.
The second meme is promoted by IPCC, Met Office and others,
who base their projections of sea ice longevity on models
rather than observations. There is an assumption that natural
negative feedback will mysteriously appear to offset the
forcing from albedo loss, which (between 1979 and 2008)
amounted to 0.45 W/m2 averaged globally according to Mark
Flanner [1]. The scientists claim that the observed
exponential trend of PIOMAS sea ice volume decline [2] cannot
and will not continue, hence the summer sea ice will last for
many decades. The media seem to believe that emissions
reductions can halt Arctic warming and save the sea ice.
Even if these two memes cannot be _proved_ to be false, the
evidence that they might be false is _plausible_, so, on
the_precautionary_ principle, we should be immediately
_preparing_ for geoengineering deployment on the necessary
scale, whilst seeking more evidence one way or the other.
Cheers, John
[1] http://www.nature.com/ngeo/journal/v4/n3/abs/ngeo1062.html
[2]
http://robertscribbler.wordpress.com/tag/sea-ice-melt-by-2016/
On Monday, August 11, 2014 11:18:03 AM UTC-4, Nathan Currier
wrote:
Oh! Could you point me towards those discussions, papers,
etc, describing the mechanism of this?
The volcanic H2O paper I just attached discusses lower
stratospheric warming's role in it, but if true,
what you mention would seem very likely to be
involved.....and provide an example of the kind of thing
I was wondering about.....Nathan
On Monday, August 11, 2014 3:24:47 AM UTC-4,
andrewjlockley wrote:
There's an intrinsic connection as SRM warms the
tropopause
A
On 11 Aug 2014 04:24, "Nathan Currier"
<[email protected]> wrote:
Hi, Andrew - I fully agree, and really
enjoyed your post "SRM interaction with
atmospheric anomalies (plus water)"
of several days ago, which had mentioned the
importance of "folding events."
In this case, I was particularly trying to bring
up whether there might be evidence sitting right
in front of us coming from
Pinatubo itself, but perhaps somewhat obscured
from our thoughts by the "questionable meme" of
Pinatubo as a primary
demonstration of "cooling the planet", that
stratospheric SRM might inherently contain
forcings of opposing signs - such
that its radiative effects would always be the net
effects of both negative and positive forcings
from its various dynamics.
Folding events could potentially get messy with
geoE, but I don't think one could say there's any
intrinsic connection
(at least I haven't heard of one).
If it were true that both + and - forcings are
always there with this kind of SRM, it might of
course still work, but this should lower our
confidence
level in the concept's ultimate viability
considerably, because as I say, you'd really have
to keep track of all slight but longer-term
positive radiative
signals it is putting into the climate system
(i.e., cooling the stratosphere, warming
us), since you certainly need some degree of
prolongation for the technique
to have much value......and of course, these are
just the kinds of things where we currently seem
to know quite little.........
Cheers,
Nathan
On Sunday, August 10, 2014 5:17:04 AM UTC-4,
andrewjlockley wrote:
Great point, Nathan. However, you're ignoring
an additional issue. Warming of the tropopause
means it's easier for water to convect or fold
in to the stratosphere. This is a potentially
serious problem, and one I put on the list of
unknowns already.
Bulk air movements also bring more methane
into the stratosphere, which ultimately end up
as water.
My view is that we need urgent improvements in
our ability to monitor and model the
tropopause, if we are to have a hope of making
SRM predictable and safe.
A
On 10 Aug 2014 04:39, "Nathan Currier"
<[email protected]> wrote:
One very widespread geoengineering 'meme'
concerns stratospheric SRM and Pinatubo.
One reads about it continuously - "like
Pinatubo," we will “cool the planet”
through stratospheric aerosols. How real
is this? Pinatubo clearly cooled the
planet /initially/, but are we sure
–really sure –that it cooled the planet at
all temporal scales? When you turn on a
conventional coal plant, it, too, “cools
the planet”, if you care to look only at
the initial response.
There is no discussion, as far as I
remember, on the causes of the increased
stratospheric water vapor changes in
Solomon et al 2010 that I brought up
recently at this group, a paper suggesting
considerable climate warming from
increased stratospheric H2O. In the
attached paper, there’s discussion of how
volcanic eruptions might impact
stratospheric water vapor, causing a pulse
of increased water vapor over 5-10 years.
Although the volcano injects water vapor
itself, its initial impact is actually to
/dry/the stratosphere, since the SO2
reaction uses up so much water vapor,
meaning that the much longer pulsed
increase must come from perturbations in
the stratospheric chemistry/climate
itself. One question I wonder about is how
intrinsically tied to the sulfur itself
these H2O pulses might be, perhaps because
of changes in methane oxidation, of the
kind I was hypothesizing before? In the
paper, the modeled increased forcing
ofroughly +.1w/m2might seem modest,
compared to the initial large negative
forcing of –3w/m2 or so, but one lasts a
year, the other possibly a decade, and how
accurate are these modeled estimates? It
is clearly far easier to recognize the
sudden cooling from the eruption when it
takes place, than a slight warming signal
persisting through a much longer period of
time in an already warming climate system.
Yet clearly this is vital to understand if
anyone is going to be doing useful
geoengineering based on this.
It’s interesting that in the Solomon the
water vapor increase is noted to have gone
into a considerable decline around
2000-2003, around a decade after Pinatubo.
Further, it is important to note that the
complex dynamics leading to these
entangled positive and negative forcings
from a single pulse will almost certainly
be shifted by the sheer act of continuous
prolongation inherent in geoengineering,
so the constant Pinatubo meme becomes a
little....empty?
Cheers, Nathan
On Tuesday, August 5, 2014 2:38:34 PM
UTC-4, kcaldeira wrote:
Folks,
I am supposed to give a keynote talk
at CEC14 in two weeks. For this talk,
I would like to try to develop a list
of oft-cited memes that many assume
are established facts, but which may
not in fact be true.
I am thinking of things like: "With
solar geoengineering, there will be
winners and losers." "Termination risk
is an important reason not to engage
in solar geoengineering." "Solar
geoengineering will cause widespread
drying."
I don't want to discuss all of these
things here but simply to develop a
list. You could help me by sending an
email answering the questions:
2a. What memes are out there which
many "experts" regard as
well-established facts but which in
fact might not be correct?
2b. Why do you suspect the correctness
of that meme?
2c. (optional) Can you provide a
citation or a link to where someone is
assuming the meme is true?
Thoughtful responses would be most
appreciated. If you want to start
discussion about a meme, please do so
in a separate thread so that this
thread can be easily used to develop a
list.
Thanks,
Ken
_______________
Ken Caldeira
Carnegie Institution for Science
Dept of Global Ecology
260 Panama Street, Stanford, CA 94305 USA
+1 650 704 [email protected]
http://dge.stanford.edu/labs/caldeiralab
https://twitter.com/KenCaldeira
Assistant: Dawn Ross
<[email protected]>
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