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Hi GHG Experts Network,<br>
<br>
I’m hoping to confirm a methodology for converting carbon to
CO2-equivalent for an estimate of gross emissions resulting from
tropical deforestation. I’ve looked at the LULUCF Good Practice
Guidance, but have found more useful using a paper by Fearnside (2000)
[Global Warming and Tropical Land-Use Change: Greenhouse Gas Emissions
from Biomass Burning, Decomposition and Soils in Forest Conversion,
Shifting Cultivation and Secondary Vegetation. <i>Climatic Change</i>
46: 115-158.]<br>
<br>
In the paper, the author concludes that the total emissions for
land-use change (not considering uptake of intact forest, recurrent
burning of savannas or fires in intact forests) is equal to “2.4 x 10^9
t C, equivalent to 2.4–2.9 x 10^9 t of CO2-equivalent carbon."<br>
<br>
Am I reading this correctly? What is the difference between
“CO2-equivalent carbon” and simply “CO2-equivalent”? <br>
<br>
A back of the enveloped calculation using emission factors for CO2, CH4
and N2O accounting for burning and biomass decay (see top of Table XIII
in Fearnside (2000)) and converting by GWP would suggest that 2.4 x
10^9 t C is equal to about 7.9 - 9.1 x 10^9 t CO2-equivalent. That is,
the emission factor is 3.3-3.8, while the paper above suggest
approximately 1. Why this difference? Is this because Fearnside is
assessing net emissions while I am interested in gross emissions (ie,
without accounting for offsite carbon uptake)?<br>
<br>
I realize there might be some differences in emission factors resulting
from the variability of biomass burning, including a need to account
for variability in fire intensity and charcoal production. But I just
want to confirm that I’m not an order of magnitude off if I’m trying to
estimate gross emissions from data describing the pre- and post-burn
carbon stock per ha (tC/ha) from a chronosequence of tropical forests
in central Africa subject to swidden agriculture. <br>
<br>
If you would have any insights, please let me know.<br>
<br>
Thanks!<br>
<br>
Mark<br>
<pre class="moz-signature" cols="72">--
*********************************
Mark Purdon, PhD Candidate
Department of Political Science
University of Toronto
Sidney Smith Hall, Room 3018
100 St. George Street
Toronto, Ontario M5S 3G3, Canada
Cell: +1 (647) 300-3990
Fax: +1 (416) 978-5566
Email: <a class="moz-txt-link-abbreviated" href="mailto:mark_purdon@fastmail.fm">mark_purdon@fastmail.fm</a>
Skype: mark.purdon
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