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/3819#issuecomment-653237372,https://api.github.com/repos/pydata/xarray/issues/3819,653237372,MDEyOklzc3VlQ29tbWVudDY1MzIzNzM3Mg==,2448579,2020-07-02T22:00:02Z,2020-07-02T22:00:02Z,MEMBER,Please reopen if you have more questions.,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,574015429
https://github.com/pydata/xarray/issues/3819#issuecomment-610077592,https://api.github.com/repos/pydata/xarray/issues/3819,610077592,MDEyOklzc3VlQ29tbWVudDYxMDA3NzU5Mg==,2448579,2020-04-06T22:52:41Z,2020-04-06T22:52:41Z,MEMBER,"There is a subtle error here:

```
>>> grid['sea_surface_temperature'].expand_dims('time', axis=0)
<xarray.DataArray 'sea_surface_temperature' (time: 1, lat: 160, lon: 360)>
array([[[1., 1., 1., ..., 1., 1., 1.],
        [1., 1., 1., ..., 1., 1., 1.],
        [1., 1., 1., ..., 1., 1., 1.],
        ...,
        [1., 1., 1., ..., 1., 1., 1.],
        [1., 1., 1., ..., 1., 1., 1.],
        [1., 1., 1., ..., 1., 1., 1.]]])
Coordinates:
  * lat      (lat) int64 -80 -79 -78 -77 -76 -75 -74 ... 73 74 75 76 77 78 79
  * lon      (lon) int64 -180 -179 -178 -177 -176 -175 ... 175 176 177 178 179
Dimensions without coordinates: time
```

`time` is added as an **unindexed** dimension with no `encoding` or `attrs` dicts. This is because once you pull the DataArray `sea_surface_temperature` out of the dataset; the `time` variable in the dataset is not attached to that DataArray (since it doesn't have a time dimension).

When the expanded dataarray is assigned back to the dataset, we run into #2180

The only solution I could find is 
```
grid[""sea_surface_temperature""] = grid.sea_surface_temperature.expand_dims(""time"", axis=0).assign_coords(time=grid.time)
```","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,574015429
https://github.com/pydata/xarray/issues/3819#issuecomment-594076209,https://api.github.com/repos/pydata/xarray/issues/3819,594076209,MDEyOklzc3VlQ29tbWVudDU5NDA3NjIwOQ==,2448579,2020-03-03T17:40:35Z,2020-03-03T17:40:35Z,MEMBER,"Thanks for the clear reproducible example @jfpiolle. I am marking this as a bug.

Are you up for fixing it?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,574015429