Assessing land ‐ use change in Ireland using a high resolution spatial database: The potential of the Land ‐ Parcel Identification System (LPIS) Jesko Zimmermann 1, *, Phillip O’Brien 2, Stuart Green 3, Ainhoa Gonzales del Campo 1,4, Michael B. Jones 1 and Jane Stout 1,4 1 School of Natural Sciences, Trinity College Dublin 2 Climate Change Unit, EPA, Richview, Dublin 3 Spatial Analysis Unit, Teagasc, Ashtown 4 Trinity Centre for Biodiversity Research, Trinity College Dublin Background The role of vegetation cover and soil in the carbon cycle is well understood. Global emissions have been estimated to be around Gt C yr -1 ( ), with a long-term loss of 124Pg C to the atmosphere. Major sources of emission are land-use change from forestry to agriculture and form grassland to cropland., though reversing the processes can foster carbon sequestration. Therefore, land-use and land-use change related greenhouse gas dynamics are covered by article 3.4 in the Kyoto protocol. Figure 1: Land-use dependency of greenhouse gas dynamics. Dynamics in grassland are strongly depending on land-use history. (Image from Google Earth) The land-parcel identification system Spatial database originally created to help authorities and farmers with single farm payment scheme. Spatially explicit information on land-use for each parcel allows for: Including spatial context into grassland classification, adding auxiliary information. Allows tracking change of single parcels through time. Limitations: LPIS was designed for different purpose, therefore a number of limitations exist: Parcels duplication (e.g. commonage). Ambiguous land-use classification. Changes of parcel outlines through time. No unique land-parcel identification codes for temporal tracking. Figure 2: Image of land-parcels as present in the land- parcel identification system (Year 2012). Figure 3: Land-use categories for the Republic of Ireland (2012 data). Figure 4: Amount of land-use changes in stable parcels between 2000 and Adapting LPIS Raw LPIS data Manual removal of large faulty parcels Removal of duplication parcels Assignment of land-use classes Assignment of unique IDs Suitable for reading out land-use and land-use change Conclusions LPIS has a strong potential for assessing land-use and land-use change with regards to greenhouse gas dynamics, as it allows for spatial tracking of single land-parcels, allowing to overlay auxiliary data, and land-use change tracking. However it requires a number of adaptations to be suitable for this purpose. Furthermore, not all land- use classes within the dataset are suitable (e.g. forestry which does not comply for EU subsides and is therefore only sparsely reported in LPIS). The challenge Currently land-use and land-use change in Ireland are estimated from national statistical data provided by the Central Statistics Office (CSO). Data only offers absolute areas and is not spatially explicit. This leads to a number of limitations: Not accounting for management practices No inclusion of spatially explicit auxiliary data (e.g. soil, climate) Inaccuracy due to assumptions when modelling land-use change from changes in absolute areas.