When Mount Pinatubo in the Philippines erupted in June of 1991 – the second largest eruption of the twentieth century – all the expected things happened: pyroclastic flows, ash deposits, mass evacuations of nearby villages and lahars, or mudflows resulting from rain mixed with ash and sand. Following the eruption, something curious happened, however: average temperatures all over the world dropped one-half degree centigrade for two years. After the eruption of Mount Tambora in Indonesia in 1815, notable cooling of the planet was observed for nearly three years. The New England states experienced what came to be known as “The Year Without a Summer” as the region saw widespread snow and frosts during the months of June, July and August of 1816, leading to ice in shipping channels during the summer, crop failures and widespread hunger.
Scientists have long known that strong volcanic eruptions lower global temperatures, sometimes for years. It’s not a mystery as to why: when you fill the atmosphere with particulate material, it helps block some sunlight from reaching earth, leading to a cooling of the planet. Since we appear to have a planet that’s getting progressively warmer on our hands right now, many researchers have begun to wonder: can we manufacture “artificial volcanoes” to try and artificially lower global temperatures to stave off the worst effects from the buildup of greenhouse gasses?
Scientists in the UK appear to be about to try, though there’s no actual volcanoes involved, so if you’re the sort of person who likes to watch stuff explode, don’t get too excited.
Instead, researchers will attempt to pump water up a hose suspended one kilometer off the ground underneath a dirigible, according to British newspaper the Telegraph.
While it’s a bit peculiar and a long way from an actual artificial volcano, the researchers behind the project say it could be the first step in a giant Earth-wide “geoengineering” project that will take decades but might, in the end, help cool the planet. If the initial first phase of the project, scheduled to kick off in October, works, researchers envision using football-stadium-sized blimps, each with 20 kilometer-long hoses to pump light-scattering particles (non-toxic, unlike the material that volcanoes spew out) high into the Earth’s stratosphere. The particles will theoretically remain in the atmosphere, reducing the amount of solar radiation that reaches the Earth, ultimately cooling off the planet.
The project, called SPICE (Stratospheric Particle Injection for Climate Engineering) is coming out of the University of Bristol in
England. The team is led by Dr. Matt Watson, who told the Telegraph, “This is a controversial and potentially alarming subject. We’re going to try to pump tap water to a height of one kilometer through a pipe as a test of the technology.”
Phase one testing will take place on a disused airfield at Sculthorpe in north Norfolk using something similar to the Goodyear blimp. The water will be forced up the pipe using an ordinary pressure pump. After the water is forced up the pipe, it will ultimately fall as artificial rain.
The project has been initiated to answer a number of questions researchers have about the practicality and feasibility of future geoengineering (defined by the British Royal Society as the deliberate large-scale manipulation of the planetary environment to counteract anthropogenic climate change) projects. For starters, scientists need to determine what the ideal particle would be to send up into the stratosphere. It would need to be something with excellent solar radiation scattering properties, but at the same time safe for human health. Researchers will also need to evaluate the effects of wind acting on a blimp tethered one kilometer off the ground with water being pumped into it at a rate of around one kilogram (2.2 pounds) per minute.
If the project goes as planned, say researchers, they think that ultimately by sending tons of material into the stratosphere from future “artificial volcanoes,” they can put enough reflective material around the Earth to drop the planet’s average temperature by about two degrees Celsius, which doesn’t sound like much, but it could be enough to offset some of the worst weather effects that could be caused by the warming of the planet.
It certainly won’t be easy. Researchers say that even if they are successful, to recreate the project on a large scale would require a lot of resources plus the cooperation of governments around the world to coordinate efforts. In addition, the researchers warn that the potential side effects and risks of such a venture would need to be fully evaluated and weighed. For instance, would it affect local weather negatively, putting crops in danger? Would it be seen by the public as an instant fix, thereby causing people to abandon power conservation and clean energy efforts? Would it harm the ozone layer? Would it change the chemistry of the Earth’s atmosphere, causing unintentional problems down the road?
“We are still decades away from doing this and it’s not simply a science decision,” said Watson. “There are ethical and governmental decisions around this that are huge. Just because we can do it doesn’t mean that we have the right to do it.”
Which brings up some overall problems that will be faced by any future geoengineering processes. First of all: the public isn’t that thrilled about the idea. (Whether the public is generally capable of assessing and understanding, in context, all the ramifications of the projects is a story for another day.) A study conducted earlier this year by Cardiff University found that while most people questioned about the process agreed that research ought to go ahead, “very few were fully comfortable with the notion of stratospheric aerosols as a response to climate change.”
Back in 2009, Britain’s Royal Society published a paper evaluating all the possible methods of geoengineering to help clean up and cool the earth. Some of the methods suggested, which included fertilizing the oceans to encourage algae blooms that would suck up carbon dioxide, were determined to be technically possible, but costly and risky from the standpoint of making unintentional changes to the Earth’s ecosystems that could have far-reaching effects.
Proposed geoengineering projects – which are often called “Plan B projects” since they represent secondary activity after the first option of reducing the amount of carbon that is put into the atmosphere in the first place – fall into two categories, says the Royal Society. The first falls under the umbrella of carbon dioxide removal (CDR) techniques, which literally scrub carbon dioxide from the atmosphere. While the premise is straightforward and no one doubts the efficacy of the methods, it has been determined to be slow and expensive. The second category is “solar radiation management,” the category under which the artificial volcano concept falls. It would be quicker, say scientists, reducing temperatures in a short period to address the kind of climate “catastrophe” that some scientists say is rapidly heading our way; however, it would have more unintentional side effects and still doesn’t address the root of the problem, which is too much CO2 and other greenhouse gasses being put into the Earth’s atmosphere.
Still, the “artificial volcano” scenario was found by the Royal Society to be the most feasible and affordable of the geoengineering options studied (though the carbon dioxide removal method is generally believed to be the more effective in the long-run).
Other ideas being discussed in terms of geoengineering include the interesting, the far-fetched and the “slap your forehead” kind of ideas:
Scrubbing the atmosphere: This would involve deploying atmospheric “scrubbers” all over the world that that actively process air and draw CO2 it.
Rocks that suck up carbon dioxide: Scientists have proposed mining rocks that naturally react with carbon dioxide to form solids (rocks that contain high levels of silicates and carbonates), which could be then spread in soil.
Giant space mirrors: Some researchers have proposed putting huge mirrors into orbit around the earth in an effort to reflect more sunlight and keep it from reaching the Earth. This doesn’t seem such a great idea when you think about how long it has taken to get a single space telescope, the James Webb Space Telescope into readiness for launch, and how far over-budget the project has gone.
Paint the world white: While the builders of green homes and commercial buildings understand that installing white, instead of black, roofs on buildings helps keep the building cooler, some have called for a project that would essentially paint every roof in the world white and while at the same time using lighter-colored materials for road-building as a way of reflecting more solar radiation back into space. Fans of this program include Steven Chu, the U.S. Energy Secretary. Critics call it expensive, impractical and of very little value, since there just aren’t enough roofs and roads in the world to make enough of a difference.
Polar ice cap enhancement: While the rate and causes of the melting of the polar ice caps remains a contentious issue (to say the least), geologists do agree that the polar ice caps play a very important part in the Earth’s climate, and that their shrinkage or disappearance could threaten life on Earth. Some researchers have proposed spraying fresh lake water (since it freezes faster than salt water) over areas of the polar ice caps to thicken them in a sort of “cryospheric” geoengineering process and to insulate the salt water ice beneath.
Phytoplankton blooms: When phytoplankton grows in large “blooms” offshore, it “locks up” carbon dioxide. Some scientists have proposed encouraging giant phytoplankton blooms by fertilizing existing blooms with iron oxide, which could help reduce carbon levels. There would be a high risk with this method, however, of causing unintended changes to the oceans’ eco-systems.
Ocean water mixing: Since the Earth’s oceans are warming, a scenario that could lead to more intense, destructive hurricanes, some have suggested using giant vertical ocean pipes that would bring cooler water up from bottom of the ocean to mix with warmer surface water, resulting in a net lowering of water temperature. The strategy has been proposed (by Bill Gates oddly enough, along with others) as less of a way to cool the earth and more as way to mitigate or deflect damaging hurricanes. Gates and others actually filed a patent application (US Patent Application No. 20090177569 ) for the proposed methodologies two years ago.
Not everybody’s a fan, however. The whole geoengineering concept makes many environmental groups uneasy, though they may laud the goals of the projects.
“Intervening in our planet’s systems carries huge risks, with winners and losers,” Greenpeace’s chief scientist, Doug Parr, told Bloomberg. “If we can’t deliver political action on clean energy and efficiency then consensus on geo-engineering is a fantasy.”
Others criticize the processes for being bandages slapped on over festering wounds without treating the wounds themselves.
“Putting sulfur particles into the atmosphere is cheaper than reducing greenhouse gas emissions, but it doesn’t solve the problem,” said Ken Caldeira a professor and climate modeler at the Carnegie Institution’s Stanford, California-based ecology department. “It’s more like a painkiller, masking symptoms of the disease.”
Geoengineering methods will also be a hard sell to world governments, who would be required to lay out of a lot of the cash for many of these projects. John Shepherd, a professor of Earth Systems Science at Southampton University in the UK believes that each world government should currently be investing about 100 million pounds (about $158 million) a year to research these techniques.
Which would be a bit like trying to sell ice cubes in Greenland in most national capitals right about now.