In 2010, Scottish emissions of the basket of six greenhouse gases are estimated to be 55.7 million tonnes carbon dioxide equivalent ( MtCO2e). This is 5.8 per cent higher than the 2009 figure of 52.7 MtCO2e. Between 1990 and 2010, there was a 22.8 per cent reduction in emissions (Table 1, Figure 1).
The available time series for 1990, 1995, 1998-2010 can be found in Annex A and Annex B.
Table 1: Emissions of greenhouse gases
(million tonnes carbon dioxide equivalent)
| || 1990 || 2009 || 2010 || Change from 1990 || Change from 2009 |
| Greenhouse gas emissions excluding international aviation & shipping || 69.7 || 49.8 || 53.2 || -23.6% || 6.9% |
| International Aviation || 0.5 || 1.1 || 1.0 || 118.5% || -6.1% |
| International Shipping || 2.0 || 1.7 || 1.5 || -28.5% || -15.9% |
| Total greenhouse gas emissions including international aviation & shipping || 72.2 || 52.7 || 55.7 || -22.8% || 5.8% |
Figure 1: Total greenhouse gas emissions, 1990, 1995, 1998 - 2010
Coverage of emissions reporting
Greenhouse gas emissions estimates are provided by AEA under contract to the Department for Energy and Climate Change, the Scottish Government, the Welsh Government and the Northern Ireland Department of Environment. Reports are published on the National Atmospheric Emissions Inventory (NAEI) website and the latest figures are published in
Greenhouse Gas Inventories for England, Scotland, Wales and Northern Ireland: 1990 - 2010
The basket of greenhouse gases consists of carbon dioxide, methane, nitrous oxide, and the three F-gases (hydrofluorocarbons- HFCs, perfluorocarbons - PFCs and sulphur hexafluoride- SF6), all of which are weighted by global warming potential (GWP). The GWP for each gas is defined as its warming influence relative to that of carbon dioxide. Greenhouse gas emissions are then presented in carbon dioxide equivalent units.
The emissions reported are the combination of emissions minus removals from the atmosphere by carbon sinks. Carbon sinks are incorporated within the three sectors of agriculture and related land use, development, and forestry, which include emissions as well as removals resulting from afforestation, reforestation, deforestation and forest management together with changes between grassland, cropland and settlements.
Reporting of emissions for Scotland excludes any allowance for those UK emissions not allocated to one of the four countries, Scotland, England, Wales or Northern Ireland. Such emissions are mainly emissions resulting from offshore activity.
The total emissions reported here include emissions resulting from international aviation and shipping. The data presented for international shipping are regarded as preliminary estimates, as there is limited data availability for regional marine shipping fuel use. The data presented above for international aviation are regarded to be of low uncertainty. The aviation estimates are based on a database of UK flight movements and detailed calculations of emissions from different phases of flights (take off, cruise and landing cycles). Emissions from international aviation and shipping are recorded as "memo items" in the UK inventory report to the UNFCCC.
All of the sectoral breakdowns included in this statistical release are based on the source of the emissions, as opposed to where the end-user activity occurred. Emissions related to electricity generation are therefore attributed to power stations, the source of the emissions, rather than to homes and businesses where the electricity is used. Similarly the figures include emissions related to goods produced in Scotland and then exported abroad but do not include emissions related to the production of goods that are imported into Scotland.
The sector breakdowns used in this report are primarily based on the National Communication (NC) sectors. However, in order to associate emissions from conversion of grassland to and from cropland and liming of agricultural land with other agricultural activities we have generated three new sectors from the previous two sectors Land Use, Land Use Change and Forestry (LULUCF) and Agriculture. The first new sector Agriculture and related land use includes all emissions in the NC sector Agriculture together with those LULUCF emissions associated with agricultural practices. The remaining LULUCF emissions are grouped into Forestry (changes in emissions relating mainly to stock changes resulting from afforestation, deforestation and harvested wood products) and Development (changes in emissions resulting from land use change to settlements). These new sectors are the same as those that were reported in the Scottish Government publication "Low Carbon Scotland - Meeting the Emissions Reduction Targets 2010-2022". A detailed mapping between the sectors used in this report and the NC sectors and Intergovernmental Panel on Climate Change (IPCC) sectors is given in Annex E.
Revisions to the Inventory
Scottish greenhouse gas emissions are reviewed every year, and the whole historical data series is revised to incorporate methodological improvements and new data.
It is therefore not appropriate to compare the inventory from one year with that from another - the latest inventory represents a single consistent data series going back to 1990 (excluding 1992-1994 and 1996-1997).
The revisions to the inventory have resulted in revisions to the 2009 figures and the entire time series. The total of all Scottish greenhouse gas emissions in 1990 (including international aviation and shipping) has been revised upwards from 71.6 to 72.2 MtCO2e. In 2009 the figure has been revised up from 51.0 to 52.7 MtCO2e. Comparing the 2010 figures with the 2009 figures published a year ago will therefore give a different year-on-year percentage change, but one which is incorrect and should not be used.
The main changes to the 2009 figures are:
- Business: (1.007 MtCO2e increase) predominantly due to a revision to industrial combustion allocation of other petroleum gas (OPG - mainly ethane) use in Scotland across the inventory time series and revisions to energy mapping grids in the industry and commercial sectors through use of new data on UK sector energy use and an updated Inter-Departmental Business Register. These changes have increased estimates for industrial combustion by around 0.500 MtCO2e in Scotland in 2009. In addition, revisions to the UK-wide model for emissions of HFCs from refrigeration and air conditioning equipment have increased the estimates for Scotland in 2009 by 0.256 MtCO2e.
- Energy Supply: (0.324 MtCO2e increase) primarily from the revision of OPG use in petroleum refining and revisions to gas oil allocations to the upstream oil and gas sector. This sector has also seen a reduction in estimates for 2009 of emissions from closed coal mines due to updated analysis from the update to closed coal mine emission estimates.
- Waste Management: (0.149 MtCO2e increase) from revisions to the UK waste model and also revisions to use more DA-specific input data to derive country-specific estimates
Annex D provides differences for each of the sectors for 1990 and 2009. More details are provided in Appendix 7 of Greenhouse Gas Inventories for England, Scotland, Wales and Northern Ireland: 1990-2010.
There are uncertainties associated with all estimates of greenhouse gas emissions. However, although for any given year considerable uncertainties may surround the emissions estimates for a pollutant, it is important to note that trends over time are likely to be much more reliable.
The approximate 95 per cent confidence interval for Scottish greenhouse gas emissions in 2010, excluding international aviation and shipping, is estimated to be ±27 per cent of the mean (The estimates for international aviation have low uncertainty, while those for international shipping have high uncertainty). The approximate 95 per cent confidence interval for the trend in such greenhouse gas emissions between the 1990 base year and 2010 is between -32 per cent and -14 per cent around a central estimate of -24 per cent. More details are provided in Appendix 1 in Greenhouse Gas Inventories for England, Scotland, Wales and Northern Ireland: 1990-2010
Sources of emissions
In 2010, 37 per cent of greenhouse gas emissions were from the energy supply sector, 19 per cent from transport (excluding international aviation and shipping), 19 per cent from agriculture and related land use, 15 per cent from residential and 14 per cent from business. Emissions from international aviation and shipping accounted for 4 per cent of emissions and waste management (mainly landfill) emissions also 4 per cent (Figure 2a, Table 2). Development and public emissions accounted for 3 and 2 per cent respectively. These figures total more than 100 per cent due to the effect of net removals from the forestry sector (accounting for -17 per cent of overall emissions). More detail is given in Annex A.
Figure 2a: Greenhouse gas emissions by source: 1990, 1995, 1998 - 2010
Million tonnes of carbon dioxide equivalent
Since 1990, emissions from transport (excluding international aviation and shipping) have increased by 0.2 MtCO2e (2 per cent). Residential emissions also saw an increase of 0.2 MtCO2e, a 3 per cent increase since 1990. The largest absolute reduction was for the business and industrial process sector at 5.3 MtCO2e, a 40 per cent reduction, mainly as a result of the closure, in 1992, of Ravenscraig iron and steel plant and the relocation, in 1995, of a site manufacturing nitric acid from Leith to Ireland. Other sectors with significant reductions are waste management down 4.4 MtCO2e (67 per cent reduction), agriculture and related land use down 3.8 MtCO2e (27 per cent) and energy supply down 1.6 MtCO2e (7 per cent). Development emissions decreased by 0.2 MtCO2e (9 per cent) and emissions from international aviation and shipping decreased by 0.02 MtCO2e (1 per cent). Net removals from forestry increased by 1.3 MtCO2e; 15 per cent more than removed in 1990. (Figure 2b).
Figure 2b: Greenhouse Gas Emissions by source 1990, 1995, 1998 - 2010
million tonnes of carbon dioxide
Between 2009 and 2010, there were large increases in greenhouse gas emissions in the energy supply and residential sectors, of 2.2 and 1.1 MtCO2e (12 and 15 per cent respectively). This was primarily due to a rise in fossil fuel heating in the residential sector, combined with an increase in electricity generation from coal fired power stations. Emissions from the residential and public sectors are affected by changes in weather among other factors. 2010 was, on average, the 10th coldest in the period since 1910. In particular, the average temperature for the six months January-March and October-December was the coldest since 1919. 2010 was also the driest year since 2003 resulting in a drop of hydro-generation in Scotland of 33% between 2009 and 2010 and as a result renewable energy generation overall decreased. In addition there were reductions in output from gas and nuclear, likely attributable to a rise in gas prices (making gas generation relatively less economic) and planned maintenance outages respectively. Electricity generated by coal increased by 23% from 2009 to 2010.
Net removals from the forestry sector reduced in size from 10.0Mt2e to 9.6 MtCO2e (a 4 per cent reduction and 0.4 MtCO2e decrease) between 2009 and 2010. There were increases in emissions of 2 per cent from the business and industrial process sector (0.1 MtCO2e) while the public sector saw a 3 per cent rise (0.03 MtCO2e). International aviation and shipping showed the largest per cent reduction in emissions at 12 per cent (down 0.3 MtCO2e). Net emissions from agriculture and related land use and waste management both decreased by 3 per cent (0.3 MtCO2e and 0.1 MtCO2e respectively), while transport (excluding international aviation and shipping) and development emissions both reduced by 1 per cent (0.1 MtCO2e and 0.01 MtCO2e respectively).
Table 2: Scottish greenhouse gas emissions by source: 2010 share, 2010 comparisons with 1990 and 2009
| National Communication Sectors || % share of 2010 || %change from 1990 || %change from 2009 |
| Energy Supply || 37% || -7% || 12% |
| Transport (excluding IA&S) || 19% || 2% || -1% |
| International Aviation and Shipping (IA&S) || 4% || -1% || -12% |
| International Aviation || 2% || 118% || -6% |
| International Shipping || 3% || -29% || -16% |
| Business and Industrial Process || 14% || -40% || 2% |
| Business || 13% || -33% || 2% |
| Industrial Process || 1% || -79% || -4% |
| Residential || 15% || 3% || 15% |
| Public || 2% || -29% || 3% |
| Waste Management || 4% || -67% || -3% |
| Development || 3% || -9% || -1% |
| Agriculture and Related Land Use || 19% || -27% || -3% |
| Forestry || -17% || 15% || -4% |
| Total greenhouse gas emissions || 100% || -23% || 6% |
Emissions by gas
Carbon dioxide is the main greenhouse gas, accounting for around 79 per cent of Scottish greenhouse gas emissions in 2010 when Scottish emissions of carbon dioxide were estimated to be 43.8 MtCO2. This was 7.6 per cent higher than the 2009 figure of 40.7 MtCO2 (Figure 3).
Carbon dioxide emissions have fallen by 17.9 per cent since 1990 and non-CO2 emissions (methane, nitrous oxide and F-gases) have fallen by 36.6 per cent since 1990 (Table 3). More detail is given in Annex B.
Figure 3: Greenhouse emissions by gas, 1990, 1995, 1998-2010
Million tonnes of carbon dioxide equivalent
Table 3 Scottish greenhouse gas emissions by gas: 2010 comparison with 1990 and 2009
| Basket of Greenhouse Gases || Change from 1990 || Change from 2009 |
| Carbon dioxide (CO2) || -17.9% || 7.6% |
| Non-CO2 || -36.6% || -0.3% |
| Total Scottish greenhouse gas emissions || -22.8% || 5.8% |