Submitted to: Meeting Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 12/2/2009
Publication Date: 12/4/2009
Citation: Bogner, J., Spokas, K.A. 2009. IPCC Methodologies for the Waste Sector: Past, Present, and Future [abstract]. Oral Presentation for the DAKOFA/ISWA Waste & Climate Conference. Dec. 3-4, 2009. Copenhagen, Denmark. Parallel session 2: From life cycle thinking to acting Title: IPCC Methodologies for the Waste Sector: Past, Present, and Future. Online reference: http://www.wasteandclimate.org/DocumentDownloadServlet?id=85&language=en. On-line. Interpretive Summary:
Technical Abstract: The reporting of national greenhouse gas (GHG) emissions began more than a decade ago by the signatory countries of the United Nations Framework Convention on Climate Change (UNFCCC). National GHG inventories rely on the evolving Intergovernmental Panel on Climate Change (IPCC) national GHG inventory methodologies developed through the IPCC Task Force on National GHG Inventories. Based on literature surveyed for the IPCC 4th Assessment Report, the waste sector contributes <3% of total global anthropogenic GHG emissions (Bogner et al., 2007). The global total of approximately 49 Gt CO2 eq/annum includes carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases normalized to their respective 100-year global warming potentials from the IPCC 2nd Assessment Report [used for Kyoto compliance]. Based on current methods, about 90% of the current waste sector emissions can be attributed to CH4 from landfills and wastewater. In general, the IPCC methodologies rely on carbon (C) and nitrogen (N) balances with careful coordination between the waste sector and other sectors (industry, agriculture, transport, energy, forestry) to avoid overlaps and double counting. For the waste sector, only CH4 and N2O, plus the carbon dioxide (CO2) from the incineration of fossil carbon (plastics, synthetic rubber, synthetic textiles, etc.) are included in IPCC methodologies. The “biogenic” CO2 (from incineration of biomass, from composting operations, or produced anaerobically as biogas) is considered part of the natural C cycle and therefore accounted for using Land-Use/Land-Use Change & Forestry (LULUCF) methodologies. Landfill C storage is reported as an information item within the waste sector but credited to the Harvested Wood Products sector. Major differences exist between the IPCC methodologies, LCA (life cycle analysis) approaches, and a wide variety of regional, urban, industrial/corporate, and personal GHG accounting methods. In general, the IPCC methodologies focus on direct annual country-based GHG emissions from post-consumer waste. Other methods focus on alternative temporal and spatial dimensions, may include indirect emissions associated with upstream and downstream activities, and may also include biogenic CO2. Therefore, it is extremely important to fairly compare estimated emissions from various technologies using coordinated, consistent & transparent methodologies, assumptions, and input data. Historically, estimated GHG emissions from waste based on IPCC and other methodologies have had high uncertainties due to both methodological and data issues, including missing data and data inconsistencies. In addition, as the scale and scope of field measurements are increasing, the limitations of IPCC and other estimation methods with little field validation are becoming apparent. For the future, improved field-validated methods and coordinated data for national GHG accounting are necessary and feasible to reduce current uncertainties.