Variable attribues: how to deal with them

[sidekock]

Hi,
I am trying to build a long dataset of satellite observations. As you may know, from time to time new satellites are used so some of the used attributes change. However, if I want to merge these observations in a bigger dataset, xr.combine_by_coords seems to not like that because the attributes are changing. Is it not possible to store a time-specific attribute in xarray (time is one of my coords) ? I understand the assumption that most attributes are not changing but how would I be able to still keep this very useful information?
Kind regards
Simon

[e-marshall]

hi @sidekock , a nice way to store metadata / attribute data that varies along a dimension is as a coordinate variable that exists along those dimension(s).

if you have a dataset with (x,y,time) dimensions, you could have a coordinate variable representing the attribute data that exists only along the time dimension (eg. coordinate variable sensor_name would hold a 1 x len(time) array that contains the sensor name for each element of the time dimension). does this match what you're hoping to do? Feel free to share a minimal reproducible example with more detail on your attribute data as well.

You might also find some useful information here