Transfer feature details from WMS to raster file

Question

I need to export a WMS Map in a raster (QGIS) as I would like to do a zonal statistic after I need the WMS raster values. I can see them in the Identify results panel. The WMS has single Band color data but after exporting it, it has 4 bands with only the colour values, not the feature values. (see picture) Is there a possibility in exporting the WMS to a raster and keeping the values? I always tried it with a tiff. Is another format better? Does anyone know how to export only one band? this might help already.

If anyone knows how to do it in ArcGIS it would help too. This are the feature details of the WMS map These are my export settings these are the feature details of the exported Tiff with 4 bands

The WMS map Bullerkartan 2012, alla källor: (contextualWMSLegend=0&crs=EPSG:4326&dpiMode=7&featureCount=10&format=image/png&layers=mftemp:luftkvalitet-2015-no2ytor&styles&url=http://kartor.miljo.stockholm.se/geoserver/wms?layers%3Dmfraster:bullerkartan-2003-allakallor)

Answer 1

Is there a possibility in exporting the WMS to a raster and keeping the values?

No, A WMS GetMap operation doesn't give access to the raw data, you only get a representation of the underlying data.

You would need a WCS or WFS to get at the raw data, and luckily in this case the service provider gives you a WFS, check the feature type information:

http://kartor.miljo.stockholm.se/geoserver/ows?service=WFS&request=DescribeFeatureType&typename=mftemp:luftkvalitet-2015-no2ytor&version=1.1.0