U.S.-FocUSed Biochar report - BioEnergy Lists

Where:Q = annual weight of carbon that can be sequestered (we will only use the metric units that are standard inBiochar literature: GtC/yr =giga tonnes carbon per year, where giga = billion = 1.0 E9)P = productivity expressed as dry biomass annual growth per unit area (t biomass/area-yr; t = tones)A = area from which the biomass is annually harvested (area as ha = hectare, gha = gigahectares, Mha = megahectares,and m2 = square meters)F = fraction of carbon in char derivable from the annual biomass growth (typically ¼ =0.25 by weight)In the US, it is most common to talk about the resource base in annual biomass (our primary units), not carbonterms, this may be referred to as feedstock. The former is close to twice the latter. Caution is also urged in makingsure the data comparison is for dry and not green tonnes. Here we use only dry tonnes, whose percentage ofboth biomass and carbon is about twice that of green tonnes.5.3 More detailed projection methodologyA US goal.There have been only a few attempts to project the upper limits of Biochar’s possibannual contribution to carbondioxide (CO 2 ) removal [Read 26 , Lehmann 27 , Lenton 28 ]. In particular, this following analysis has been heavilyinfluenced by recently deceased Professor Peter Read, who seems to have been the first to urge large Biocharnumbers. His proposed global goal total was around 10 gigatonnes Carbon per year (10 GtC/yr). However, weare unaware of any study that allocates a share of the global atmospheric carbon excess to the US. That sharewould seem to be high. Although less than 5% of the global population, until recently with the growth of energyconsumption (and new expanded fossil carbon) in China and India, the US has been consuming about 25 % of theglobal total. 29 But we have nowhere near 25% of the global land area, which is about 13 Gigahectares (Gha). TheUnited States has only about 1 Gha or less than 8% of the global total, and much of the US land area is cold, arid,and/or mountainous. On the other hand, we are the most prosperous nation, and there are substantial benefitsto doing as much as we can, even while paying other countries to help remove the rest of our large legacy share.So, the logical question is: Given the US carbon legacy, what should our percent of the total be and how does thatsquare with the figures from the questions above? This is the subject of the next subsection – in which we showone way to achieve 1 GtC/yr, which is 10% of Prof. Read’s recommended annual total.Biochar units.Biochar units are not yet standardized. Although the US remains on the “English” system (including all of ouragriculture and forestry data), most of the technical Biochar data is expressed in metric terms. We shall stick withmetric units but the following conversions may be helpful:25 Victoria University of Wellington Institute of Policy Studies Working Paper 07/01; Holistic greenhouse gas management: mitigatingthe threat of abrupt climate change in the next few decades. With reviewers comments and author rejoinders; P. Read*and A. Parshotam** Also see a 2008 video of Peter mentioning Biochar is at http://vimeo.com/5666985 (This makes strong connectionto the work of Prof. William Ruddiman on early anthropogenic causation of CO 2 rise.27 Lehmann J, Gaunt J and Rondon M 2006 Bio-char sequestration in terrestrial ecosystems – a review. Mitigation and AdaptationStrategies for Global Change 11: 403-427. DOI: 10.1007/s11027-005-9006-5. [Found at http://www.css.cornell.edu/faculty/lehmann/publ/MitAdaptStratGlobChange%2011,%20403-427,%20Lehmann,%202006.pdf] There are a large number of ProfessorLehmann’s Biochar publications at http://www.css.cornell.edu/faculty/lehmann/publications/index.html28 Lenton, T.M. and Vaughan, N.E. (2009) The radiative forcing potential of different geoengineering options. AtmosphericChemistry and Physics 9, 5539-5561. url: http://www.atmos-chem-phys.net/9/5539/2009/.29 http://pdf.wri.org/navigating_numbers_chapter6.pdf (Fig. 6.1) http://www.docstoc.com/docs/976444/CARBON-DIOXIDE-AND-OUR-OCEAN-LEGACY/Biochar GHG reduction accounting in: Potential Biochar Greenhouse Gas Reductions53