Climate change gets a lot of press these days. I’ve written about the topic as it relates to coral reefs on several occasions. With scientists using climate models to predict temperature increases — the Intergovernmental Panel on Climate Change (IPCC) stating that temperatures could increase substantially around the world over the next century — and the threat increased ocean temperatures pose to coral reefs through the process of coral bleaching, this is a topic that should be on every reef aquarist’s mind.
Let me state that I believe anthropogenic warming is real, there is good science to support it, and its effects can directly or indirectly harm coral reefs around the world.
That said, I believe climate modeling isn’t completely reliable at this point, and our understanding of the world’s climate systems is far from complete. We just don’t know what exactly causes changes to climate processes and systems, how those changes affect other systems and what our actions will ultimately have on the world’s climate.
I’m reminded of a speech Philip Seymour Hoffman’s character, a CIA operative named Gust Avrakotos, makes in the movie Charlie Wilson’s War. Gust tells the story of a Zen master who repeatedly responds to villagers’ assertions about the goodness or badness of particular events with the ambiguous statement “We’ll see.” Every time someone thinks something is either good or bad, the Zen master points out they really shouldn’t be so sure of what has happened, or what will happen.
To give you an idea of the uncertainty scientists have to consider, let me note that the IPCC’s 2007 AR4 Synthesis Report, the most recent publication from the IPCC, explicitly excludes information about the effect melting ice sheets will have on future climate model predictions.
Some researchers have criticized the IPCC over this because the ice sheet data would likely have a big effect on the IPCC projections. This and many other issues come to light in looking at the models the IPCC uses to make deductions about climate change.
While carbon dioxide is widely believed to be the main culprit behind global warming that has occurred in the last few decades, knowing this information doesn’t magically reveal the solution to the problem global warming poses. Even if we were able to stop injecting all carbon dioxide into the atmosphere, many scientists believe that additional warming is likely inevitable, regardless of future CO2 emissions.
And to stop producing carbon dioxide would likely prove ruinous to the world economy. In a time where we’re already facing unprecedented economic challenges, attempting to apply the brakes to world carbon output isn’t economically advisable, let alone feasible.
We have to keep in mind that the unintended consequences of our actions on a global scale seem to be what’s put us in this mess. We don’t even fully understand how our actions have affected global climate yet. Google “global dimming” to get an idea of how much we have to learn about how our actions can affect the climate.
Many processes and inputs affect the global climate, and slight changes in climate systems may have drastic effects on global climate. While the best science we have suggests that global warming is real, our best science can’t tell us what to do about it.
Iron-Built Ice Ages?
I bring this up because some scientists and others who influence public policy are calling for the application of radical geoengineering projects to counteract the rise in global temperatures.
Some pretty wild schemes have been proposed to reduce global warming. One plan called for adding huge amounts of iron to certain parts of the world’s oceans to stimulate phytoplankton growth. Phytoplankton use carbon in the process of building their shells, and the idea is to cause a phytoplankton population boom to sequester a large amount of carbon dioxide from the atmosphere.
Unfortunately (or fortunately, depending on your opinion of these geoengineering schemes), researchers attempting to demonstrate the feasibility of this method in the Southern Ocean found that the process didn’t work exactly as they hoped it would. While the predicted phytoplankton bloom did occur, it seems the carbon never made it to the deep ocean, where it would be stored over a long period of time.
This doesn’t mean the idea can’t work at all, but so far, using iron to seed the oceans and promote the growth of carbon-sequestering phytoplankton hasn’t proven to be the “silver bullet” some had hoped it would be.
With more study, scientists may figure out how this process can be harnessed. But that doesn’t mean it will prove to be a good thing. We just don’t know what effects iron-induced carbon sequestration might have on the environment or climate systems.
Other plans – some quite outlandish – have been proposed. One idea suggests we should put hundreds of thousands, or even millions, of large mirrors into orbit around the planet to redirect light away from the surface of the Earth.
This is a neat idea. It smacks of science fiction and – who knows? – it might do the trick, reflecting enough light away from the Earth to lower global temperatures.
But it’s pretty ambitious. Again, we don’t know what the side effects might be. Also, it would be enormously expensive. Just transporting the materials needed to put the mirrors into orbit would likely be prohibitively expensive, not to mention the actual construction issues and massive engineering challenges that would have to be addressed.
Another version of this scheme suggests we should add tiny reflective particles to our upper atmosphere, with much the same goal as the “mirror shield” proponents have in mind. Supposedly, the tiny particles will reflect enough light away from Earth’s surface to “control” global temperature increases.
The possible side effects of such a plan aren’t well understood. What happens if we overshoot and reflect too much light back into space? What if we inadvertently change rainfall patterns, cloud cover or something else? How many unforeseen issues might we unintentionally create through such foolhardy actions?
We just don’t know the answers to these questions. While we might be able to foresee some problems and compensate for unintended consequences, I believe we would inevitably make mistakes, possibly to our own detriment.
Corals Still in Decline
And in spite of our best efforts, new research suggests these geoengineering schemes aimed at preventing global warming won’t really help corals at all. A new study published in the journal Geophysical Research Letters titled “Sensitivity of ocean acidification to geoengineered climate stabilization” suggests that, even if global temperatures are stabilized or even reduced, ocean acidification will likely continue to be a threat.
I’ve written about ocean acidification in past blog entries. See “The Coral Reef Acid Test” for more information. This new report calls into question the use of geoengineering solutions to “fix” climate change, not because of what they will do, but because of what they won’t do.
Of course, scientists may come up with another geoengineering plan to save the reefs, but the same problems crop up. Also, the decline of the world’s coral reefs isn’t a foregone conclusion, though there is serious cause for concern. Read my blog entry “Reefs Show Signs of Rallying” for a discussion of the limitations of current knowledge in this area.
Hobbyists Can Help
We aren’t at the mercy of indomitable forces here. Hobbyists can do something about the problems facing the world’s coral reefs. We need new solutions to help support the world’s coral reefs.
And I believe hobbyists can help researchers and scientists find those solutions. Check out my blog “New Aquaculture Techniques,” where I mention some pretty interesting developments taking place in the world of aquaculture and how these developments might help coral reefs.
I don’t know what it will take to ensure the survival of coral reefs around the world or in reef aquariums. I don’t think there is a silver bullet we can use to solve all of our problems.
But, as I’ve said before, I do think reef aquarists are uniquely positioned to understand these issues and to make a positive impact.
What we started as a hobby may prove to be a great contributor to coral reef survival. Maybe the hobby can teach us something more profound than we thought.