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Scientific American – Polar Meltdown & Scrubbing Carbon Articles

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The June 2010 issue of Scientific American had two climate-related pieces in it that I thought were worth discussing.

Polar Meltdown

The first dealt with 12 potential events, their likelihood of occurring by 2050 and some of their effects.  The front cover lists ‘Polar Meltdown’ last among the 12.  The article has ‘Polar Meltdown” as the 8th event, despite its likelihood; I don’t really understand how they decided to organize the events.  I mention these details first because more of the general public reads Scientific American than journals or even climate-related blogs.  Given the nature of the effects – vastly more negative than positive – I would personally prefer to see this listed first both on the front cover and in the article.  Interestingly, their online version has this event first, which is good news.

Another quibble: the picture accompanying the little piece is of Antarctica instead of the Arctic.  In terms of “Polar Meltdown”, Antarctica definitely presents the larger long-term threat of the two.  But the article is supposedly about events by 2050.  I’m a climate realist – which means I recognize that Antarctica won’t completely melt by 2050.  That will likely take a century or two.  And it’s not really even the Arctic ice melting that should scare us all – it’s Greenland.  Greenland’s ice has been land-bound for thousands of years.  When that ice melts, it will raise sea levels.  Similarly for Antarctica – it’s not the sea ice melting every year that presents a threat, its 8 times as much ice as exists on Greenland melting that will raise sea levels even higher.  There are plenty of graphics demonstrating the ridiculously fast meltdown that has already occurred in the Arctic.  They should have shown some of those instead of an Antarctica-shaped piece of ice in a punchbowl.  That’s a lousy visual on multiple levels – the most important being water-borne ice melting doesn’t change the level of the water.  Sheesh.

Okay – onto the science part of this potential event.  Scientific America’s author thinks this event ranks as “Likely”, or better than “50-50” but not “certain”.  I’m glad to see the assessment at better than 50-50, because it is.  Given the speed at which Arctic and Greenland ice has already melted, I unfortunately think that Arctic sea ice in particular is within a handful of years of disappearing every summer, as this post details.  Arctic sea ice volume is plummeting towards an effective zero point much, much faster than any expert thought possible just a couple short years ago.  If you go to their online version and click on the ‘polar meltdown’ icon, it takes you to a page describing some effects of the event occurring – none of which appear in the print version, by the way.  There is also a place to vote on how likely you think this event is of occurring.  As of this writing, the highest percentage of respondents (36%) agree with the author.  29% of respondents think it is almost certain.  14%, 11% and 8% think it is ’50-50′, ‘unlikely’ and ‘very unlikely’.  There’s freepers everywhere, I suppose.

Scrubbing Carbon

The second article in the June 2010 Scientific American magazine I wanted to discuss was by Klaus S. Lackner entitled, “Washing Carbon Out Of The Air” (you’ll likely have to go find a paper version of the magazine to read it in full).  The article discusses some efforts of groups around the world working on ways to remove carbon dioxide from the atmosphere in sufficient quantities that the global concentration of CO2 goes down over time.  Lackner works with teams at Columbia University and Global Research Technologies.

In a nutshell, the technology that Lackner is pushing would bind CO2 to filters.  Once loaded, the filters would be moved to a closed chamber where the filter would be “cleaned” with water and the CO2 compressed into liquid form.  The water would be recollected and the filter would be moved back to be exposed to the atmosphere again.  Small prototype systems have been built and successfully operated.  I’m not sure they’re viable on the kinds of scales that would be required to reduce atmospheric CO2 concentrations, however.  Let’s look at some of the details.

While not explicitly specified in the article, a field deployed unit would be about 20 feet tall and at least 20 feet long.  The article cites a stated goal of 10 tons of absorbed CO2 per day by each unit.  To have any measurable effect on global CO2 concentrations, the author envisions 10 million air capture machines deployed worldwide, removing 36 gigatons of CO2 annually, which could reduce concentrations by 5ppm annually.  The author acknowledges that the highest operational costs are involved with removing the CO2 from the filter.  Pumping air out of the CO2 collection chamber and compressing the CO2 from gas to liquid form requires energy.  Left unsaid in the article is the amount of energy required to operate 10 million of these units every day.  I estimate millions of tons of coal based on some back-of-the-napkin calculations.  The author apparently already figured all this out and still ended up with the 10 tons collected per day, but I would argue that important details have been left out so far.

Beyond power requirements, there are obviously water requirements in this design.  There isn’t even the barest mention of the water usage in the prototype machines.  It didn’t read like there were enormous quantities of water required, but in an increasingly drought-stricken world, would these machines pass pragmatic tests of what to do with the little fresh water that remains available for use?  Where is the water going to come from?  How will it be transported to the machines?  How much water is wasted?

The last item I want to point out is one of the author’s stated goals: 10 million of these machines.  He makes sure to mention that the world produces 71 million cars and light trucks every year.   Which sounds great until you take into consideration the fact that cars have been mass-produced for over 100 years now.  When that mass-production started, 71 million weren’t generated in the first 10 years combined.  Aside from the operating restrictions left undescribed, there are simple manufacturing questions that would have to be answered.  It typically takes 10-30 years for a technology to go from research to production to significant market penetration.  One to three decades for the first generation of these machines; additional time beyond that for more efficient technologies that are cheaper to produce and deploy.

I don’t want to be a buzz kill, I just want to define as clearly as possible the real-world requirements that this or any other technology has to overcome in our fight against the climate crisis.  We’re decades behind where we could and should be anyway.  Technologies like this need to be quickly assessed for viability and then much more effort needs to be made to deploy them so that they have time to take effect.  Unfortunately, I still don’t get the sense that there is enough urgency in the public to push for that to happen.  The longer we wait, the tougher the crisis will be to overcome.  Larger, harder problems require more money, by the way.  We’re relegating ourselves to paying more for solutions that will be less effective tomorrow than they are today.

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