Greenhouse Gas Emissions Estimates for England s National Parks

Transcription

1 Greenhouse Gas Emissions Estimates for England s National Parks English National Park Authorities Association November 2010

2 Greenhouse Gas Emissions Estimates for England s National Parks WGB Environment for English National Park Authorities Association Commissioned by Yorkshire Dales National Park Authority on behalf of the English National Park Authorities Association Final Report November 2010 This report covers greenhouse gas emissions for all greenhouse gases other than Carbon Dioxide for all English National Parks. Contacts Gary Smith Head of Conservation & Policy Yorkshire Dales National Park Authority Gary.Smith@yorkshiredales.org.uk Bill Butcher WGB Environment bill.butcher@wgbenvironment.net Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 2 of 9

3 1.0 Introduction 1.1 Greenhouse gas emission estimates for gases other than carbon dioxide are presented for nine of the ten English National Parks. 1.2 This analysis complements an earlier report that estimated carbon dioxide emissions and removals for the National Parks (AEAT, 2009). Emissions for Exmoor National Park calculated as part of a wider carbon neutral analysis (Butcher and Stephenson, 2009) are included here for completeness. 1.3 England s ten National Parks cover 9.3% of the country s land area. National Park Authorities (NPAs) are the bodies charged with looking after these areas. Each NPA operates as an independent local authority, but the NPAs also work together through the English National Park Authorities Association (ENPAA). The NPAs require information on greenhouse gas emissions within the boundary of National Parks in order to help define and prioritise their climate change work. 1.4 The Authorities for National Parks included in this report are: Broads Authority, Dartmoor NPA, Exmoor NPA, Lake District NPA, New Forest NPA, Northumberland NPA, North York Moors NPA, Peak District NPA, South Downs NPA, Yorkshire Dales NPA. 2.0 Methodology 2.1 The National Atmospheric Emissions Inventory (NAEI) was used as the data source for greenhouse gas (GHG) emissions. This provides annual data for emissions of all six principal GHGs, with carbon dioxide, methane (CH 4 ) and nitrous oxide (N 2 0) data presented on a 1km square basis for each local authority area. 2.2 The latest data currently available is for the year Emissions in the NAEI inventory are broken down into eleven UNECE 1 sectors. 2.4 The NAEI is compiled for Defra annually using a wide range of data analysis and modelling techniques (AEAT, 2008). 2.5 Boundaries of National Parks were downloaded for this project from the Natural England website. These are understood to be the latest available GIS vector boundaries, with the latest amendment dated August NAEI files for methane and nitrous oxide for all local authorities intersecting with the nine National Parks were downloaded from the NAEI website. 2.7 These files were compiled into composite methane and nitrous oxide files using Microsoft Excel. 2.8 These composite files were then opened in MapInfo GIS and made spatial using the centre point 1km attributes. 2.9 A visual check was made at this stage to ensure that all relevant local authority data had been included. 1 United Nations Economic Commission for Europe Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 3 of 9

4 2.10 The requirement of the project was to generate National Park specific emissions data. National Park boundaries cut across one kilometre squares; therefore a method is needed to estimate with maximum accuracy the portion of the emissions in boundary squares that should be included in the National Park estimate To achieve this a 1km grid was generated for the whole of England. A 1km buffer was then generated around each National Park, and a table generated of all 1km squares that intersect with the National Parks including their buffers Using a National Park area attribute, each square wholly within a park was allocated 100 hectares (the area of a 1km square). Remaining grid squares, the boundary squares, were then cut to the National Park boundary, and the area of each calculated to populate the National Park area attribute This number, the National Park area attribute, was then used to adjust the emissions data for boundary squares e.g. a grid square with 56 hectares within the park was allocated 56% of the inventory emissions for that square The emissions data files were then joined to the grid files, linking the emissions data to the grid squares After adding the National Park name, the data was exported to Excel The emissions data is in tonnes of each greenhouse gas and needs to be converted to carbon dioxide equivalent to provide meaningful data that allows comparison across GHGs. The standard conversion factors of 21 for methane and 310 for nitrous oxide, as used internationally, were used for this purpose (Choudrie et al. 2008) Data analysis in Excel provided the total emissions in CO 2 e for methane and nitrous oxide in each National Park The eleven principal UNECE sectors were combined to six sectors as shown in Table 1 for presentation in this report. Combined sector used in this report UNECE sector 01. Energy Production and Transformation 03. Industrial Combustion Industry 04. Industrial Processes 05. Production and Distribution of Fossil Fuels 06. Solvent Use 02. Commercial, Institutional and Residential Domestic Combustion 07. Road Transport Transport 08. Other Transport Nature 11. Nature Agriculture 10. Agriculture Waste 09. Waste Treatment and Disposal Table 1 Aggregation of UNECE sectors Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 4 of 9

5 2.19 Data for the UNECE sector code 2, Commercial, Institutional and Residential Combustion, here summarised as Domestic, is not available spatially broken down into more precise categories. It actually comprises four NAEI detailed source sector categories. At UK level, the Domestic Consumption detailed sector category accounts for 87% of methane emissions and 82% of nitrous oxide emissions of the combined sector emissions. The other three detailed sectors are Miscellaneous industrial/commercial combustion, Public sector combustion and Agriculture stationary combustion UNECE sector 11, labelled Nature in the NAEI inventory actually comprises five detailed sectors, all of which relate to accidental fires (forests, straw, vegetation, dwellings and other buildings). The state of research into LULUCF (Land Use, Land Use Change and Forestry) emissions and removals for methane and nitrous oxide is not well enough advanced for estimates to be included in the UK s international submission of greenhouse gases, and therefore no LULUCF figures are included in this report Although the data are not strictly comparable, Agriculture and LULUCF data can be summed for carbon dioxide, methane and nitrous oxide, using carbon dioxide equivalent units, under the simplified heading Land Use The remaining GHGs are the F-gases, HFC, PFCs and SF 6. Emissions for these gases are not mapped within the NAEI and therefore it is not possible to allocate emissions to National Park boundaries The overall contribution of the F-gases to the total GHGs emissions in the UK is very small. In 2006 HFCs contributed 1.4% of CO 2 e, PFCs 0.04% and SF %. (Choudrie et al. 2008) Since the sources of the F-gases are predominantly industrial, and industry is not spatially evenly distributed and infrequent within National Parks, it is highly probable that the relative contributions of the F-gases to overall National Park emissions are well below the UK average, which is itself very small. 3.0 Data Accuracy 3.1 The data presented is believed to be accurate within the limitations of the source data. AEAT, 2008, should be consulted for full description of uncertainties around modelling of elements within the inventory. 3.2 The emissions relating to boundary grid squares are allocated to the National Park in proportion of the area of the grid square falling within the Park. This assumes that the emission sources are equally distributed inside and outside the park boundary for these squares. While this is likely to approximate to reality, there may be a slight overestimate of National Park emissions, as boundaries are sometimes drawn to exclude high population areas, industrial sites and waste disposal sites, where emissions are likely to be higher. Emissions in boundary squares represent around 15% of the total for N 2 O and 17% of the total for CH 4. This potential uncertainty may therefore represent an overestimate of a few per centage points. 3.3 Although use of the more precise sector categories would give greater precision (e.g. agricultural fuel is included within industry rather than agriculture) the spatial data is available only at principal sector level. Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 5 of 9

6 3.4 As noted in 2.20 no LULUCF figures for methane or nitrous oxide are currently available. Local research in the Norfolk Broads has suggested that natural sources of nitrous oxide emissions from wetlands and woodland may be significant (G Smith, pers. comm.). 4.0 Results 4.1 Emission estimates for N 2 O and CH 4 for the nine National Parks in 2008 are shown in Table emissions in tonnes CO2e National Park Nitrous Oxide Methane Broads Dartmoor Exmoor Lake District New Forest North York Moors Northumberland Peak District South Downs Yorkshire Dales Total Table 2 Emission estimates for N 2 O and CH Emission estimates by sector are shown for N 2 O in Table 3 and for CH 4 in Table 4. UNECE Sector Groups National Park Industry Domestic Transport Waste Nature Agriculture Broads Dartmoor Exmoor Lake District New Forest North York Moors Northumberland Peak District South Downs Yorkshire Dales Total Table 3 Emission estimates by sector for N 2 O Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 6 of 9

7 Agriculture Waste Transport Industry Domestic Figure 1 Total N 2 O emission estimates by sector, nine English National Parks 4.3 The principal agricultural source of nitrous oxide emissions is in the breakdown of artificial fertilisers (AEAT,2008). Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 7 of 9

8 UNECE Sector Groups National Park Industry Domestic Transport Waste Nature Agriculture Broads Dartmoor Exmoor Lake District New Forest North York Moors Northumberland Peak District South Downs Yorkshire Dales Total Table 4 Emission estimates by sector for CH 4 Agriculture Waste Industry Domestic Transport Nature Figure 2 Total CH 4 emission estimates by sector, nine English National Parks 4.4 The principal agricultural source of methane emissions is enteric fermentation. Methane emissions from waste disposal and treatment arises primarily from breakdown of organic matter in landfill sites (AEAT,2008). Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 8 of 9

9 4.5 An example of the spatial distribution of emissions across a National Park is shown in Figure 3. Nitrous Oxide Emission Estimates Yorkshire Dales National Park (tonnes CO2e/km2) 2,000 to 10, to 2, to to to to to to to to to 40 0 to 20 WGB Environment for English National Park Authorities, kilometres Figure 3 Emission estimates for N 2 O across the Yorkshire Dales National Park, References AEAT (2008) NAEI UK Emission Mapping Methodology Defra. AEAT (2009) Carbon Dioxide Emission estimates for the England National Parks. Unpublished report for the English National Park Authorities Association. Butcher W and Stephenson W (2009) A Carbon Neutral Strategy and Programme for the Exmoor National Park. Climate Action West for the Exmoor National Park Authority. Choudrie SL, Jackson J, Watterson JD, Murrells T, Passant N, Thomson A, Cardenas L, Leech A, Mobbs DC, Thistlethwaite G (2008) UK Greenhouse Gas Inventory, 1990 to Annual Report for submission under the Framework Convention on Climate Change. Defra. NAEI website. Natural England website. Thomson A.M., D.C. Mobbs, R. Milne, U. Skiba, A. Clark, P.E. Levy, N. Ostle, S.K. Jones, M.F. Billett and M. van Oijen (2008) Inventory and projections of UK emissions by sources and removals by sinks due to land use, and use change and forestry. Annual Report to Defra, July Centre for Ecology and Hydrology, Edinburgh. Final Report November 2010, WGB Environment for English National Park Authorities Association, Page 9 of 9