I'm working with Corine Land Cover Accounting Layers files called "CLC2018ACC_V2018_20.tif.ovr" and "CLC2000ACC_V2018_20.tif.ovr". My goal is to get both qualitative and quantitative informations on the expansion of the forest cover in europe to propose those areas (where the forest is naturally coming back) as a potential object for passive rewilding project. I imported the first file in this way:

clc00 <- raster("CLC2000ACC_V2018_20.tif.ovr")

and then I plotted it with:`


the output is a map of Europe with values between 0 and more than 8000. How can I extract only the forest values? These should be the codes of the different land cover types: https://image.discomap.eea.europa.eu/arcgis/rest/services/Corine/CLC1990_WM/MapServer/legend

  • When I get downloads from the Copernicus Land Monitoring Service the filenames all start like "U2006_CLC2000_V2020_20u1" which is similar but not the same as yours, but my data range is 0 to 255 which ties with the land cover class values. land.copernicus.eu/pan-european/corine-land-cover pick a year, see map, click "Download" get zip, unzip to get another zip, unzip to get DATA,Documents,Legend,Metadata folders. Are we on the same data?
    – Spacedman
    Commented Jan 4, 2022 at 16:25
  • eea.europa.eu/data-and-maps/data/…, here you have my data. I downloaded "CLC2000 Accounting Layer " file and "CLC2018 Accounting Layer" file. Commented Jan 4, 2022 at 16:26
  • I noticed the same thing too. I don't know why the Corine Land Cover Accounting Layers files have different values range! Anyway, these are the right data to use if you want to compare CLC Changes between non-consecutive inventories as the user manual states: land.copernicus.eu/user-corner/technical-library/…. Commented Jan 4, 2022 at 16:32

1 Answer 1



clc00 <- raster("CLC2000ACC_V2018_20.tif.ovr")

is reading the overlay file. You don't want to do that. Read the tif:

> clc = raster("./CLC2000ACC_V2018_20.tif")
Warning message:
In showSRID(SRS_string, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum European Terrestrial Reference System 1989 in Proj4 definition
> clc
class      : RasterLayer 
dimensions : 46000, 65000, 2.99e+09  (nrow, ncol, ncell)
resolution : 100, 100  (x, y)
extent     : 9e+05, 7400000, 9e+05, 5500000  (xmin, xmax, ymin, ymax)
crs        : +proj=laea +lat_0=52 +lon_0=10 +x_0=4321000 +y_0=3210000 +ellps=GRS80 +units=m +no_defs 
source     : CLC2000ACC_V2018_20.tif 
names      : CLC2000ACC_V2018_20 
values     : 111, 999  (min, max)
attributes :
        ID  COUNT CLC_CODE              LABEL1       LABEL2
 from: 111 777883      111 Artificial surfaces Urban fabric
  to : 999  40471      999        999 (Nodata) 999 (Nodata)
                  LABEL3   R   G   B      RED GREEN     BLUE
 Continuous urban fabric 230   0  77 0.901961     0 0.301961
            999 (Nodata) 255 255 255 1.000000     1 1.000000

These values are from 111 to 999 and correspond to the land classes.

You can get the value metadata using levels:

> levels(clc)
    ID     COUNT CLC_CODE                        LABEL1
1  111    777883      111           Artificial surfaces
2  112  16528943      112           Artificial surfaces
3  121   2782230      121           Artificial surfaces
[etc etc etc]

The raster package isn't brilliant for categorical raster data, so you might consider switching to the terra package, which might be better? Not sure...

  • Thank you very much! Now I'm trying to list the two files from 2000 and 2018 in this way: rlist <- list.files(pattern="") but I don't know what to put inside the quotation marks. If I'd manage to do it then my idea would be: import <- lapply(rlist,raster) clc0018 <- stack(import) and finally plot(clc0018). Any guess? thanks a lot. Commented Jan 5, 2022 at 12:04
  • basically my problem is that I don't know which file is the right one to coose.. Commented Jan 5, 2022 at 12:14
  • Read the files that end in .tif - they are the true source of the raster data. The .ovr files are "overviews", basically low-resolution approximations for quick rendering to save software having to load a massive .tif if all you want is a simple view.
    – Spacedman
    Commented Jan 5, 2022 at 13:51
  • Sure, but if I rename the 2 tiff file in order to have a common part like "aaaCLC2000ACC_V2018_20" and "aaaCLC2018ACC_V2018_20" and then rlist <- list.files(pattern="aaa"); import <- lapply(rlist,raster); import the output is: [[1]] class : RasterLayer values : -32768, 32767 (min, max) [[2]] class : RasterLayer values : -32768, 32767 (min, max). that is, again the wrong values files! Commented Jan 5, 2022 at 15:27
  • 1
    yes I do. Should I just ask a new question? Commented Jan 5, 2022 at 15:31

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.