All the targets will use the National Atmospheric Emissions Inventory (NAEI) disaggregated greenhouse gas (GHG) inventory and estimates of greenhouse gas emissions from international aviation and shipping as the main evidence source.
Information on trading in carbon units under the European Union Emissions Trading System (EU ETS) are collected by the Scottish Environment Protection Agency and the Environment Agency (EA).
The inventory data are those currently published by AEA (Environment) under contract to Department of Energy and Climate Change (DECC), Scottish Government (SG), Welsh Government and Department of the Environment in Northern Ireland. AEA conduct detailed quality assurance. The disaggregated data are not National Statistics, but the UK data on which the disaggregations are made are National Statistics.
Detailed data on carbon units traded in the EU ETS are collected by the EA.
Statistics on adjusted emissions will be published in the environment statistics section of the SG website:
The emissions figures are those published in "Greenhouse gas inventories for England, Scotland, Wales and Northern Ireland" on the NAEI website.
The indicator will use the sum of the greenhouse gas emissions assigned to Scotland in the disaggregated greenhouse gas inventory (taking account of any removals such as those resulting from afforestation) and the emissions from international aviation and shipping, expressed as tonnes of carbon dioxide equivalent. Changes to the estimation methodology may result in changes to the published emission figures for previous years.
This figure will be adjusted to take account of carbon trading by comparing the number of carbon units surrendered with the nominal allocation of units to Scotland. For the period 2005-2007 (Phase I of the EU ETS), in addition to units allocated to individual sites, Scotland will also take responsibility for a share of any UK allocation that is auctioned. The share to be used will equate to: Allocated units to Scottish sites/Allocated units to UK sites. The allocated units to be used will be those allocated for the year in which the auction takes place. For Phase I of the EU ETS, where a small amount of unused units from the New Entry Reserve were auctioned in 2007 (and where DECC have allocated the sales equally over the period 2005-2007), the units to be used will be those allocated for the whole of Phase I.
Nominal Scottish allocations for the period 2008-2020 have been published by the Committee in Climate Change in Table 1.4 of the Technical Appendix accompanying their report "Scotland's path to a low-carbon economy" ( http://downloads.theccc.org.uk/Scottish%20report/Technical%20Appendix%20Scotland%20v2.pdf). The nominal allocations for the period 2010-2012 were published in May 2010 as "specified amounts" in "The Carbon Accounting Scheme (Scotland) Regulations 2010" ( http://www.opsi.gov.uk/legislation/scotland/ssi2010/pdf/ssi_20100216_en.pdf).
The regulations require Scottish Ministers to determine whether the total amount of carbon units surrendered in respect of Scotland as a result of the operation of the EU ETS in the relevant period for that year is more or less than the specified amount. Sites are require to surrender units to equate to their emissions in a given year. In some cases units surrendered may not match emissions - for example due to operator error double the units necessary may be surrendered - in such cases the shortfall/excess is offset the following year. For such sites, rather than simply use the number of units surrendered we have used the number of units necessary to be surrendered to satisfy EU ETS compliance for the reporting year which equates to the amount emitted. As for other sites the number of units surrendered already equates to emissions, the effect is to compare actual emissions from ETS sites with the specified amount.
In summary, net greenhouse gas emissions are thus computed:
Net greenhouse gas emissions =
greenhouse gas emissions + units allocated - ETS emissions