UK's Carbon Footprint 1990 - 2009
UK’s carbon dioxide (CO2) footprint has fallen again according to data released today.
- Between 2008 and 2009, the UK’s carbon dioxide footprint fell by 9 per cent.
- This follows a steady rise of 35 per cent between 1995 and 2005, leaving the footprint in 2009 some 20 per cent higher than it was in 1990
- Over the whole period, carbon dioxide emissions relating to imports doubled and emissions relating to the consumption of goods and services produced in the UK decreased by 10 per cent
- The findings released today also indicate that the UK’s total carbon footprint, including other greenhouse gases (GHG), increased by 12 per cent between
- 1990 and 2009
The carbon footprints reported in this release relate primarily to carbon dioxide emissions, although more experimental estimates of the total greenhouse gas (GHG) emissions are also presented. In this release a carbon footprint refers to emissions that are associated with the spending of UK residents on goods and services, wherever in the world these emissions arise, and those which are directly generated by UK households through private motoring etc. These emissions are often referred to as ‘consumption emissions’ to distinguish them from estimates relating to the emissions ‘produced’ within a country’s territory or economic sphere.
To find out what effect UK consumption has on carbon emissions we need to take into account where the goods we buy come from. Since 1990, the UK economy has continued to move from a manufacturing base towards the services sector. As a result, more of the goods and services we buy and use are now produced overseas.
Inherently the emissions relating to overseas production of imports to the UK are not as easily measured as emissions generated within the UK borders. There are general conventions on how to do this, using shares of production based on financial data, but the results cannot be viewed as being as robust as the estimates of carbon emissions generated domestically.
Carbon dioxide emissions associated with UK consumption
The UK’s carbon dioxide (CO2) footprint can be separated into two components: those emissions relating to goods and services produced by UK business and consumed by UK residents, and those emissions relating to imported goods, often referred to as emissions that are ‘embedded’ in imports.
Figure 1 CO2 emissions associated with UK consumption 1990 to 2009
Figure 1 shows that CO2 emissions associated with imported goods and services accounted for around a quarter of the carbon dioxide footprint in 1990 (166 million tonnes (mt) CO2, 27 per cent); by 2009 their share had increased to just under half (331 mt CO2,
45 per cent).
CO2 emissions from our consumption of UK produced goods and services (excluding exports) and from households’ direct emissions from car use and heating (excluding electricity) are relatively constant across the time series: the main change has been the fall of 10 per cent between 2008 and 2009. This fall can be attributed to a number of factors. There was a significant reduction in emissions from power stations, largely due to a fall in demand but also in part due to an increase in the use of nuclear power for electricity generation. There was also a large reduction in emissions from heavy goods vehicles, and a noticeable fall in emissions from construction activity.
Figure 2 Comparison: consumption based CO2 emissions in 1990 and 2009
Table 1 Description of consumption emissions from the main activities in Figure 2
As well as an overall increase in emissions over the last 20 years, the composition of the carbon dioxide footprint has changed. Figure 2 sets out the changes in each of the five main activities that make up the total carbon dioxide footprint. The increase in emissions embedded in goods and services between 1990 and 2009 is related to increased spending, offset by improvements in the carbon efficiency of production and a switch to less carbon
intensive products1.
Emissions associated with UK production, excluding those directly generated by households, decreased by 14 per cent between 1990 and 2009. UK produced goods and services accounted for 36 per cent of the total CO2 footprint in 2009, compared with 50 per cent in 1990.
Emissions associated with imports, both those directly used by consumers and those used by businesses, account for the increase in the UK’s carbon footprint over the period. Emissions embedded in imports used by businesses for UK consumption more than doubled, and emissions associated with the production of imports used directly by UK consumers increased by nearly 80 per cent. This reflects how we are increasingly importing relatively carbon intensive goods. We are also buying more, and a wider variety of products.
The absolute amount of emissions generated directly by households has remained relatively constant at 139 mt CO2 in 1990 and 140 mt CO2 in 2009. Within the category, emissions from heating decreased whilst emissions from private motoring increased. The decline in heating emissions can be attributed to more efficient central heating systems and increased insulation in modern homes, coupled with milder winters. The increase in private motoring emissions can be related to the increase in travel by car which has been partly offset by the introduction of more fuel-efficient vehicles.
Over the same period, household final consumption expenditure (HHFCE)2, which measures total spending by households, when adjusted for the effects of price inflation, increased by 50 per cent whereas total CO2 emissions increased by 20 per cent. Between 2008 and 2009 HHFCE decreased by 2 per cent, while the carbon dioxide footprint declined by 9 per cent.
Greenhouse Gas emissions associated with UK consumption
CO2 is the main greenhouse gas, accounting for about 77 per cent of total UK consumption greenhouse gas emissions in 2009. The new research indicates that UK’s total carbon footprint, including the other greenhouse gases3 has increased by about 12 per cent between 1990 and 2009. These estimates are less robust than estimates for CO2 only, largely because of inherent uncertainties in the estimation of non-CO2 emissions.
Figure 3 Greenhouse gas emissions associated with UK consumption 1990 to 2009
Figure 3 shows how the proportion of total GHG emissions that arose from the production of imports increased from a third in 1990 to a half of total GHG emissions in 2009. In 2009
GHG emissions associated with imported goods were estimated at 477 million tonnes CO2
equivalent4.
Background to the research
University of Leeds has been contracted for five years to undertake the work on behalf of Defra. The project updates previous work carried out by the Stockholm Environment Institute (SEI) published by Defra in 2008. It uses a multi-region input-output (MRIO) model, which the SEI has developed, to link the flows of goods and services described in monetary terms, with the emissions generated in the process of production. In brief, this is a sophisticated computer model that can assimilate data on emissions and product flows
from different countries and years in different classifications and valuations, dealing with the data gaps and reconciling inconsistencies.
The methods and data sources used in this research remain consistent with those used in the previously published results that are documented in Wiedmann et al (2008). However, due to a change in the Standard Industrial Classification (SIC) used in some of the source data, additional effort has been needed to re-allocate estimates from the more recent classification covering 110 sectors to the previous coverage of 123 sectors. A conversion of recent time series data to the later format based on SIC 2007 is planned for when sufficient source data becomes available.
Revisions to the data since first release
Since the first research was published in 2008, the model has been further refined by CenSA. The data has been expanded, from solely covering CO2 to covering all greenhouse gases, and now encompasses a longer time series, from 1990 to 2009. For most years the result of these refinements has made little difference to the totals – increasing or decreasing them by less than 1 per cent. The overall trend remains the same.
Greenhouse gas emissions uncertainty
Defra published research on the uncertainty in the estimates as part of the previous report on consumption-based CO2 emissions between 1992 and 2004. The research showed that the relative standard error for total CO2 consumption emissions in any one year lies within the range of 3.3 per cent for 1994 and 5.5 per cent for 2004. It was therefore possible to conclude that the estimated increase in total consumption-based emissions over the period was statistically significant. Since then there have been a number of improvements in the model, with more up-to-date and reliable financial data, which should have reduced the range of errors for the more recent years. However, the uncertainty relating to the changes in the UK’s greenhouse gas footprint has not yet been researched and the estimates must therefore be treated with greater caution.
Relationship with other measures of GHG emissions
The UK’s carbon footprint is measured in different ways for different purposes. Each basis of measurement is published by the government. The different bases should be viewed as complementary ways of accounting for carbon emissions.
Territorial basis
Emission estimates are based on the UK greenhouse gas inventory and published by the Department for Energy and Climate Change (DECC) – this is used as the basis for our reporting to the EC and United Nations Framework Convention on Climate Change (UNFCCC), and forms the basis for reporting on progress towards our domestic and international emissions reduction targets. The inventory measures emissions on a territorial basis, so only includes emissions which occur within the UK’s borders. GHG emissions emitted in international territory, i.e. international aviation and shipping, are reported as memorandum items.
Production or Residents basis
Emissions estimates as reported in the UK Environmental Accounts, published by the Office for National Statistics (ONS) - these measure GHG emissions on what is referred to as a “residents” basis, which means that the figures represent emissions produced by UK residents and industry whether in the UK or abroad, but exclude emissions within the UK which can be attributed to overseas residents and businesses. International aviation and shipping emissions are allocated to countries based on the operator of the vessel.
References
Csv dataset
The current research project is ET0101
Wiedmann, T., Wood, R., Lenzen, M., Minx, J., Guan, D. and Barrett, J. (2008) Development of an Embedded Carbon Emissions Indicator – Producing a Time Series of Input-Output Tables and Embedded Carbon Dioxide Emissions for the UK by Using a MRIO Data Optimisation System, Report to the UK Department for Environment, Food and Rural Affairs by Stockholm Environment Institute at the University of York and Centre for Integrated Sustainability Analysis at the University of Sydney, June 2008. Defra, London,
UK
Wiedmann, T., Lenzen, M. and Wood, R. (2008) Uncertainty Analysis of the UK-MRIO Model – Results from a Monte-Carlo Analysis of the UK Multi- Region Input-Output Model (Embedded Emissions Indicator); Report to the UK Department for Environment, Food and Rural Affairs by Stockholm Environment Institute at the University of York and Centre for Integrated Sustainability Analysis at the University of Sydney. Defra, London, UK.
Office for National Statistics Environmental Accounts
DECC UK greenhouse gas inventory
Notes
Whilst the research has not been subject to National Statistics assessment standards, in other respects the analysis has been conducted in line with the National Statistics Code of Practice.