Effective climate policy and action depends on a scientifically sound, transparent and comprehensive greenhouse gas (‘carbon’) accounting system. The present system is based on international rules set through the UNFCCC (United Nations Framework Convention on Climate Change) with guidance from the Intergovernmental Panel on Climate Change (IPCC). Domestically, the Department of Climate Change develops the methodologies for Australia’s accounts, maintains the accounts and prepares annual reports for the UNFCCC and the Kyoto Protocol.
The aim of the accounting system is to monitor and report anthropogenic (human-induced) greenhouse gas emissions and removals (’removals’ means carbon dioxide removed from the atmosphere by growing vegetation). Two sets of accounts are produced each year. The ‘UNFCCC’ accounts are moving towards a comprehensive coverage of emissions and removals but the ‘Kyoto’ accounts, dating back to when the Kyoto Protocol was negotiated in the 1990s, are incomplete. In Australia’s case, major omissions include emissions from logging native forests and all impacts of land use on CO2 emissions and removals with the exception of emissions from landclearing since 1990, and removals by plantations and reforestation since 1990. Soil carbon is excluded in most cases. It is the incomplete Kyoto accounts that govern the Kyoto targets and which have been the primary basis for international negotiations.
A sound carbon accounting system needs four elements: a comprehensive and clear framework based on carbon cycle science; reliable methodologies for data collection; an independent agency responsible for the system; and credible independent auditing. A shortfall in any of these elements creates distortions that degrade the effectiveness of climate policy and action, and may be strongly counter-productive (e.g. clearing tropical rainforests to grow palm oil; conceptualising tree planting or revegetation as an ‘offset’ for fossil carbon emissions).
Some issues with the current accounting system are outlined here. Primarily they relate to the treatment of land use and agriculture.
Framework
The current accounting framework is limited to greenhouse gas flows. This is adequate for fossil carbon (coal, oil, gas) where, from a climate perspective, the stocks are not relevant if they remain in situ. But for biocarbon, the carbon associated with living ecosystems, stocks are crucial. The landscape stores enormous amounts of carbon in vegetation and soil. Annual fluxes in these stocks caused by natural events (e.g. drought, flood, insect attack, wildfire) often exceed anthropogenic (human-caused) fluxes. Not only is it difficult if not impossible to measure these fluxes annually, it is even more difficult to distinguish what portion is anthropogenic and therefore capable of being acted upon; it is anthropogenic emissions that are required by international agreements to be measured (the current IPCC guidance assumes all fluxes on ‘managed land’ to be anthropogenic).
A second issue with the current framework is that it is annual. Again, this suffices for fossil carbon where all flows are emissions. But for land use, land-use change and forests, flows comprise emissions and removals. This introduces a time dimension that needs to be accounted for: for example, it is not adequate to assume that logged forest regrows and therefore treat logging as ‘carbon-neutral’. The issue is how long the emissions caused by logging remain in the atmosphere, given the imperative for global emissions to peak by 2015. If decades or centuries old forests are logged or cleared, it will take decades or centuries to recapture the carbon.
A Green Carbon Accounting Framework is proposed that takes a ‘stock-centric’ approach to biocarbon accounting. The preparation of carbon stock accounts for the land-use sector, switches the policy focus from short-term flows to actively maintaining stocks, reducing risks of stock depletion, and encouraging restoration. For the complementary flow component of the accounts, the green carbon framework improves transparency by clearly separating fossil carbon from biocarbon. Biocarbon is further disaggregated into ‘green’ carbon, permanently stored in natural ecosystems, and ‘production’ carbon in agricultural systems, including tree farms and plantations. Australia could adopt such a system without waiting for international agreement, provided it is structured such that reports can be prepared in accordance with international requirements.
Data. In Australia, (flow) accounts for the land use, land-use change and forestry section of the accounting system are mostly derived from a model: the National Carbon Accounting System (NCAS) which combines remote sensing data with information about climate, soils, land use and management. It is a model, not a measurement. Furthermore, even though the flow accounts are actually calculated as annual stock changes, emissions and removals are not separately tracked; only net carbon stock changes are reported. ANU scientists found eucalypt forests in south-eastern Australia storing over 1800 tonnes of carbon per hectare in living and dead biomass, the highest known densities in the world. They also found that NCAS generally underestimates carbon storage in largely undisturbed natural forests, potentially by very large amounts (Mackey et al, 2008).
Responsibility
In Australia the Department of Climate Change is responsible for greenhouse accounting (framework and data collection) as well as advising on climate policy and implementing climate programs. For the system of national (economic) accounts, the Australian Bureau of Statistics (ABS) collects and presents statistics about the economy, independent of Treasury which advises on policy. A similar approach should be adopted for greenhouse accounts.
Auditing
When Australia adopts a compliance policy for reducing greenhouse gas emissions a rigorous independent auditing regime will be needed. This will be particularly challenging if land-use, land-use change and forestry are included.
Background documents
April 2009. Working paper 4. Australia’s national greenhouse accounts re-arranged for policy coherence. Based on Australia’s 2006 accounts (which do not include climate data for croplands and grasslands); data on emissions and removals are rearranged to separate fossil carbon from biocarbon, and green carbon from production carbon. Emissions and removals are disaggregated (the government accounts only give net figures). Difficulties with terminology are highlighted: for example, ‘forestry’ in the Kyoto accounts only includes net emissions from trees planted since 1990; it does not include native forest logging.