Engineering: turning ideas into reality - Innovation, Universities, Science and Skills Committee Contents


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) acid rain;

    (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





 
previous page contents next page

House of Commons home page Parliament home page House of Lords home page search page enquiries index

© Parliamentary copyright 2009
Prepared 27 March 2009