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Urban Land Use: lessons from the Urban Atlas. Lewis Dijkstra Deputy Head of the Analysis Unit European Commission – DG Regional Policy Lewis.Dijkstra@ec.europa.eu. Overview. New grid based definitions Urban-rural regional typology: Urban clusters Degree of urbanisation
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Urban Land Use: lessons from the Urban Atlas Lewis Dijkstra Deputy Head of the Analysis Unit European Commission – DG Regional Policy Lewis.Dijkstra@ec.europa.eu
Overview • New grid based definitions • Urban-rural regional typology: Urban clusters • Degree of urbanisation • Cities and hinterland: High-density clusters and commuting zones • Measuring urban land use • CORINE • Soil sealing • Urban Atlas
A new urban-rural regional typology • Classifying EU NUTS3 regions • A variant of the OECD methodology • Aiming to provide a consistent basis for describing urban, intermediate and rural regions in various Commission reports and publications • Developed by: • DG Agriculture and Rural Development • DG Regional Policy • Eurostat • DG Joint Research Centre
Why a new typology? • Distortions using the OECD methodology at NUTS3 level • Large variation in area of local administrative units (LAU2) • Large variation in area of NUTS3 regions • Some city centres separated from surroundings, at NUTS3 level
The new typology: local level • Units: 1 km² grid cells • Population grid: registered population when available, otherwise disaggregation grid (JRC) • Identify population living in urban areas: • Selection of grid cells with density > 300 inh./km² • Only groups of grid cells, representing a total population of > 5000 inhabitants • Contiguity is evaluated including diagonals
What is degree of urbanisation? Classification of all LAU2s into three categories: Thinly populated Intermediate density Densely populated It is used primarily in the Labour Force Survey (LFS), but also in other surveys such as Survey on Income and Living Conditions (SILC) and IT It is based on LAU2 density and contiguity In use for 20 years
Why a revision? Distortions due to the large variation in area of local administrative units (LAU2) Revised urban-rural typology is based on a grid based definition of rural areas which is more reliable than OECD or LFS approach Harmonising spatial concepts Rural (OECD) and thinly populated areas (LFS) Densely populated areas (LFS) and cities (UA)
New Proposal: Harmonised definition based on population grid
Definitions Rural grid cells = cells outside urban clusters Urban clusters = contiguous (including diagonals) cells with a density of at least 300 inhab/km2 and a minimum of 5 000 inhabitants High-density clusters = contiguous (without diagonals and with gap filling) cells with a density of at least 1500 inhab/km2and a minimum of 50 000 inhabitants
Population grid Units: 1 km² grid cells (future reference for all population grids) Registered population in NO, CH, HR, AT, FI, SE, DK and NL Elsewhere disaggregation grid v5 (JRC) FR is creating a real 1 km2 population grid
Why a new definition? • No harmonised European definition of a city and its functional area existed • Use the same criteria as the degree of urbanisation • Uses commuting analysis to define commuting zone • Consider poly-centricity by checking for connected centres
City definition • A city consists of one or more municipalities (local administrative unit level 2 LAU2). • At least half of the city residents live in an urban centre (i.e. a cluster of high-density grid cells with the gaps filled) • An urban centre has at least 50 000 inhabitants.
Hinterland definition • If 15% of employed persons living in one city work in another city, these cities are combined into a single destination (polycentric) • All municipalities with at least 15% of their employed residents working in a city are identified • Municipalities surrounded by a single functional area are included and non-contiguous municipalities are dropped
Goal and obstacles • Accurately measure urban land use, especially at the urban fringe • CORINE is designed to mainly measure agricultural uses, coarse resolution and does not identify low-density developed (i.e. below 50% of soil sealing) • Soil sealing, high resolution and measures all levels of sealing, but no land use info
The Urban Atlas • Designed to measure urban land use at high resolution and at low levels of soil sealing • Providing harmonised land cover/land use maps according to a common classification • Covering 305 major European agglomerations, based on Urban Audit’s Larger Urban Zones • Imagery reference year: 2006 (+/- 1 year) • Project duration: 2009-2011
Main features • Thematic classes based on CORINE Land Cover nomenclature • But more specific for built-up areas, and less specific outside urban areas • Geometric resolution of 1:10,000 • Minimum mapping unit of 0.25 ha in urban areas, 1 ha in other areas
Production • Mix of automatic classification and photo-interpretation • Various data sources used, depending on thematic classes
Thematic classes • Residential areas: use of soil sealing layer to distinguish between density classes
Thematic classes • Non-residential urban areas • Detailed transport network layer (COTS) • Local maps as auxiliary source of information
Thematic classes • Other classes • Less thematic detail for agricultural, natural and forest areas (and MMU 1 ha)
Dissemination • Georeferenced layers are freely available • Data download: http://www.eea.europa.eu/data-and-maps/data/urban-atlas • Map viewer: http://dataservice.eea.europa.eu/map/UrbanAtlasbeta/
Derived indicators • Can be exploited at the level of Urban Audit units: • Larger Urban Zone (LUZ), kernel, city, sub-city districts (SCD) • Land cover/use surface breakdown • Green urban areas per inhabitant • A sprawl index (ESPON project): www.espon.eu
The future of the Urban Atlas • Repeat Urban Atlas in order to create a detailed dynamic view on urban land cover/use • Coherence with other data collection projects is important • Census 2011 • Urban Audit • Consequences • Define imagery acquisition requirements (2011 +/- year) • Update methodology, including change detection, to be determined • Ensure compatibility with revised Urban Audit following new harmonised definition