eTheses Repository - University of Birmingham

3.5 Data sources
This section describes the data sources which were used for the construction of the model
domains, the initialisation of the model runs, and the validation of the model results.
3.5.1 Land cover data
The CEH Land Cover Map 2000 (LCM2000) was used to derive the land cover
classification for the model domain. The LCM2000 is a 1 km x 1 km raster dataset
covering Great Britain which was created from a 25 m x 25 m pixel resolution dataset
within a 1 km x 1 km grid. The dataset is a digital map made by analysis of spectral
reflectance data from Earth observation satellites. LMC2000 has two urban land use
classes, representing continuous urban land cover and discontinuous suburban land cover.
These were used in order to classify the urban land cover into two BEP urban classes with
characteristics representing urban and suburban land cover. All large areas of vegetation in
LMC2000 (>0.5 ha) are distinguished by the appropriate land cover class, and these will be
likewise represented in METRAS by the most appropriate land cover class.
Since LCM2000 has 27 land cover classes, compared to the 10 classes used in the
METRAS model, the classes must be summarised into the METRAS classes. A
FORTRAN programme was written to convert the LCM2000 data set into the 10
METRAS land cover classes. On the basis of the description of the LCM2000 classes
provided, the CEH land cover percentages were aggregated into the 10 METRAS land
cover classes using summary in Table 3.3.
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