Thursday, September 02, 2010

The control freaks are coming

kw: book reviews, nonfiction, climate change, geoengineering

Planethacking: (not plane-thacking but planet-hacking) noun; informal synonym for Geoengineering, a set of technologies for effecting global influence or control over climate and atmospheric dynamics.

Did you ever suddenly become aware of your breathing, and then try to control it? For a moment or two, it seems cool [in, out, huff, puff], but just as suddenly you realize with horror that to continue to breathe consciously becomes a kind of slavery. You dare not give attention to anything else!

The dilemma we face in a technological world is to decide what is worth controlling and what is better left to its own devices. HACK the Planet: Science's Best Hope—or Worst Nightmare—for Averting Climate Catastrophe, by Eli Kintisch, raises this question a half-dozen ways. Though the author bases his premises on greenhouse warming by CO2, clearly the big picture is that weather and temperature disasters are increasing, and this is going to lead to increased public desire, then pressure, to "do something about it."

In the author's view, we are quite likely to be pushed into doing something about it, and precipitously, all unprepared. Knowing that CO2 is much of the problem, there are two sides to dealing with it: making less of it or removing some of it. Making less involves conservation and developing more solar and renewable and nuclear energy sources (There is enough sunlight to run all of civilization, if we just have the political and financial will to install the infrastructure). Removing some of it, the author calls by the colorful term "the sucking 1-ton challenge": What is the minimum cost to remove a ton of CO2 from the atmosphere?

This is the first kind of geoengineering, because if it is done, it will be large in scale and global in scope. The atmosphere weighs 5.1×1015 metric tons (Tm). One part per million of this is 5.1×109Tm, or about five billion tons (that is 5.6 billion English short tons). The current CO2 concentration is 385ppm. To reduce this to 350ppm means removing 35ppm, or more than 175 billion tons of CO2. Problem one: What does each ton cost? Problem two: Where will you put it?

The author doesn't just discuss the various ideas for removing and "putting" the CO2, he discusses the people who are trying to work out the methods for doing so. These methods range from injection into the deep ocean or deep wells to making concrete, lots of it (build your next house from used CO2!). As to the latter idea, I got no sense of where we'd get that much calcium. Most of Earth's calcium is already carbonated; we call it limestone. Another scheme is to fertilize the oceans so plankton will bloom, removing CO2, at least for a while.

OK, that is one side. Many folks say we'll never be able to afford renovating the atmosphere directly, we should just do something to shield the planet from excess solar energy. This can be done by brightening clouds (force them to be made from smaller droplets) and by injecting sulfate aerosols into the stratosphere. My take on this is, let's not block the sunlight, let's instead use it to make solar energy so we're producing less CO2. All schemes for reflecting or blocking sunlight would make solar power less effective, a great loss. The only possible benefit of solar-blocking methods is that they cost a lot less than atmospheric revamping efforts.

Each chapter (there are twelve) is preceded by a short cautionary tale. Ranging from aerosol experiments in Russia a couple of years ago to introduction of various species (such as Nile perch) into new ecosystems to drying up the Aral Sea for Soviet agriculture, each resulted in disaster except the last, which utilized dung beetles in Australia to hasten the decomposition of cattle pats and reduce fly-borne diseases. That one, at least, worked well. Never mind that cattle are themselves an introduced species in Australia!

Clearly, while the author hopes something will work, he holds out little hope that it will. In a chapter on the politics of geoengineering experimentation, he found that the present social climate is very anti-experimentation. Nobody has yet been able to complete a large-scale experiment, so we haven't yet found out the most basic parameters.

Human emission of CO2 is actually a geoengineering experiment that has been going on for a century, and we are just now getting scientifically clear about its effects. It is not the first, however. Agriculture, which directly affects more than a quarter of Earth's land area, was the first geoengineering effort, with a duration of eight or ten millennia so far. Earth's biosphere has been remade to support about seven billion of us and our two billion cattle. Without this huge project, Earth could support no more than half a billion of us, or perhaps far less.

What would a further geoengineered world be like? According to David Brower, technology makes the world into a cage. The author closes with a riff on this: "Maybe geoengineering makes [the world] more like a terrarium, an enclosed, controlled garden. Even if geoengineering helps us one day stave off the worst climate crisis, we'll still be inside its walls."

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