While governments tinker at the margins of miserably inadequate ETS schemes, a survey of 80 international climate scientists by The Independent reveals 54% consider recent climate developments so dire that attempts at geo-engineered mitigation, or “Plan B”, are unavoidable.
About 35% of respondents disagreed with the need for a “Plan B”, arguing that it would distract from the main objective of cutting CO2 emissions, with the remaining 11 per cent saying that they did not know whether a geo-engineering strategy is needed or not.
Attempts at geo-engineering, aimed at artificially reducing solar radiation, as originally suggested by Paul Crutzen, the Nobel Prize atmospheric physicist, include artificially increased albedo (reflection) of the stratosphere, probably over the Arctic circle where ice melt and albedo loss are fastest. This could be achieved by injection sulphur dioxide aerosols, possibly shot from guns or mixed in jet fuel of planes over-flying polar regions.
The effects would be similar to volcanic events, such as the 1991 Mount Pinatubo eruption, or the 1816 Mount Tambora eruption, which resulted in freezing winters and snow storms in Europe and North America (dubbed “the year without a summer”). Both eruptions resulted in cooling of the Earth surface by about 0.5 degrees C for a couple of years.
Injection of sulphur dioxide into the stratosphere are converted to sulfuric acid aerosol dust veil that encircles the Earth. Estimates of the mass of SO4 for the Tambora eruption vary between 60 and 100 terragram (0.6 to 1.0 million ton), not an easy task for a geo-engineering effort.
Other means of increasing the Earth albedo include dissemination of aluminum particles in or above the stratosphere, or installation of large solar reflectors in space. A “sunshade” 1800 km in diameter was proposed by Roger Angel to NASA, consisting of 16 trillion discs, contained in capsules fired by electric or magnetic guns (railgun, coilgun) to positions 1.5 million km from the Earth and capable of blocking 2% of sunlight, i.e. regulating several Watt/m2 of solar energy.
Other proposed methods include ocean fertilization with iron filings, enhancing algal and phytoplankton growth and photosynthetic CO2 capture, cloud seeding by atomized sea water (John Latham, US National Centre for Atmospheric Research; Stephen Salter, Edinburgh University; Mike Smith at Leeds), sodium pipe systems (“trees”) sequestering CO2 to sodium carbonate, and other methods, and vertical ocean-wide pipe systems to help pump cold CO2-absorbing water to the surface.
All these methods risk yet unforeseeable complications and side effects, including “collateral damage”.
That an interest grows in atmospheric geo-engineering, including US conferences, underpins the bankruptcy of international attempts at emission cuts. This includes partly watered down IPCC reports and woefully limited emission reduction targets of Kyoto — not to mention failures in Bali and Poznan, Garnaut’ conservative emission cut recommendations, and the 5/15 whitewash paper.
The astronomical costs of proposed geo-engineering methods make mockery of the economy-based arguments raised by business and governments against deep reduction in carbon emissions (while trillions are used for military purposes and the rescue of bankrupt financial institutions). The time for “business as usual” is nearly over.
Dear Jackie,
The difference is that the Pleistocene ice ages were caused by natural orbital (solar) forcing, not by humans.
Homo “sapiens” (so called) has now developed the means of warming the planet, which means that – in principle – had an ice ages threatened civilization, the species could delay such developments through carbon emissions.
Cooling is much more difficult and uncertain and geo-engineered albedo enhancement would be short lived, only a few years, offering no more than a band aid.
If it is necessary to resort to such geo-engineering solutions then I for one believe that we would be far better off giving up and enjoying what time we have left. All such solutions will bringunknowabnle unknown reactions from the ecology of the planet that will create even more and bigger problems. Becasue I do not beleive the situation is that dire, although dire enough, I would prefer to see much stonger attempts atr population control, a phase out of coal power statio within 15 years, investment in green housing for all starting with the homeless and a cesssation of the war in Iraq to save the money needed to take the necessary action.
Re Cooling the planet…but what if they get it, er, slightly wrong?Look at the last 100,000 years, not the last 100 years. Ice has threatened humanity a lot more than heat.
As for geo engineering, methinks unintentionally we’ve been seeing that with the soot out of fairly dirty hyper economic expansion from China and India for a good few years now, which to me correlates neatly with the AGW plateau the sceptics get in a lather about.
But the rate of such pollution just cut down with the GFC intervention recently. Methinks they just lowered the umbrella folks. Which means the exponential rate of change from a deceptively low base will probably crank up faster now.
geo-engineering to artificially reduce solar radiation – unproven technology at astronomical cost.
let’s apply ockam’s razor – the simplest solution is the right one – and put just 1% of the money some geo-engineering project would require into supporting graziers to change their management practices.
Tim Flannery has identified revegetating our planet’s desertifying grazing lands as one of our best means for addressing climate change – let alone its benefits for drought and flood mitigation, boosting biodiversity and genuinely commencing the healing of our inland river systems.
The more complex the problem, the simpler the solution will be. See http://www.soilcarbon.com.au for more.