In yesterday’s Crikey Clive Hamilton described the rather curious, possibly sinister, action by the Victorian government to investigate geoengineering. The two main risks with the kind of geoengineering being considered are the acidification of rain/oceans and the moral hazards of political inaction on decarbonising our energy sources.

However, if one believes that renewable energy is inevitable but may yet take another 25 years or more to be economic, and even longer to displace established energy infrastructure, then I don’t see that anyone could really object to drastic measures to prevent the kind of worldwide calamities Hamilton describes in his book Requiem for a Species.  It could buy sufficient delay to allow the atmosphere and oceans to equilibrate to the new stable carbon cycle that the earth ultimately needs.

On the other hand, proper research is required and most likely can only come from government-funded projects rather than leaving it to the get-rich quick private sector (as in those inconclusive and unregulated ocean seeding experiments).  Because it involves huge ecosystems, potentially the whole planet, it will take decades. There are probably compounds other than sulphur dioxide that can avoid the acidification.  Geographic localisation may be possible/effective, for example to prevent the Arctic completely melting and potentially disrupting the Gulf Stream (which could turn Europe into West-Siberia), the equivalent of putting a transient umbrella over the poles.

Yes, ecologists everywhere have shivers of apprehension running down their spines but that is why it will take decades.  It would involve beginning with very low dose experiments and observing the results. The reality is that this type of experiment has already been done inadvertently due to the sulphur content in aviation fuels that have been deposited in the upper atmosphere in ever-increasing amounts over the past few decades.  The massive shutdown of airspace following 9/11, and recently during the eruption of that volcano in Iceland, have shown that we have already moderated global warming by this means.  The atmosphere heated up measurably while the planes were grounded.

As Hamilton has described elsewhere, climate scientists believe the world is going to exceed atmospheric levels of carbon dioxide that imply irreversible consequences over the coming century. Warming is only one effect so geoengineering can only be a stop-gap to prevent the worst of shorter-term effects. To counter the full effects the carbon has to be removed, and ideally, or necessarily, not by being absorbed by the oceans.

Bio-sequestration has enormous potential in the form of iron seeding of oceans and charcoal in soils.  But again a lot of research is required as no one really understands the processes or long-term effects.  There is some optimism for ocean seeding because it is potentially easy, cheap and scalable — and innocuous.  There are vast segments of the Pacific ocean that are dead zones with very little life — because they are a long way from coasts and do not have currents to bring nutrients, one of which, iron is limiting to the growth of blue-green algae and phytoplankton, the very bottom of the whole ocean food chain. (But don’t fret, the amount of iron required will not add much to Clive or Twiggy’s billions, though here’s a thought: maybe they might like to fund the research?)

This is kind of equivalent to carbon capture and storage (CCS) except it is done naturally by organisms and the carbon is sequestered as stable calcium carbonate skeletons that fall to the ocean floor at the end of the animals’ life.  In fact it is a kind of solar power as the energy that drives the process is free from the sun coupled to a billion years of biological evolution.  It is why it is economically feasible and clean coal is not.) This process is the origin of the massive limestone deposits throughout the world, such as those exposed in the White Cliffs of Dover. Staggering amounts of carbon are embedded in these deposits and in principle, creating some more in some unoccupied part of the Pacific may well be ecologically innocuous and very affordable.

Feasibly these geo- and bio-sequestration possibilities might remove motivation to develop renewable energy but I doubt it would be more than a delay.  Paying more and more for oil, gas or coal (and its impossibly expensive cleaning) will drive development of solar, wind, geothermal and other massive reserves of energies (tidal, ocean wave) that are waiting for our ingenuity in extracting it at competitive cost.

Finally, whatever may be done in terms of global engineering or sequestration efforts, it will need to be funded. We all share the same atmosphere and oceans so we all must pay, logically in proportion to the amount of carbon we put into the atmosphere.  The only realistic means is via a carbon tax applied globally.

Dr Michael R. James is an Australian research scientist and writer.