Wednesday, December 16, 2009

Introduction to Carbon Footprinting: Part 1

I learned a new term recently:  Vaporware. 
Vaporware is a product that has been announced, but does not actually exist yet.  What I like about vaporware is that it inspired me to think of yet another possible class to teach in the School of Comparitive Irrelevance (e.g. Urban Planning for the Roma, and Grammar of Solecisms, or my personal submission: Nerfherding for Agoraphobes).  

So, I wondered about a class called Carbon Footprinting of Vaporware.  The question is-- can something that does not exist have a carbon footprint? 

The question, at this point, is an academic one, since most of what we're concerned about in the carbon footprinting world is big heavy manufactured, transported, and/or processed stuff that we consume or exploit. 

Given that oh-so-pithy introduction, this blog posting actually goes out to Carbon Footprints and its sprawling uncle, Life Cycle Assessment.  These are ginormous topics that will be the equivalent of Accounting for Environmentalists in a future environmental catastrophe constrained planet.  In the near future, we may just have a carbon-dioxide limit, but we'll see how that goes soon enough. 

By the way, I've just Googled "Coping with Copenhagen" and we're up to 592,000 non-unique hits! 

Introduction--written by Chris Stiedemann (former uber-intern)
    A glimpse of energy statistics reveals that US buildings' utility consumption represent upwards of 50% of CO2 emissions each year. Not included in this statistic, however, are construction-related emissions. A recent EPA report reveals that work done on construction sites releases another 6% of US annual emissions; include material supply and that percentage increases even more. Cement and lumber production alone account for another 10% of US annual emissions. 
While these numbers encompass all sorts of projects from highways to highrises, you can begin to understand that the environmental impact of any new building extends well beyond the bottom line of the utility bill.  1  2    
What is a "Carbon Footprint"?
What We Need is the Imperialization of Metrics  
Some who happen to read this far, and who happened to be well versed in carbon accounting really need not read any further.  The intended audience is someone who doesn't get to interact much with carbon footprinting or have any kind of academic background in it.  
Carbon Footprint is short for "the equivalent global radiative forcing from atmospheric emission of carbon dioxide." 
I'm going to take a pedagogically risky choice here, and start with an example from the real world literature, thereby bypassing some of the usual introductory contexts.  The first thing I want you to take away from this, for your literacy, is that carbon dioxide is not the same as carbon.  Why that's important is that sometimes you'll see something confusing like this:
"Chexxon Oil emitted 2 million tons of carbon last year in the form of methane"  
Frick.  This is rather unfortunately ambiguous.
--Did they mean 2 Megatons of carbon as weighed in the molecule of methane (CH4), or did they mean a global warming potential (GWP) of CO2 as measured in the carbon in the CO2, or did they mean the equivalent GWP in CO2?  The differences can be profound--
2 megatonnes (metric) of carbon as weighed by the carbon content of methane would be:  2 [MTonnes C] x 16/12 [mass of CH4/mass of C] x 23 [GWP equivalency to CO2]= 61 Megatonnes of equivalent CO2.  Admittedly, I've never seen this interpretation, but it is technically possible.
2 megatonnes of Carbon as weighed by the carbon content in CO2:
2 [MTonnes C] x 44/12 [mass of CO2/mass of C] = 7.3 Megatonnes of CO2  
2 Megatonnes of CO2= 2 Megatonnes of CO2 equivalent
--And by tons-- did they mean "short tons" (2000 lbs), "long tons" (2240 lbs), "metric tons" (1000 kg), or "ton longweight" (2400 lbs)?
So, let this be my entreaty to y'all (or a call for protocol) to avoid these kinds of vaguenesses common in popular literature on climate change.  
Be clear that you're talking about equivalent CO2 emissions.
And be clear about the metric (imperial or otherwise).

That's it for now--
Next up-- Global Warming Potential 

1 Quantifying Greenhouse Gas Emissions from Key Industrial Sectors in the United States. May 2008. US EPA. (pages 21,33, 45)

2 Fergus Garber Group

3 Quantifying Greenhouse Gas Emissions from Key Industrial Sectors in the United States. May 2008. US EPA. (pages 21,33, 45)

4 Fergus Garber Group

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