In his quirky but groundbreaking book, Operating Manual for Spaceship Earth, Buckminster Fuller pointed out that if you are aboard a sinking ship, even a floating piano top can look extremely promising. But Fuller also notes that this doesn’t mean a piano top is the ideal design for a flotation device.
To continue the metaphor, in the absence of anything like a global plan to combat the planetary climate crisis, we seem to be searching the horizon for piano tops, forcing ourselves into a series of more and more uncomfortable decisions regarding energy, resources and the ecology that supports us. In almost every sphere of the environmental movement, you see strategies once considered beyond the pale under serious consideration–only because the options grow worse and worse each day. Should we allow hydro-fracturing for shale gas if it keeps us from using the even more damaging Canadian tar sands? If we could eliminate mountaintop removal to extract coal by ramping up our nuclear power output shouldn’t we consider doing that? Even if tomorrow there were some miraculous global compact to transition to 100% renewable energy, these questions would need to be resolved to determine how we bridge to that desired outcome.
A recent addition to this growing list of uncomfortable strategies under consideration is geoengineering: the science of intentionally altering the earth’s atmosphere to curb the rise in average global temperature. As we continue to burn fossil fuels at a breakneck pace and as negative feedback loops in the global system (like the growing seasonal reductions in the polar ice cap or the release of methane from melting permafrost grow worse much more quickly than expected, a growing chorus advocates for a dramatic response: injecting sulfate particles into the atmosphere that will reflect significant amounts of the sun’s heat, thereby slowing the rise in global temperature. What might once have sounded liked science fiction is being studied and discussed by reasonable, intelligent people with no particular ax to grind.
A few weeks back Michael Specter at the New Yorker did a wonderful job of summing up the recent scientific activity in the field, and there have been other discussions of the subject at Scientific American and Wired. Yale 360 surveyed the pros and cons here.
The basic idea is to mimic a major volcanic eruption, without the big bang and the earthquakes. When Mount Pinatubo erupted in 1991, huge quantities of sulfur dioxide were released into the atmosphere and a period of global cooling followed. Scientists surmise that a continued infusion of sulfates would result in long-term cooling of global average temperature. Tinkering with the earth’s atmosphere is not for the faint of heart. Somehow filling the atmosphere with sulfates would need to happen every year, in perpetuity, or the cooling effects would cease. Perhaps more importantly, many are concerned that even discussing the concept of geoengineering will give those that are already complacent about climate change an excuse to ignore the subject entirely under the assumption that a simple technical fix will be found. Others have pointed out that simply reflecting the sun’s heat while continuing to pump CO2 into the atmosphere will do nothing to curb acidification of our oceans, one of the most dreadful and largely ignored impacts of the current climate crisis.
Ultimately, what should give us pause about geoengineering are the things we don’t know. The atmosphere is too complex a system to think that we can start mucking with it and have anything like a comprehensive sense of the repercussions. For instance, many fear that geoengineering has the potential to seriously disrupt the Indian monsoon. The list of things we don’t know about how the atmosphere interacts with our planetary ecology is almost unfathomably long. I was reminded of this when someone recently described to me the relatively recent discovery of ballooning spiders, which cast their gossamer into the air like a sail and are carried off by the wind to new domains. These spiders have been found upwards of 16,000 feet above sea level and travel many hundreds of miles. Will geoengineering impact this species? I doubt anyone really knows. And how many others are there like them? Or consider the emerging understanding about how microbes in our stratosphere impact rainfall, disease and climate? How will geoengineering affect this almost unknown ecology?
Humans have a tendency to assume that what we know is all there is to know, or close to it. Ultimately, the thing that should make us wary of geoengineering is the same thing that should lead us to slow our emission of greenhouse gases, because we don’t really know how it will impact our otherwise stable global climate.