Greenhouse gas inventories or GHG inventories are emission inventories of greenhouse gas (GHG). Scientists use inventories of natural and anthropogenic (human-caused) GHG emissions as tools when developing atmospheric models. Policy makers use inventories to develop strategies and policies for emissions reductions and to track the progress of those policies. Regulatory agencies and corporations also rely on inventories to establish compliance records with allowable emission rates. Businesses, the public, and other interest groups use inventories to better understand the sources and trends in emissions. Unlike some other air emission inventories, greenhouse gas inventories include not only emissions from source categories, but also removals by carbon sinks. These removals are typically referred to as carbon sequestration. Greenhouse gas inventories typically use global warming potential (GWP) values to combine emissions of various greenhouse gases into a single weighted value of emissions.
Examples Some of the key examples of greenhouse gas inventories include:
All Annex I countries are required to report annual emissions and sinks of greenhouse gases under the United Nations Framework Convention on Climate Change (UNFCCC) National governments that are Parties to the UNFCCC and/or the Kyoto Protocol are required to submit annual inventories of all anthropogenic greenhouse gas emissions from sources and removals from sinks. The Kyoto Protocol includes additional requirements for national inventory systems, inventory reporting, and annual inventory review for determining compliance with Articles 5 and 8 of the Protocol. Project developers under the Clean Development Mechanism of the Kyoto Protocol prepare inventories as part of their project baselines.
Greenhouse gas emissions accounting
Greenhouse gas emissions accounting is measuring the amount of greenhouse gases (GHG) emitted during a given period of time by a polity, usually a country but sometimes a region or city. Such measures are used to conduct climate science and climate policy. There are two main, conflicting ways of measuring GHG emissions: production-based (also known as territorial-based) and consumption-based. The Intergovernmental Panel on Climate Change defines production-based emissions as taking place “within national territory and offshore areas over which the country has jurisdiction”. Consumption-based emissions take into account the effects of trade, encompassing the emissions from domestic final consumption and those caused by the production of its imports. From the perspective of trade, consumption-based emissions accounting is thus the reverse of production-based emissions accounting, which includes exports but excludes imports (Table 1). The choice of accounting method can have very important effects on policymaking, as each measure can generate a very different result. Thus, different values for a National greenhouse gas Emissions Inventory (NEI) could result in a country choosing different optimal mitigation activities, the wrong choice based on wrong information being potentially damaging. The application of production-based emissions accounting is currently favoured in policy terms as it is easier to measure, but it is criticised in the literature principally for its inability to allocate emissions embodied in international trade/transportation and the potential for carbon leakage. Almost all countries in the world are parties to the Paris Agreement, which requires them to provide regular production-based GHG emissions inventories to the United Nations Framework Convention on Climate Change (UNFCCC), in order to track both countries achievement of their nationally determined contributions and climate policies as well as regional climate policies such as the EU Emissions Trading Scheme (ETS), and the world's progress in limiting global warming.
Comparison of production based and consumption-based accounting
Over the last few decades emissions have grown at an increasing rate from 1.0% yr−1 throughout the 1990s to 3.4% yr−1 between 2000 and 2008. These increases have been driven not only by a growing global population and per-capita GDP, but also by global increases in the energy intensity of GDP (energy per unit GDP) and the carbon intensity of energy (emissions per unit energy). These drivers are most apparent in developing markets (Kyoto non-Annex B countries), but what is less apparent is that a substantial fraction of the growth in these countries is to satisfy the demand of consumers in developed countries (Kyoto Annex B countries). This is exaggerated by a process known as Carbon Leakage whereby Annex B countries decrease domestic production in place of increased importation of products from non-Annex B countries where emission policies are less strict. Although this may seem the rational choice for consumers when considering local pollutants, consumers are inescapably affected by global pollutants such as GHG, irrespective of where production occurs. Although emissions during the 2008 financial crisis, the longer-term trend of increased emissions has resumed. Today, much international effort is put into slowing the anthropogenic release of GHG and resulting climate change. In order to set benchmarks and emissions targets for - as well as monitor and evaluate the progress of - international and regional policies, the accurate measurement of each country's NEI becomes imperative.
Production-based accounting
… excerpt ends here. Continue reading the full article.
