Thank you
Doctor Morrow for sharing your paper with me.
It is very enlightening, I agree with the arguments against the
deployment of Solar Radiation Management and against research under the premises you present, they make a lot of sense to me.
As you can
see in my profile information, I am opposed to geoengineering the climate, especially
by what I deem intrusive means, such as SRM and ocean fertilization. Other
forms of GE even though controversial, do not raise the hairs on the back of my
neck as these two do.
In relation
to my blog entry originally in English:
“Geoengineering
self-fulfilling prophesies and other rendered moot arguments against research.”
Leaving intentionality
aside for a moment, I think that a process is already happening with the aviation contrails
that is very similar in characteristics to what some conceptual SRM regimes would look like i.e.
whitening of the sky, sulfur aerosol seeding of cirrus clouds, etc. I firmly believe that these 'persistent contrails' and cirrus should be studied, under a geoengineering outline to ascertain if they also
share with SRM some of its more nefarious consequences i.e. ozone depletion,
drought, floods, etc.
I imagine these studies, unlike typical geoengineering, would be based on the premises of
‘curiosity-driven scientific research’, precaution and general investigation. Not
with a future deployment, military or commercialization in mind as the eventual goal line. This would mean no “slippery slope”, "no doing
and enabling", or allowing, and no "double effect".
I think both the 'fire and the flood are already going on'. The chances of the 'fat spelunker' were greatly reduced by ignorance.
I have to
say that it may be naive to think it. But I do:
“So perhaps those in the GE community who are
genuinely opposed to geoengineering should revise their premises and call for
research into GE with the purpose of ending this ‘unintended', but failed and
still ongoing experiment.”
Best regards,
Oscar Escobar
Lakeland, FL
Starting a
flood to stop a fire? Some moral constraints on solar radiation management
Some moral constraints on SRM—DRAFT SEP. 2012
Other reading:
Effects of aircraft on aerosol abundance in the upper troposphere
G.V.Ferry • , R.F.Pueschel •õ , A.W. Strawa • , Y.Kondo 2, S.D.Howard 3, S.Verma 4, M.J.Mahoney 5, T.P.Bui •, J.R. Hannan 6, H.E.Fuelberg 6.
"Aircraft jet engines directly emit aerosols and condensable gases, such as water vapor (H20) and sulfur dioxide (SO2) which lead to the formation of new liquid (volatile) sulfuric acid (H2SO4), particles in the early plume by gas-to-particle conver- sion (nucleation) processes.
Soot aerosol formed during incom- plete fuel combustion constitutes part of the nonvolatile particle fraction.
The newly formed particles grow by condensation and coagulation amongsthemselves and with the background aero- sol."
http://www.researchgate.net/publication/237445161_Effects_of_aircraft_on_aerosol_abundance_in_the_upper_troposphere
http://www.researchgate.net/publication/237445161_Effects_of_aircraft_on_aerosol_abundance_in_the_upper_troposphere
An overview of geoengineering of climate using stratospheric sulphate aerosols
Philip J Rasch1*, Simone Tilmes1, Richard P Turco2, Alan Robock3, Luke Oman4, Chih-Chieh (Jack) Chen1, Georgiy L Stenchikov3 and Rolando R Garcia1
" It is well established that ultrafine sulphate particles are generated copiously in jet exhaust streams during flight (e.g. Fahey et al. 1995). The particles appear to be nucleated by sulphuric acid on ions (hereafter chemiions, e.g. Yu & Turco (1997, 1998b)) formed in the combustion process of jet engines by radical reactions. Sulphuric acid is a by-product of sulphur residues in the fuel (typically less than 1% sulphur by weight); most of this fuel sulphur is emitted as SO2. The fraction emitted as H2SO4 decreases as the fuel sulphur content increases, and accounts for roughly 2 per cent of the total sulphur as the fuel sulphur content approaches approximately 1 per cent."
Geoengineering
by stratospheric sulfur injection and volcanic analogs: Applications for a 3-D
chemistry-climate model with aerosol microphysics
Debra
Weisenstein, AER, Inc.
Added Oct. 18 2013
Soot and Sulfuric Acid Aerosol from Aircraft: Is There Enough to Cause Detrimental Environmental Effects?
02/2004; DOI:10.1016/S0021-8502(98)00192-X
Pueschel,
R. F. (NASA Ames Research Center; Moffett
Field, CA, United States);
Strawa, A.
W. (NASA Ames Research Center; Moffett
Field, CA, United States);
Ferry, G.
V. (NASA Ames Research Center;
Moffett Field, CA, United States);
Howard, S.
D. (NASA Ames Research Center; Moffett
Field, CA, United States);
Verma, S. (NASA Ames Research Center; Moffett
Field, CA, United States)
Abstract:
Aerosol
from aircraft can affect the environment in three ways: First, soot aerosol has
been implicated to cause Icing-tern ozone depletion at mid-latitudes in the
lower stratosphere at a rate of approx. 5% per decade. This effect is in
addition and unrelated to the polar ozone holes which are strongly influenced
by heterogeneous chemistry on polar stratospheric clouds. Second, the most
obvious effect of jet aircraft is the formation of visible contrails in the
upper troposphere. The Salt Lake City region experienced an 8% increase in
cirrus cloud cover over a 15-year period which covariates with an increase in
regional commercial air traffic. If soot particles act as freezing nuclei to
cause contrail formation heterogeneously, they would be linked to a secondary
effect to cloud modification that very likely is climatologically important.
Third, a buildup of soot aerosol could reduce the single scatter albedo of
stratospheric aerosol from 0.993+0.004 to 0.98, a critical value that has been
postulated to separate stratospheric cooling from warming. Thus arises an
important question: Do aircraft emit sufficient amounts of soot to have
detrimental effects and warrant emission controls? During the 1996 SUCCESS
field campaign, we sampled aerosols in the exhaust wake of a Boeing 757
aircraft and determined emission indices for sulfuric acid (EI(sub H2SO4) =
9.0E-2 and 5.0E-1 g/kg (sub FUEL) for 75 and 675 ppm fuel-sulfur, respectively)
and soot aerosol (2.2E-3 less than EI(sub SOOT) = l.lE-2 g/kg (sub FUEL)). The
soot particle analysis accounted for their fractal nature, determined
electron-microscopically, which enhanced the surface area by a factor of 26 and
the volume 11-fold over equivalent-volume spheres. The corresponding
fuel-sulfur to H2SO4 conversion efficiency was 10% (for 675 ppmm fuel-S) and
37% (for 75 ppmm fuel-S). Applying the H2SO4 emission index to the 1990 fuel
use by the worlds commercial fleets of 1.3E11 kg, a conversion efficiency of
30% of 500 ppmm fuel-S would have led to an annual contribution to the
atmospheric sulfur budget by aircraft of 2.E7 kg H2SO4. This is about one part
in 1.E4 of anthropogenic sulfate from other sources. The soot emission index
given above yielded a 1990 injection of soot aerosol by aircraft of 1.E6 kg.
Thus, soot amounts to only five percent of the aerosol generated by aircraft.
Its reactivity with ozone would have to be 20 times that of sulfuric acid
particles to make it chemically significant. Nevertheless, the findings, of
stratospheric soot loadings commensurate with aircraft fuel consumption, based
on the emission index given above and the assumption of stratospheric residence
times of the order of one year implicate aircraft as stratospheric polluters. A
trend similar to soot of H2SO4 aerosol loading could not be deciphered, neither
from in situ measurements nor SAGE II satellite extinction, against the
"noise" due to volcanic eruptions. Observation of soot particles at
20 km altitude which, if emitted by aircraft were generated at 10-12 km
altitude, suggests a displacement of those particles against gravity. Because
eddy mixing is virtually absent in the lower stratosphere and isentropic mixing
explains lofting to only about 15 km, radiometric forces acting on
morphologically and chemically asymmetric soot particles must be considered a
possibility. The consequence could be an extended residence time of soot
against that of sulfuric acid aerosol that would lower the single scatter
albedo with time.
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