9 - use case: monthy gridded data

From the monthly folder at gridbase, we want to download .asc.gz files for selected years and open them in R for further processing.

Note: I’m using quiet=TRUE to keep this vignette concise. In real life, the messages may be important to you…

For .asc.gz files, readDWD calls readDWD.raster. This runs faster if called a second time due to skip=TRUE in gunzip.
Now we can project and visualize with:

For further processing, we can create a raster stack from the list, which e.g. enables fast and easy indexing.

A few projection references:

The Beschreibung file leads to https://spatialreference.org/ref/epsg/31467/ from which the proj4 format is used internally in projectRasterDWD, currently at line 54.
Bettina Ohse reported using dwd.projection <- '+init=epsg:31467' instead.