How to make a new raster out of two other rasters [duplicate]

Question

I have two raster images, one is the Corine Land Cover for the year 2000 and another one which is the anthropogenic effect on land. The first image reclassified in 9 categories:

• Artificial surfaces
• Agricultural areas
• Forests
• Scrub and/or herbaceous vegetation associations
• Open spaces with little or no vegetation
• Inland wetlands
• Maritime wetlands
• Inland waters
• Marine waters

And the second image has seven categories:

• Closed τree or shrub vegetation, canopy cover > 70%
• Open tree or shrub vegetation, canopy cover > 40-70%
• Scattered tree or shrub vegetation, canopy cover <40%
• Bare of any vegetation area
• Αbandoned fields, grasslands and scrubland zones of deciduous oaks and fir
• Βrushwood
• Cultivated areas

What i want to do is to built a new raster with the information from these two rasters. For example i want to keep the information from "waters" from corine, and combine the information for Forests from corine and from the other raster the "Closed tree or shrub vegetation".

I need you help.

Answer 1

Try reclassifying the corine raster in multiples of 10 eg Artificial surface = 10 Agricultural = 20 Forests = 30 etc

Then reclassify the second image using values from 1 to 7 (1 for closed canopy, 2 for open etc)

Sum the resultant reclassified rasters together you should get a raster with the values combined so for instance corine forest that is closed canopy from your second image should all score 31.

Definitely worth sense checking your results though as the datasets may be at different resolutions so you may end up with some daft new categories - closed canopy inland waters!