html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/2921#issuecomment-492713273,https://api.github.com/repos/pydata/xarray/issues/2921,492713273,MDEyOklzc3VlQ29tbWVudDQ5MjcxMzI3Mw==,10194086,2019-05-15T15:52:12Z,2019-05-15T15:52:12Z,MEMBER,"Today @lukasbrunner and me ran into this problem. Opening an mfdataset and saving `to_netcdf`led to the following units for `time` and `time_units`:

    time_bnds:units = ""days since 1850-01-01"" ;
    time:units = ""days since 2000-01-01"" ;

Opening the dataset in `xarray` works fine, but `ncdump` and `ncview` use the units from `time` for `time_bnds`. Thus if I do

    ncdump -tv time_bnds test.nc 

the first date is `'2150-01-01'` (instead of `'2000-01-01'`) - very confusing. (`panoply` shows the correct `time_bnds`).

## Workaround

``` python
import xarray as xr
filenames = ['file1.nc', 'file2.nc']

ds = xr.open_mfdataset(fNs)
ds.load()

# make sure the encoding is really empty
assert not ds.time.encoding

# assign encoding, such that they are equal
ds.time.encoding.update(ds.time_bnds.encoding)

# save
ds.to_netcdf('~/F/test.nc')

```

Btw. thanks to @klindsay28 for the nice error report.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,437418525