Re: [geo] Article in Toronto Star quoting Jim Fleming and me Hi
Oliver--Yes, but quite possibly the cloud brightening effect would be
far less than the rising concentrations of GHGs over time—you really
need to be doing a comparative analysis.
And then also there is the question of statistical significance. Just
sending this message also created a redistribution of heat that would,
under the butterfly principle, change the weather—the question is if
the statistics are changed significantly or not.
Mike
On 11/15/14 5:09 PM, "Oliver Wingenter" <[email protected]> wrote:
Hi Stephen,
1. Cloud brightening (and any change in albedo) by sea spray or
sulfate particles from DMS will change the heat distribution and
temperature of the planet and therefore the winds.
Best,
Oliver
Oliver Wingenter
Assoc. Professor Department of Chemistry
Research Scientist Geophysical Research Center
New Mexico Tech
Socorro, NM 87801 USA
On 11/15/2014 4:56 AM, Stephen Salter wrote:
Hi All
Engineers who have to design reliable hardware are always
glad to get advice from colleagues which might prevent
mistakes. This advice is particularly valuable if it comes
from people who have read the papers, studied the drawings and
checked the algebra of the design equations.
When I read Jim's comment about Rube Golberg ideas I
immediately sent him a paper on the design ideas, asked him
for technical criticism and offered to send him all my
calculations. He has not got back to me yet but when he does,
and with his permission, I would like to share them around the
community. The more scutiny I can get the less chance of
mistakes. If there is anyone else who can offer help in
spotting potential problems about marine cloud brightening,
please contact me and John Latham.
Alan has done some valuable work with his list of 26 problems
for solar radiation management using stratospheric sulphur.
But there is not much overlap to marine cloud brightening in
the troposphere and I hope he can produce a similar list.
Stephen
Emeritus Professor of Engineering Design. School of
Engineering. University of Edinburgh. Mayfield Road. Edinburgh
EH9 3JL. Scotland [email protected] Tel +44 (0)131 650 5704
Cell 07795 203 195 WWW.see.ed.ac.uk/~shs
<http://WWW.see.ed.ac.uk/%7Eshs> YouTube Jamie Taylor Power
for Change
On 10/11/2014 15:03, Alan Robock wrote:
http://www.thestar.com/news/insight/2014/11/09/many_experts_say_technology_cant_fix_climate_change.html
*Many experts say technology can't fix climate change
*
*There are several geoengineering schemes for fixing
climate change, but so far none seems a sure bet.
*
*By:* Joseph Hall
<http://www.thestar.com/authors.hall_joe.html> News
reporter, Published on Sun Nov 09 2014
As scientific proposals go, these might well be labelled
pie in the sky.
Indeed, most of the atmosphere-altering techniques that
have been suggested to combat carbon-induced global
warming are more science fantasy than workable fixes, many
climate experts say.
“I call them Rube Goldberg <http://www.rubegoldberg.com/>
ideas,” says James Rodger Fleming, a meteorological
historian at Maine’s Colby College, referring to the
cartoonist who created designs for gratuitously complex
contraptions.
“I think it’s a tragic comedy because these people are
sincere, but they’re kind of deluded to think that there
could be a simple, cheap, technical fix for climate
change,” adds Fleming, author of the 2010 book /Fixing the
Sky: The Checkered History of Weather and Climate Control.
/
Yet the idea that geoengineering — the use of technology
to alter planet-wide systems — could curb global warming
has persisted in a world that seems incapable of
addressing the root, carbon-spewing causes of the problem.
And it emerged again earlier this month with a brief
mention in a United Nations report on the scope and
imminent perils of a rapidly warming world.
That Intergovernmental Panel on Climate Change report
<http://www.ipcc.ch/> , which seemed to despair of an
emissions-lowering solution being achieved — laid out in
broad terms the types of technical fixes currently being
studied to help mitigate climate catastrophe.
First among these proposed geoengineering solutions is
solar radiation management, or SRM, which would involve
millions of tons of sulphur dioxide (SO2) being pumped
into the stratosphere every year to create sun-blocking
clouds high above the Earth’s surface.
Anyone Canadian who remembers the unusually frigid summer
of 1992, caused by the volcanic eruption of Mount Pinatubo
in the Philippines a year earlier, grasps the cooling
effects that tons of stratospheric SO2 can have on the planet.
And because such natural occurrences show the
temperature-lowering potential of the rotten-smelling
substance, seeding the stratosphere with it has gained the
most currency among the geoengineering crowd.
One method put forward for getting the rotten-smelling
stuff into the stratosphere could well have been conceived
by warped cartoonist Goldberg.
“You could make a tower up into the stratosphere, with a
hose along the side” says Alan Robock, a top meteorologist
at New Jersey’s Rutgers University who has long studied
SRM concepts.
The trouble is that any stratosphere-reaching tower built
in the tropics, where the SO2 would have to be injected
for proper global dispersal, would need to be at least 18
kilometres high.
Other stratospheric seeding suggestions include filling
balloons with the cheap and readily available gas — it’s
routinely extracted from petroleum products — and popping
them when they get up there.
But Robock says “the most obvious way to go” would be to
fly airplanes up and then spray SO2 into the stratosphere.
Once up there, the sulphur dioxide particles would react
with water molecules and form thin clouds of sulphuric
acid droplets that could encircle the Earth and reflect
heating sunlight back into space.
Placing the cloud in the stratosphere is a must as the
droplets last about a year there while they fall within a
week in the lower troposphere.
Still, the clouds, which would rain sulphuric acid back
down on the Earth’s polar regions, would require frequent
replenishment, with about 5 million tons of SO2 being
needed each year to maintain their reflective capacity,
Robock says.
Due to uncertainties about the droplet sizes that would be
produced by SO2 cloud-seeding, no one is certain how much
cooling the technique would create.
“We don’t know how thick a cloud we could actually make
and how much cooling there would be,” Robock says.
Though he’s devoted much of his career to studying
sun-blocking proposals, Robock is in no way convinced of
their merits.
“I have a list of 26 reasons why I think this might be a
bad idea,” he says.
Chief among these is that the cooling produced by SRM
would be uneven around the globe, with the greatest
temperature drops being seen in the tropics.
“And so if you wanted to stop the ice sheets from melting
. . . you’d have to overcool the tropics.”
The scheme would also produce droughts in heavily
populated areas of the world such as the Indian
subcontinent, he says.
“Another thing on my list is unexpected consequences. I
mean, we don’t know what the risks would be. We only know
about one planet in the entire universe that sustains
intelligent life. Do we want to risk this one planet on
this technological fix?”
Though SRM thinking still centres on sulfates as the best
cloud-seeding compounds, some are now looking at
manufactured nanoparticles to send into the stratosphere,
meteorological historian Fleming says.
“There’s some talk about designer particles . . . but I
don’t know of any production stream, and that would make
it much more expensive.”
The second major proposed geoengineering strategy to
combat global warming is based on carbon dioxide (CO2)
removal.
This could take place either at large sources of CO2 such
as power plants or from the air itself, where even at
today’s climate- threatening levels, it exists in low
concentrations of about 400 parts per million.
Know variously as carbon dioxide removal (CDR) or carbon
capture and sequestration (CCS), there are several
strategies being discussed.
All the plans, however, would likely entail huge costs,
the use of dangerous chemicals and uncertain storage
prospects, Fleming says.
“There are chemical means that would use some very
alkaline, harsh chemicals.”
He notes that there are also thermodynamic means — kind of
the way they make dry ice and they just suck it out and
condense it (into a liquid or solid).”
But thermodynamic removal and compression techniques,
Fleming says, are prohibitively expensive and require the
use of large amounts of carbon-producing energy.
This is largely due to the increased weight carbon
acquires by combining with oxygen during the burning process.
A ton of coal, for example, produces more than three tons
of carbon dioxide because of the added oxygen load,
Fleming says.
“To make it really effective you’d have to have about a
30-per-cent increase in world energy use. But it would
have to come from renewable (sources), which are not in
the offing right now.”
Other removal plans would employ membrane filters that are
permeable to all the air’s component molecules except carbon.
“This seems viable on a small scale, but the question is,
as in all these projects: how do you make it a very large
and very viable and economically feasible?” Fleming says.
Most plans would see the captured CO2 turned back into a
burnable fuel by removing the oxygen component, or have it
condensed into a liquid form and pumped into underground
caverns or ocean trenches.
But the fuel idea would also requite massive energy inputs
to crack the molecule into its two elements, and the
storage scheme would likely produce leakage.
Others are proposing to turn the captured carbon into
charcoal by burning it in oxygen-free fires and burying it
underground for soil enrichment.
“The problem with that one is the scale,” Fleming says.
“The topsoil of the world is not large enough to capture
all the carbon of industry.”
Climate altering schemes go back to at least 1841, when
pioneering U.S. meteorologist James Pollard Espy
<http://www.encyclopedia.com/topic/James_Pollard_Espy.aspx>
published
a rather ruinous proposal.
“He observed that oftentimes it rained after giant fires,”
Fleming says. “So he thought, well, maybe we can stimulate
artificial rains by lighting the Appalachian forests all
the way down the east coast of the U.S. and then the
westerly winds would bring the rains across the eastern
seaboard.”
--
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