The CLC2012 land mask is a dataset derived from CLC2012 intended to be used as a reference dataset for data harmonisation within the EEA. It is a mask where all pixels with any valid land cover class value in CLC2012, except for class 523 - Sea and ocean, get a value of "1". The rest of pixels get a "0". In other words, land areas with CLC2012 data are identified with the value "1", whereas sea areas and areas with no CLC2012 data available get a value of "0".

The LEAC mask at 1 km x 1 km is a dataset derived from CLC2012 used as the reference mask for accounting purposes within the EEA. It is a mask where all 1 km x 1 km cells (in line with the European reference Grid) with any valid land cover class value in CLC2012, except for class 523 - Sea and ocean, get a value of "1". The rest of pixels get a "0". In other words, land areas with CLC2012 data are identified with the value "1", whereas sea areas and areas with no CLC2012 data available get a value of "0".