It is generally agreed that global heating is dangerous and accelerating and that anthropogenic gas emissions are the primary cause. Still, we will surely burn more coal, oil, and natural gas in the coming decades than ever before, and, in the process, pump more greenhouse gases into the atmosphere and oceans. On that point there is consensus.[i] Globally, energy use is expected to increase at least three-fold by century’s end, and the atmospheric concentration of CO2 is expected to rise from its pre-industrial 280 parts per million[1] to 450, 550, or —given present trajectories— 1000 ppm.[ii] Climate models show that even the lower value may bring peril, but we have yet to veer an iota from the worst-case trajectory.[iii]
Given the ramifications to the biosphere, to the economy, and to humanity’s food security, we must change something.[iv] But what? Well, not our consumption, surely. Advertisers spend a half-trillion dollars annually to thwart that option, ever keeping our eyes screen-tunneled onto the prize.[v] Meanwhile, the material suffering of the billions of our human family around the world will be alleviated only by more consumption, of food, water, shelter, health services, and so on. Given civilization’s way of providing for these necessities, far more infrastructure, electricity, and energy will be required. The poorest billions have produced little of the nearly two-trillion tons of CO2 already released into the air since the industrial revolution.[vi] So, as global capitalism invites more of them to the party, their pollution will rise correspondingly.[vii] For nine billion people to enjoy First World prosperity with present technology will require daily consumption of over 800 million barrels of oil worth of energy—or ten times the oil we burn today.[viii]
And however integral they will be to future societies, alternative energy sources and energy efficiency will not solve our problems in the coming decades. Solar and wind have been the fastest growing energy industries worldwide, but we plan to burn more fossil fuel than ever before, as well.[ix] The human civilization train is heading directly for climate apocalypse, and there appears to be no simple off switch to kill the engine. Consciously or otherwise, we plan to consume more fossil fuel and release more CO2 and other greenhouse gases into the atmosphere, and we want to miraculously stop global heating.
Scientists are now seriously contemplating a most outrageous set of possible technological interventions—called geoengineering—that just a few years ago they had agreed to eschew out of fear of their potential repercussions.[x] Geoengineering involves large-scale manipulations of the atmosphere, oceans, and biosphere to offset global heating and to concoct felicitous climatic conditions.[xi] Geoengineering schemes include perhaps the most conjectural (too big to have been tested), potentially indispensable (the Earth might become uninhabitable, otherwise), and risky (because the first experiment will involve our entire planet) array of technologies yet conceived.
Whereas some decades ago science fiction writers and scientists were contemplating ways to terraform other solar bodies, such as the Moon and Mars, many of them have recently realized that, ironically, we may have to first terraform our own planet to keep it hospitable to us in the coming millennia. We might, for instance, capture the carbon emissions and pipe them underground, where they will hypothetically remain forever afterward. Maybe. And maybe we can suck out the carbon dioxide already in the atmosphere by placing huge contraptions across the continents and perhaps by growing forests of transgenic “carbon-eating trees.” Both of these are, so far, fantasy projects, beyond present technologies and without political support. For a less expensive alternative, maybe we can also manufacture massive plankton blooms in the oceans, inducing these microscopic organisms to remove the carbon for us. The ocean scenario imagines seeding stretches of the oceans with either iron or urea, which hypothetically will act as fertilizer, triggering a plankton population bomb… Bloom! (The same kind of bloom that sets off the coastal dead zones.) The micro-organisms would then sequester oceanic carbon (from CO2) into their bodies, and, upon death, fall to the sea bottom with this carbon, where it would be stored, again forever after. With lowered concentrations of carbon dioxide, the oceans would then sponge the gas faster from the air.
Or we could bypass the carbon cycle entirely. We can block the sun’s light before it reaches those pesky energy-absorbing greenhouse gases. We can release microscopic aerosols (salt, fine mist, or sulfur) into the atmosphere, or we can propel sunshades of various shapes, sizes, composition, and colors into space, placing them in orbit between Earth and sun. For aerosol delivery, we might use fleets of planes or ships, artillery batteries, or hoses suspended by zeppelins or balloons. To propel the trillions of needed sunshades, the proposed include spacecraft, cannon, and mile-long electromagnetic launchers with ion propulsion as a last booster stage.
The most popular of these schemes, hands down, is the pumping of sulfur particles into the air. It happens to be the cheapest, and it has been known to work, specifically with the 1991 eruption of Mount Pinatubo. Aerosol particles blown into the atmosphere by its eruption, mostly sulfur, lowered global temperatures by a degree Fahrenheit that year. And so enormous was Indonesia’s 1815 Mount Tambora’s eruption that its sulfate aerosols are credited for causing “the year without a summer” in 1816 throughout much of the northern hemisphere.[xii] The sulfate aerosols have the added advantage of being short-lived—they wash out of the atmosphere within a few years. So, there could be some precision in releasing our artificial volcanoes.
The blowback here is obvious to everyone. Besides the unknowns when dealing with a system as complex and dynamic as the Earth’s entire outer layer, there are the predictable possibilities of unintended climate anomalies, weakened India monsoons, and drought in the Sahel, all of which could be disastrous to hundreds of millions of people. “The year without a summer” saw the global temperature drop, climate anomalies, and widespread crop failures, famine, and disease outbreak. Aerosols also bring with them the very real potential for acid rain, ozone destruction in the stratosphere, and the associated destruction of life. And whereas the cost of sunshades (hundreds of trillions of dollars) will likely dissuade us from implementing that option, the ridiculously low cost of aerosol injection (tens of millions of dollars) could, perversely, prove to be its biggest disadvantage. A wealthy individual could, in a fit of megalomania, easily fund the endeavor. As could a rogue nation, acting with calculated self-interest. Politicians would be loath to enact costly policies that lower carbon emissions when such a cheap alternative was available. However, if emissions were not simultaneously lowered, the oceans would continue acidifying, as acidification is a result of CO2 chemistry, not sunlight. And finally, should blowback force us to discontinue the aerosol endeavor, global temperatures would quickly spike up to new highs that corresponded to the elevated CO2 levels, completely erasing the short-term benefits. And we would be that many more years behind schedule in doing the difficult work of lowering greenhouse gas emissions.
FOOTNOTES
[1] Carbon dioxide concentrations in the atmosphere are expressed in parts per million (ppm), which means the number of CO2 molecules per million total molecules of air.
ENDNOTES
[i] For example, Salameh (2003), Appenzeller (2006), Smil (2006b), EIA (2007), Kintisch (2007), Hightower and Pierce (2008).
Salameh, M.G. (2003) Can Renewable And Unconventional Energy Sources Bridge The Global Energy Gap In The 21st Century? Applied Energy, v. 75, pp. 33-42.
Appenzeller, T. (2006) The Coal Paradox: We Can’t Live Without it. But Can we Survive it? National Geographic, March, pp. 99-103.
EIA (U.S. Energy Information Agency) (2007) International Energy Outlook, Energy Information Administration, Dept. of Energy.
Smil, V. (2006b) 21st Century Energy: Some Sobering Thoughts, OECD Observer, No. 258/259, pp. 22-23.
Kintisch, E. (2007) Making Dirty Coal Plants Cleaner, Science, v. 317, pp. 184-186.
Hightower, M., and Pierce, S.A. (2008) The Energy Challenge, Nature, v. 452, pp. 285-286.
[ii] Hoffert et al. (2002), Potocnick (2008), Monastersky (2009), Schneider (2010).
Hoffert, M., Caldeira, K., Benford, G., Criswell, D.R., Green, C., Herzog, H. et al (2002) Advanced Technology Paths to Global Climate Stability: Energy for a Greenhouse Planet, Science, v. 298, pp. 981-987.
Potocnik, J. (2008) Renewable Energy Sources and the Realities of Setting an Energy Agenda, pp. 16-20, in D. Kennedy (Editor), Science Magazine’s State of the Planet 2008-2009, AAAS, Island Press, Washington.
Monastersky, R. (2009) Climate Crunch: A Burden Beyond Bearing, Nature, v. 458, pp. 1091-1094.
Schneider, S. (2010) The Worst-Case Scenario, Nature, v. 458, pp. 1104-1105.
[iii] Hansen et al. (2008), Potoknick (2008), Meinshausen et al. (2009), Monastersky (2009), Schneider (2010).
Hansen, J., Sato, M., Kharecha, P., Beerling, D., Berner, R., Masson-Delmotte, V., Pagani, M., Raymo, M., Royer, D.L., and Zachos, J.C. (2008) Target atmospheric CO2: where should humanity aim? Open Atmospheric Science Journal, v. 2, pp. 217-231.
Meinshausen, M., Meinshausen, N., Hare, W., Raper, S.C.B., Frieler, K., Knutti, R., Frame, D.J., and Allen, J.R. (2009) Greenhouse-gas emission targets for limiting global warming to 2°C, Nature, v. 458, pp. 1158-1162.
Monastersky, R. (2009) Climate Crunch: A Burden Beyond Bearing, Nature, v. 458, pp. 1091-1094.
Schneider, S. (2010) The Worst-Case Scenario, Nature, v. 458, pp. 1104-1105.
[iv] See Chapters 2 and 7 of Schneider, S. (2010) The Worst-Case Scenario, Nature, v. 458, pp. 1104-1105.
[v] New York Times Almanac (2008:) estimates U.S. advertising budgets at over $270 billion a year, and this includes only ad placement, not production costs. U.S. advertising budget is about half of the world total budget.
[vi] Smil (2000a), Allen et al. (2009).
Smil, V. (2000a) Energy in the Twentieth Century: Resources, Conversions, Costs, Uses, and Consequences, Annual Review of Energy Environment, v. 25, p. 21-51.
Allen, M.R., Frame, D.J. Huntingford, C., Jones, C.D., Lowe, J.A., Meinshausen, M. and Meinshausen, N. (2009) Warming Caused by Cumulative Carbon Emissions Towards the Trillionth Tonne. Nature, v. 458, pp. 1163-1166.
[vii] Purushothaman (2003), Flavin and Gardner (2006), Walsh (2006), Sawin and Mukherjee (2007), Takashi (2007).
Purushothaman, R. (2003) Dreaming with BRICS: The Path to 2050, Goldman Sachs Global Economics Paper No: 99. http://www2.goldmansachs.com/insight/research/ reports/99.pdf .
Flavin, C. and Gardner, G. (2006) China, India and the New World Order, pp. 3-23 in The World Watch Institute, State of the World, 2006 (L. Starke, ed.), W.W. Norton and Co., New York.
Walsh, B. (2006) The Impact of Asia’s Giants: How China and India Could Save the Planet—or Destroy it, Time, April 3, p. 61-62.
Takashi, S. (2007) What the Economic Rise of China, India means for Japan, CEAS (Council on East Asian Community) June 19. Available at http://www.ceac.jp/e/commentary/backnumber.html
[viii] Extrapolating from Smalley, R.E. (2005) Future Global Energy Prosperity: The Terawatt Challenge, Materials Research Society Bulletin, v. 30, pp. 412-417.
[ix] Parfit (2005), Kammen (2006), Sawin (2007:36-39), Sawin and Mukherjee (2007).
Parfit, M. (2005, August) Future Power, National Geographic, pp. 4-31.
Kammen, D.M. (2006) The Rise of Renewable Energy, Scientific American, v. 295, pp. 84-93.
Sawin, J.L. (2007) Wind Power Still Soaring, pp. 36-37, and Solar Power Shining Bright, pp. 38-39, in The World Watch Institute: Vital Signs 2007-2008, W.W. Norton and Co., New York.
Sawin, J.L., and Mukherjee, I. (2007) Fossil Fuel Use Up Again, pp. 32-33 in The World Watch Institute: Vital Signs 2007-2008, W.W. Norton and Co., New York.
[x] Tollefson, J. (2010) Geoengineers Get the Fear, Nature, v. 461, p. 656.
[xi] Sources for geoengineering and its blowback from Hoffert et al. (2002), Angel (2006), Broad (2006), Morton (2007), Young (2007), Caldeira (2008), Biello (2009), Boyd et al. (2009), Jones (2009), Morton (2009), Shepherd (2009), Wood (2009), Keith et al. (2010), Kintisch (2010), Robock et al. (2010), Schneider (2010), Tollefson (2010), Pearce (2019, May 29).
Hoffert, M., Caldeira, K., Benford, G., Criswell, D.R., Green, C., Herzog, H. et al (2002) Advanced Technology Paths to Global Climate Stability: Energy for a Greenhouse Planet, Science, v. 298, pp. 981-987.
Angel, R. (2006) Feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1), Proceedings of the National Academy of Sciences of the United States of America (PNAS), v. 103(46), pp. 17184-17189.
Broad, W.J. (2006, June 27) How to Cool a Planet (Maybe), New York Times.
Morton, O. (2007) Is This What It Takes To Save The World? Nature, v. 447, pp. 132-136.
Young, E. (2007, September 15) A Drop in the Ocean, NewScientist, pp. 43-45.
Caldeira, K. (2008) Taming the Angry Beast, Science, v. 322, p. 376-377.
Biello, D. (2009, June) Can Captured Carbon Save Coal? Scientific American, Earth 3.0, pp. 52-59.
Boyd, P.W., Jickells, T., Law, C.S., Blain, S., Boyle, E.A., Buessler, K.O., Coale, K.H., Cullen, J.J., and fifteen other authors (2009) Mesoscale Iron Enrichment Experiments 1993-2005: Synthesis and Future Directions, Science, v. 315, p. 612-617.
Jones, N. (2009) Sucking it up, Nature, v. 458, pp. 1094-1097.
Morton, O. (2009) Great White Hope, Nature, v. 458, pp. 1097-1100.
Shepherd, J.G., Working Group on Geoengineering the Climate (2009) Geoengineering the climate: science, governance and uncertainty (RS Policy document, 10/29) London, GB. Royal Society 98pp.
Wood, G. (2009, July/August) Moving Heaven and Earth, The Atlantic, pp. 70-76.
Schneider, S. (2010) The Worst-Case Scenario, Nature, v. 458, pp. 1104-1105.
Keith, D.W., Parson, E. and Morgan, M.G. (2010) Research on global sun block needed now, Nature, v. 463, pp. 426-427.
Kintisch, E. (2010) ‘Asilomar 2’ Takes Small Steps Toward Rules for Geoengineering, Science, v. 328, pp. 22-23.
Robock, A., Bunzi, M., Kravitz, B., Stenchikov, G.L. (2010) A Test for Geoengineering? Science, v. 327, pp. 530-531.
Tollefson, J. (2010) Geoengineers Get the Fear, Nature, v. 461, p. 656.
Pearce, F. (2019, May 29) Geoengineer the Planet? More Scientists Now Say It Must Be an Option. Yale Environment 360, Yale School of Forestry and Environmental Studies.
[xii] Oppenheimer, C. (2003) Climatic, environmental and human consequences of the largest known historic eruption: Tambora volcano (Indonesia) 1815, Progess in Physical Geography, v. 27, pp. 230-259.