Tag Archives: Ken Caldeira

Would geoengineering really have NO impact on ocean acidification?

Image courtesy of Flickr user Jenny Lee Silver, used under Creative Commons

It’s often repeated uncritically that aerosol geoengineering will “do nothing” to prevent ocean acidification, but the reality is more complex.

We know from past volcanic eruptions that the diffuse light created by stratospheric aerosol injections can potentially promote productivity in the terrestrial biosphere, although there is significant regional heterogeneity (Gu et al., 2003; Mann et al., 2012). This is the first indication that there is more going on than just a simplified, decoupled ocean and atmosphere response. Clearly we need to look at the interaction of the carbon cycle between all reservoirs, including the terrestrial sink.

When we do this using relatively simple (Earth system) models, we find that indeed the response from the terrestrial biosphere is very important in looking at the effects of aerosol geoengineering on ocean acidification (Matthews et al., 2009). What we see is that the lower temperature and increased carbon uptake by the terrestrial biosphere actually slows pH decrease a little relative to a non-geoengineering scenario (but has no change on aragonite saturation levels). Other experiments suggest that this increase in terrestrial carbon uptake might occur due to decreased higher latitude heterotrophic respiration and increased tropical productivity (Tjiputra and Otterå, 2011). These experiments indicate that while the cooler ocean waters are more soluble to atmospheric CO2, this is largely offset by a reduction in the ocean-atmosphere CO2 partial pressure gradient. It should be noted that these OA reductions are small relative to an unchecked emissions-driven scenario.

Thus, aerosol geoengineering may actually slightly reduce the rate of ocean acidificaiton due to increased terrestrial carbon uptake, but more study is needed. Even with geoengineering, however, ocean acidification is a serious threat to ocean life.


  • Gu, L., D. D. Baldocchi, S. C. Wofsy, J. W. Munger, J. J. Michalsky, S. P. Urbanski, and T. A. Boden (2003), Response of a Deciduous Forest to the Mount Pinatubo Eruption: Enhanced Photosynthesis, Science, 299(5615), 2035–2038, doi:10.1126/science.1078366.
  • Mann, M. E., J. D. Fuentes, and S. Rutherford (2012), Underestimation of volcanic cooling in tree-ring-based reconstructions of hemispheric temperatures, Nature Geoscience, 5(3), 202–205, doi:10.1038/ngeo1394.
  • Matthews, H. D., L. Cao, and K. Caldeira (2009), Sensitivity of ocean acidification to geoengineered climate stabilization, Geophys. Res. Lett., 36, 5 PP., doi:200910.1029/2009GL037488.
  • Tjiputra, J. F., and O. H. Otterå (2011), Role of volcanic forcing on future global carbon cycle, Earth System Dynamics, 2(1), 53–67, doi:10.5194/esd-2-53-2011.

The Freakonomics solution to finding yourself in a hole

Or: Levitt and Dubner Keep Digging, Part One

You’d think that the authors of a pop-econ best seller would be familiar with the sunk cost effect. You’d be wrong.

Criticism of Levitt and Dubner’s (L&D from here on) atrocious chapter on climate has been swift and remarkably in-depth. L&D have been shown to have misrepresented everything from the position of their main expert Ken Caldeira to alleged global warming caused by solar panels.

Rather than acknowledge that they’ve massively screwed up,  L&D have gone on the attack- they’re trying to dismiss the substantive and largely unanswered critiques of their shoddy work as little more than the response of religious zealots, and refocus media attention to their ‘unconventional, counter-intuitive, boy aren’t we more clever than the conventional wisdom’ trademark insights.

L&D want you to know that this whole climate change problem could be solved at a mere pittance if it weren’t for those in the thrall of Political Correctness and Big Government, not to mention the dirty fucking hippies and the climate “science” community- those flat earthers. Oh, you think I’m joking:

Faced with these two options [emissions reductions and geo-engineering], most people would aggressively explore the latter solution (while possibly also investing in the first if the threat were deadly enough).

Unless, of course, the threat we were talking about was global warming. On that issue, a lethal combination of political correctness and entrenched special interests has convinced the chattering classes that the costly, slow and difficult path is the only option, stifling any discussion of cheap, easy and reversible solutions that might be available…

Why, then, are so few people willing to talk about such “geoengineering” solutions? There could be a fear of unintended environmental consequences, although the lack of significant side effects from Pinatubo is encouraging. It might be that this solution just seems too good to be true. Could it really be so simple and cheap? Modern society is in love with costly, complicated solutions. (Governments in particular seem to like them.)…

Devoted environmentalists, meanwhile, as well as some members of the tight-knit climate-science community, find this sort of idea repugnant. Using sulfur dioxide to solve an environmental problem? It just doesn’t feel right to them. Of course, the idea that the Earth revolves around the sun didn’t initially feel right either. Nor did the assertion that the Earth might in fact be round and not flat.

L&D would have you believe that a certain group of people (liberals the Politically Correct, Big Government worshiping, environmentalist, climate science-supporting “chattering classes”) are standing between honest discussion of the merits of the no-brainer geo-engineering fix and the colossal boondoggle of mitigation. L&D- brave, counter-intuitive visionaries that they are- have ridden forth on white steeds to rescue everyone else from the tyranny of those who support reducing greenhouse gas emissions (which is virtually every relevant scientific organization on the planet) and would keep this miracle cure secret.

The only problem with this scenario is that, like much of L&D’s work of late, it’s complete bullshit. It’s a flashy narrative obscuring a much longer, much more complex, much less revolutionary reality in which the real work and discovery is performed not by venture capitalists and their credulous stenographers, but actual scientists doing actual science.

Serious discussion on geo-engineering has gone on for more than a decade (in fact, entire reviews of the history of geo-engineering were published nearly ten years ago):

And geo-engineering isn’t some obscure concept kept alive only by Intellectual Ventures, L&D, and a handful of “scientists outside Seattle”, despite what L&D would have people believe. To the contrary, it’s being discussed now more than ever at the highest levels of the scientific and political communities [all refs published within the last year or so, before the publication of Superfreakonomics and L&D’s claims]:

Moreover, it’s not as though geo-engineering has gone undiscussed in the media. Here is just a sample of recent, in-depth discussions of geo-engineering in major media outlets [again, all recent and published prior to Superfreakonomics and L&D’s claims]:

There are some very good reasons to be wary of engaging in L&D’s vision of geo-engineering. Even if it works flawlessly, it doesn’t address ocean acidification, hydrological cycle disruption , centuries-long commitment or face the built up warming in a matter of decades, etc. And even those who L&D tout as their scientific endorsements like Ken Caldeira and Paul Crutzen believe that geo-engineering is an emergency solution only to be considered after/concomitant with aggressively pursuing mitigation

The truth of the matter is that this is a complex issue demanding more than attending an investment pitch session and calling it done. And rather than presenting a fresh or unconventional take on the subject, L&D are just repackaging the result of decades of research already being considered at the top political and scientific levels as something “new”.

The idea that a cheap, effective, fast solution to the climate problem which doesn’t depend on greenhouse gas reductions is just sitting out there unexamined is absurd on its face, which is why L&D had to invent their tinfoil narrative of geo-engineering somehow being kept from public discourse by the mighty Political Correctness/Greenie Lobby. I’m almost embarrassed for L&D. They could have just admitted that they shot their mouths off about something they were clearly ignorant of and issued an update or correction to their book. It might be a blow to their perceived credibility, such as it is, but at least they’d show themselves to be serious writers who are more interested in getting things right than giving others the impression they’re in possession of some unconventional wisdom everyone else lacks.

Apparently L&D have decided against the sane, honorable path, and are instead engaging in a media blitz that is an unstable blend of careful walk-back (note their present denial of their book’s cooling claims) and attack on those who had the temerity to suggest they said anything wrong in the first place- all the while still maintaining that geo-engineering is every bit as Awesome as they wrote about in Superfreakonomics.

In Part Two, I plan on addressing the actual scientific merits of L&D’s favored geo-engineering solution, as well as its drawbacks.

Oceans and Freshwater Reservoirs, and Geo-engineering

Geo-engineering and ocean acidification

[UPDATE: Ken Caldeira has responded in the comments, so be sure to read his response.]

[I intended to post on this Monday, but personal obligations as well as the remarkable events in Iran and online, have been taking up a lot of my time. Then the NPR piece posted on Tuesday, and so on. This isn’t a finished post, just the bones of it.]

Jamais Cascio has a piece in the Wall Street Journal regarding the need to seriously address geo-engineering. It’s a familiar call to arms, one that seems driven by genuine alarm about our lack of short term ability to do anything about climate rather than the tired geo-engineering instead of mitigation anti-regulation smokescreens of the past. And bonus points to Cascio for at least paying lip service to the drawbacks of schemes like sulfate-injections into the stratosphere, including two[!] mentions of ocean acidification:

Also, neither would do anything to solve other problems that arise from excessive levels of carbon dioxide, such as oceans becoming more acidic from increased carbon loading.

Still, we can’t forget: Geoengineering is not a solution for global warming. It would simply hold temperatures down temporarily, doing nothing about the causes of climate change, let alone ocean acidification and other symptoms of a carbon overdose.

In contrast Graeme Wood has a new article on geo-engineering in The Atlantic Monthly that simply doesn’t mention ocean acidification at all (although it nods to consequences from increased acid rain). And NPR has a brief piece on geo-engineering, also focusing on the sulfate aerosol flavor, including some quotes from Ken Caldeira among others that likewise makes no mention of ocean acidification.

This is all the more interesting because Caldeira and Long Cao have of late been doing a lot of work on ocean acidification- I cited one of their more eye-poppingly entitled papers (Coral reefs may start dissolving when atmospheric CO2 doubles) in the Idso/Climate Realists acidification post and Caldeira’s Revelle lecture was basically dedicated to it. To top it off, along with lead author Damon Matthews, they have a new paper out in GRL, Sensitivity of ocean acidification to geoengineered climate stabilization (or here) explicitly addressing this glaring flaw in any sulfate aerosol geo-engineering “solution”.

[The Matthews paper is an interesting read, and I’d have liked to spend more time on it.] Perhaps surprisingly, Caldeira remains a fairly vocal proponent of aggressive geo-engineering research despite his express knowledge that it doesn’t address “the other CO2 problem”; one that his Revelle lecture makes clear he takes quite seriously. Is this a testament to how much worse he thinks warming alone will be, reflective of a concern about tipping points/thresholds, etc., or something else? That’s something I’d love to see addressed the next time someone writes an article on geo-engineering and/or interviews Caldeira.

SEED on geo-engineering, plus credit where credit is due Pielke Jr. edition

SEED, home t0 many disreputable scoundrels, has a piece up with different perspectives on geo-engineering. I haven’t read through all of them (I was mainly interested in what Caldeira had to say), but plan to over the weekend.

Additionally, I admit that I am more than a little critical of Roger Pielke Jr. on this blog, so I thought it worth pointing out that I thought his take was sensible and clearly articulated. It would be easy to spin parts of his comments to champion my own take on the issue or ignore them altogether, but that’s not the way intellectually honest people comport themselves. So, kudos to Roger.