Centre for Landscape and Climate Research
UK Corine Land Cover Map 2012
Heiko Balzter
www.le.ac.uk/clcr
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History of Corine UK• The UK has contributed to all previous CORINE Land Cover (CLC) maps. • Previous CLC projects have adopted a bottom up approach using generalisation of
the national land cover products. • All previous updates of the CLC maps have been carried out by the Natural
Environment Research Council’s (NERC) Centre for Ecology and Hydrology (CEH). • CLC1990 was produced for the UK in two separate administrative units: Great
Britain (England, Scotland and Wales) and Republic of Ireland and Northern Ireland using different methods.
• CLC2000 was produced for the full UK, by semi-automated generalisation of the Land Cover Map 2000.
• CLC2006 was again produced for the full UK by semi-automated generalisation of the Land Cover Map 2007 in Great Britain by 1Spatial and by conventional update of the CLC2000 in Northern Ireland.
• For CLC2012 there is no national UK land cover product, so a visual interpretation approach using satellite imagery has been adopted following the technical guidelines from the European Environment Agency (EEA).
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CLC 2012• CLC2012 has been produced by the University of Leicester (UoL) with
support from Specto Natura Ltd. (SN).• Historically, there has only been limited awareness and use of CLC in UK
government due to the availability of a reasonably contemporaneous national land cover product with superior spatial resolutions and a nomenclature aligned to UK applications.
• However, LCM2007 is now out of date, so more users may turn to CLC2012.
• The production team was:– Prof. Heiko Balzter, Dr. Geoff Smith, Dr. Beth Cole, Dr. Booker Ogutu, Diane Palmer and
Sophie King.
• Training by EEA was received at start of production.
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Problems• Persistent cloud cover led to delays in delivery of HRLs• Also, gaps in GIO data layers had to be filled• Different acquisition dates were mosaicked together, which made
interpretation complicated• Some bugs in the EEA in-house software (Interchange) had to be identified
and fixed• Difficulties in obtaining input data, e.g. LCM2007 from CEH• Staff turnover and time pressure on delivery due to limited resources
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Image2012• Number of available images in
2011, 2012 and 2013 and the Image2012 mosaic.
• Second coverage:
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Training visit outcomes• The training visit report by EEA made the following recommendations:
1. Interpretation should start despite the gaps in IMAGE 2012 data for the UK. Subsequent image acquisition in 2013 will be needed. AWiFS monthly composites were recommended to gap fill, however, these were not available for the UK.
2. Possible changes between arable and pasture land were not possible to check because of the lack of multi-seasonal imagery.
3. Separation of the two grassland types (231-pastures and 321-natural grasslands) must be done on land parcel structure, also the separation of moors and heaths (322) and peatlands (412) requires in-situ data.
4. CLC2006 contains lots of thematic and topological mistakes that need to be mapped as revisions in order to derive real change.
5. Google Earth (GE) imagery was an efficient tool in checking the validity of a CLC2006 polygon and interpreting change. Use of GE data is important because no national orthophotos are available.
6. The use of Coverage -2 data for IMAGE 2012 is recommended when it becomes available for the UK.
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CLC2006
• Corrections, corrections and more corrections…
• UK LCM2007 vector topology was not available to the team
• Polygon boundaries did not match Image2006 interpretation
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Dominant corrections to CLC2006Table 4.2. Dominant corrections made to the CLC2006 revision layer ranked on area. Change code
Description of change Number of polygons
Area (ha)
% of change (area)
322-412 Moors and heathland corrected to peatlands
4212 711475 18.84%
321_412 Natural grasslands corrected to peatlands
3474 370911 9.82%
211_231 Non-irrigated arable land corrected to pastures
10981 273934 7.25%
231_211 Pastures corrected to non-irrigated arable land
11587 272703 7.22%
321_322 Natural grassland corrected to moors and heathland
4469 269480 7.13%
333_412 Sparsely vegetated areas corrected to peatlands
946 169268 4.48%
322_321 Moors and Heathland corrected to natural grasslands
3090 97512 2.58%
523_522 Sea and ocean corrected to estuaries
41 78530 2.08%
333_322 Sparsely vegetated areas corrected to bare rocks
1085 72143 1.91%
321_231 Natural grasslands corrected to pastures
2603 66421 1.76%
243_231
Land principally occupied by agriculture with significant areas of natural vegetation corrected to pastures
786 65201 1.73%
333_321 Sparsely vegetated areas corrected to natural grasslands
940 64569 1.71%
412_322 Peatlands corrected to moors and heathlands
1857 60628 1.61%
231_321 Pastures corrected to natural grasslands
2310 56616 1.50%
312_313 Coniferous forest to mixed forest 1086 49699 1.32%
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Production process• Production units follow Ordnance Survey grid
squares (right)• Mosaicking is required to stitch together the
final CLC map tiles.• Remapping along the edges is necessary to
smooth the polygons.• Slow process due to the database size.
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Change layer 2006-2012
• 9705 polygons of change, representing 167 different change types that cover an area of 225,238 ha (1% of total area of the UK)
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Dominant change typesTable 4.5. Dominant CLC changes between 2006 and 2012.
Change code
Change description No. of poly.
Area (ha)
Area, % of total change
312-324 Clear cutting of coniferous forest 4806 122501.72 54.39%
324-312 Growth/replanting of coniferous forest 1558 46007.48 20.43% 324-324 Technical change – transitional woodland-
shrub 705 6911.37 3.07%
211-131 Arable land to mineral extraction sites 165 3442.48 1.53% 313-324 Clear cutting of mixed forests 255 3189.61 1.42% 133-112 Completion of construction sites to urban
areas. 125 2881.36 1.28%
312-121 Coniferous forests lost to industrial development
65 2861.96 1.27%
211-133 Arable land converted to construction sites 131 2624.56 1.17% 231-131 Pasture land to mineral extraction sites 114 2213.82 0.98% 231-133 Pasture land converted to construction sites 139 2088.32 0.93% 131-231 Mineral extraction sites converted to pasture
land 60 1833.12 0.81%
231-211 Pasture land converted to arable land (intensification of agriculture)
73 1424.39 0.63%
324-313 Growth/replanting of mixed forests 48 1094.47 0.49% 312-312 Technical change – coniferous forest 133 1068.79 0.47% 133-121 Completion of construction sites to industrial
and commercial developments 40 1058.15 0.47%
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Level 2 aggregated change
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Level 1 aggregated change
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Dominant land cover in 2012
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Outlook on Copernicus• Copernicus next generation service framework review• User requirements• Access to Image2012 data stream• Cloud cover makes the case for SAR to augment optical
imaging• Multi-scale land cover mapping?• (Semi-)automatic land cover change detection between CLC?
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Sentinel-1 SAR for land cover
Hybrid level 2/3 CLC classes over Erfurt, Thuringia, Germany