Memorandum 155
Submission from John Gorman, Chartered
Engineer
GEOENGINEERING FOR
ZERO SEA
LEVEL RISE
Summary
1. Sea level will probably rise more quickly
and much more than the IPCC estimate of 40 centimetres by 2100.
2. The implications for London are obvious.
3. No reduction in CO2 emissions can avoid
or significantly reduce sea level rise this century.
4. The only way to control sea level rise
is screening of solar radiation (geoengineering).
5. There is very little geoengineering research
because it is not "politically correct" in the climate
academic community.
6. There are very practical well-defined
research projects in geoengineering that need funding.
7. If shown to be technically feasible there
are very practical proposals for implementation.
1. SEA LEVEL
RISE
1.1 In most of the world there is not yet
much negative effect of global warming. The danger lies in the
Arctic and Antarctic where the temperature rise is about 10 times
as great as that at the equator. Currently it is 3 to 4°
compared with the global average figure of 0.7° (British
Antarctic Survey position statement and IPCC.) The result is very
significant summer melting of Greenland and the Antarctic Peninsula
(which protrude outside the Arctic and Antarctic Circle respectively.)
This summer melting is far greater than has occurred at any time
since the end the last ice age. (British Antarctic Survey)
1.2 Common sense and many anecdotal reports
suggest that this will eventually result in the loss of much of
these two ice sheets. (Not the main body of Antarctica where there
is at present no summer melting.) This would result in a sea level
rise of about 16 metres. The question is how quickly this could
occur. This is obviously difficult to estimate. The predicted
sea level rise in the IPCC report from March 2007 is 40 centimetres
by 2100. This was widely publicised as was the fact that this
figure had been reduced from that in the previous report.
1.3 Where does this figure of 40 centimetres
come from?
In a nutshell it is the actual rise in the decade
to 2003 multiplied by 10 for the 10 decades to 2100. (Which would
give 31 centimetres +7 so 40 is slightly greater.)
This raises two questions:
(i) The average rise in the previous three decades
was 1.4 centimetres per decade. This rose to 3.1 in the decade
to 2003. Is there any reason to believe that subsequent decades
in the century will stay at four centimetres per decade? Isn't
it far more likely that there will be a rapid escalation as temperatures
rise?
(ii) These are still small rises resulting from
an increase in the same mechanisms, such as surface water runoff
in summer, which are occurring today. Can we have any confidence
that much more dramatic events will not occur such as rapid glacial
acceleration following ice shelf breakaway? These are mentioned
in the IPCC report but no allowance is made for them in the "executive
summary figure" of 40 centimetres.
1.4 Many such possibilities are considered
in the report (chapter five IPCC2007) and the difficulty in prediction
is frequently mentioned. This difficulty in prediction is exemplified
by the loss of Arctic Sea ice in summer. The IPCC median prediction
was only a 22% loss by 2100 in the report published in March 2007.
This figure was actually equalled in the summer of 2007! Many
are now predicting total loss of Arctic summer sea ice as early
as 2013-more than century earlier than the IPCC prediction. This
loss of reflectivity (albedo) in the whole of the Arctic Ocean
is obviously of enormous importance to the survival of the Greenland
ice sheet.
1.5 It seems irresponsible of the IPCC to
allow such credence to be given to the figure of 40 centimetres.
It would have been far better to say "we cannot predict sea
level rise". The New Scientist suggested in the issue of
10 March 2007 that there was political pressure to stop any alarmist
comment or figure being included. (See page 9-Copy of leader page.)
1.6 The truth is that, with the summer melting
that is occurring in Greenland and the Antarctic Peninsula, and
the loss of the Arctic Sea ice we haven't a clue how much or how
quickly sea level will rise. If it is a slow and progressive rise,
but quicker than we plan or build for, then the problems will
always arise with a combination of high tide and exceptional storm
as demonstrated in Burma recently. The same combination resulted
in the flooding of New Orleans, of the English east coast in 1953
and very nearly of Rotterdam and London only last summer. The
flood defences in Rotterdam would have been overwhelmed by another
six inches of storm surge.
1.7 When you look at the man-millennia that
went into the evaluation of sea level rise worldwide from 1960
to 2003 it seems to be a bad case of "not seeing the wood
for the trees" to allow the results to be extrapolated to
2100.
2. LONDON
2.1 It seems unnecessary to point out how
susceptible London is to any sea level rise, which is not predicted
or which occurs more quickly than new sea defences can be erected.
2.2 Sea level rise could be almost instantaneous.
The Nobel laureate economist Thomas Schelling, in his lecture
to the World Bank, mentions one particular ice shelf in Western
Antarctica but there are many such examples. Because this ice
shelf is resting on the bottom of the ocean it will result in
sea level rise if it breaks away as is happening to so many bits
of ice shelf in both Antarctica and the Arctic.
2.3 In the lecture, Thomas Schelling also
points out the danger in looking at the probability of such events.
He suggests that the catastrophic nature means that we should
prevent them if we possibly can and not apply economic cost benefit
analysis.
3. EMISSIONS
REDUCTION
3.1 It is important to realise that no reduction
in CO2 emissions can stop sea level rise. If all CO2 emissions
were stopped today we would still have a global warming problem
in 100 and even 500 years (Caldera et al Recent paper)
and Greenland would almost certainly be green. In fact most economists
and those in business and politics see it as obvious that emissions
will continue to rise for most of this century. The expected worldwide
economic development (plus 500% by 2050-Reith lecture 2007) just
can't be stopped.
3.2 Even if a large emissions reduction
could be achieved, the CO2 already in the atmosphere will last
more than a century and its net heating effect will persist. Temperatures
will therefore continue to rise. This could only be avoided if
the CO2 concentration could be reduced now to pre-industrial levels,
which is obviously impossible.
3.3 In addition large-scale removal of CO2
from the atmosphere cannot help quickly because the technology
simply doesn't exist yet.
3.4 If emissions continue to rise, as seems
inevitable, the escalating CO2 concentration will have to be controlled
by CO2 removal and storage (CRS). This massive volume technology
will have to be developed but this is not the subject of this
paper.
4. GEOENGINEERING
4.1 The only tools that we have available
to limit sea level rise come into the category of geoengineering.
There are several ideas that could be implemented quickly. Among
these is my suggestion of a stratospheric sunscreen created by
an aircraft fuel additive. (I now find that this was first suggested
by a Russian called Budyeko in 1980) but there are several others
including the well researched proposal for Ocean cloud enhancement
from Stephen Salter, Professor of Engineering at Edinburgh.
4.2 Almost all of these geoengineering ideas
aim at reflecting a proportion of the sunlight hitting the earth.
Several ideas, including my own, are specifically aimed at the
Arctic in order to stop sea level rise. Most rely on the "experiments"
already done by nature in the form of volcanic eruptions. There
have been 13 large volcanic eruptions in the last 250 years, which
have given us invaluable information on the global cooling that
can be achieved.
4.3 None of these ideas are yet sufficiently
well researched for immediate implementation but some of the ideas,
including my own, could be implemented within one or two years.
There are scientific voices claiming catastrophic consequences
of such implementation but it is difficult to envisage consequences
as catastrophic as allowing significant and unpredictable sea
level rise.
4.4 If the possibility of net loss from
Arctic and Antarctic ice sheets can be eliminated by local geoengineering,
then it should be possible to keep the total rise in sea level
to zero.
4.5 About half of the rise in the last decade
(about 3 centimetres total) is attributable to ocean expansion
on warming and the ocean cloud enhancement proposal from Professor
Salter could stop further warming of the sea water if researched,
developed and implemented.
5. POLITICS
5.1 Why aren't we hearing these suggestions
from the climate experts who should be putting them forward?
5.2 Any suggestion of geoengineering is
very political among climate academics. Roger Pielke, an academic
specialising in science policy summed up the situation very well
saying:
"some scientists think that scientists should
not discuss the prospects for geoengineering because it will distract
from other approaches to dealing with greenhouse gas emissions.
Thus, decisions about what research to conduct and what is appropriate
to discuss is shaped by the political preferences of scientists.
This won't be news to scholars of science in society, but it should
be troubling because it is unfortunately characteristic of the
climate science community (who)-try to tilt the political playing
field by altering what they allow their colleagues to work on
or discuss in public. The climate debate has too much of this
behavior already."
5.3 Anyone who looks at the debate quickly
comes to the same conclusion. Oliver Morton, news editor of Nature,
investigated geoengineering last year and wrote "-the climate
community views geoengineering with deep suspicion or outright
hostility". He also saw that "climate scientists have
shown new willingness to study (geoengineering) although many
will do so-to show that all such paths are dead-end streets."
5.4 Even the Nobel laureate (for his work
on CFCs and the ozone layer) Paul Crutzen couldn't get his geoengineering
paper published without the intervention of Ralph Cicerone, the
President of the American Academy of Sciences who wrote "many
in the climate academic community have opposed the publication
of Crutzen's work-for reasons that are not-scientific."
5.5 Against this background there will need
to be a strong political will to get proper, fully funded, research
and development for several geoengineering schemes. Then there
will need to be international political agreement on implementation.
6. GEOENGINEERING
RESEARCH PROJECTS
6.1 There is a tendency, particularly among
climate academics, to speak of geoengineering as a last resort
to be used "if disaster strikes". I have to describe
this as a completely unrealistic attitude to the problem that
is developing in Greenland and western Antarctica. The problem
is obvious and won't go away. We should therefore set about correcting
it now.
6.2 There are geoengineering schemes, like
mirrors in space, which might be interesting in the 22nd century,
but at this moment stratospheric aerosols must be top of the list.
From the 13 large volcanic eruptions since 1750, particularly
from Mount Pinatubo in 1991, we already have masses of experimental
data.
6.3 Most of the research and evaluation
papers concentrate on the quantities and the atmospheric and climatic
effects of stratospheric aerosols. There are various suggestions
for distribution but most of these are not detailed. If it could
be shown that aircraft fuel additives could distribute aerosols
without the need to develop any new equipment this would have
enormous advantages in allowing experimental distribution to be
done inexpensively and very soon.
6.4 An Actual Research Project
6.4.1 I have recently proposed the following
research project to Qinetiq (the former Royal Aircraft Establishment)
but there is at present no available funding.
6.4.2 Experiments using only static engine
test rigs would go a long way to proving the practicality of the
system at limited cost. The two chemicals suggested are di-methyl
sulphide to produce sulphur dioxide and tetra ethyl silicate to
produce silica. (I have already done some preliminary experiments.)
6.4.3 Most of the research on stratospheric
aerosols concentrates on sulphur dioxide which produces an aerosol
of sulphuric acid droplets. This is because it is sulphur dioxide
that is produced from a volcanic eruption and gives us most of
the data that we have on the cooling effects. There are various
disadvantages to sulphur dioxide in its chemical activity and
because of these it is worth investigating the silicon dioxide
(silica) alternative. It might have far less chemical effect on
the ozone. The particles might be crystalline platelets which
would float for much longer in the atmosphere. The particles might
be much more reflective requiring far less material to be injected.
It might be possible to choose particle size and therefore to
select the wavelength of light which is preferentially reflected.
(An extra ultraviolet sunscreen!)
6.4.4 If there is reason to believe that
the turbine will be affected by the use of tetra ethyl silicate
even in small concentrations then it would be nice to investigate
the possibilities of injecting the fuel/additive mixture into
an afterburner. It would be a pity to give up on the possibilities
of silica particles and it is likely that initial atmospheric
experiments would be done with military jets. Fighters using afterburners
are well-known for using up the maximum amount of fuel in the
minimum time and getting to the highest attitude.
6.5 Other Deserving Projects
6.5.1 With a developing emergency of the
global warming kind it is sensible to develop any feasible project
in parallel so that sensible choices can be made at a later stage.
One obvious candidate is the well researched proposal by Professor
Salter of Edinburgh University to spray sea water into the lower
clouds to enhance the reflectivity of ocean clouds and cool the
oceans.
6.5.2 This project would be least feasible
in the freezing conditions of the Arctic and is therefore particularly
compatible with the proposed use of stratospheric aerosols in
the Arctic and Antarctic.
7. IMPLEMENTATION
7.1 It does seem sensible to have an application
in mind in order to justify the preliminary experiments.
7.2 Even among those proposing stratospheric
aerosols there is scepticism as to whether aircraft fuel additives
could be a distribution system. The doubts expressed include:
(i) aeroplanes don't fly high enough in the stratosphere;
(ii) aerosols will fall out of the atmosphere
too quickly;
(iii) sulphur dioxide, which becomes sulphuric
acid, will damage the ozone layer;
(v) ozone layer damage will be particularly high
in winter (Recent Simone Tilmes paper);
(vi) aerosols will tend to cause high latitude
warming in winter because of reflection of outgoing radiation
during the longer nights relative to daytime; and
(vii) damage to the jet engine.
7.3 The most likely first application of
a stratospheric aerosol sunscreen is that proposed by Gregory
Benfold, a planetary atmospheric scientist at the University of
California. The title was "Saving the Arctic".
7.4 Combined with the aircraft distribution
system, the proposal would be to spread the aerosol by aircraft
flying between 40 and 60,000 feet from the time of first Arctic
daylight (April approximately) until late July approximately.
7.5 I believe that this would "slip"
neatly between the various disadvantages mentioned in the following
way:
7.5.1 Doubts 1 and 2. Ideally for very long
stratospheric life, aerosols need to be injected at about 80,000
feet. If they are only injected at 50,000 ft. they will fall out
of the atmosphere in about three months. (Ken Caldera's lecture
available on U tube). In this case that is exactly what we want
so that they would fall out by the end of the Arctic summer and
would not be present during the winter-solving 6. The aerosols
will probably also be more effective, weight for weight, in the
Arctic since there is no night during the summer when the night-time
blanketing effect has to be subtracted from the daytime screening.
7.5.2 Most of the arguments that aerosols
will damage the ozone layer assume that the aerosols are injected
high in the stratosphere for long life. In this case most of the
injection would not reach the ozone layer. In addition the aerosols
would no longer be present in winter when the effect is greatest.
(The damage to the ozone layer is not directly caused by the aerosols
but by the aerosol droplets or particles forming nuclei on which
the remaining CFCs have their chemical effect on the ozone. The
level of CFCs in the atmosphere is dropping steadily now that
controls are in place.)
7.5.3 The problem of acid rain, 4 above,
has always been a bit of a red herring because the quantity of
sulphur dioxide needed is only of the order of one per cent of
that produced by industrial processes worldwide. It could however
be eliminated if the silica particle version was used.
7.6 It seems very likely that implementation
of this type would succeed in "saving the Arctic". In
particular the target would be to eliminate significant melting
of the Greenland ice sheet or sudden loss of parts of it. The
same principle could then be applied to Antarctica.
7.7 The target should be zero sea level
rise. If this could be achieved the saving in costs of construction,
relocating populations and flood disasters would be absolutely
enormous.
References have not been included in this paper.
Most can be found in my poster/paper for the American Geophysical
Union 2007 at http://www.naturaljointmobility.info/agu.htm
September 2008
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