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/1225#issuecomment-326138431,https://api.github.com/repos/pydata/xarray/issues/1225,326138431,MDEyOklzc3VlQ29tbWVudDMyNjEzODQzMQ==,2443309,2017-08-30T22:36:14Z,2017-08-30T22:36:14Z,MEMBER,"@tbohn - What is happening here is that xarray is storing the netCDF4 chunk size from the input file. For the `LAI` variable in your example, that is`LAI:_ChunkSizes = 19, 1, 160, 160 ;` (you can see this with `ncdump -h -s filename.nc`). ```shell $ ncdump -s -h veg_hist.0_10n.90_80w.2000_2016.mode_PFT.5dates.nc netcdf veg_hist.0_10n.90_80w.2000_2016.mode_PFT.5dates { dimensions: veg_class = 19 ; lat = 160 ; lon = 160 ; time = UNLIMITED ; // (5 currently) variables: float Cv(veg_class, lat, lon) ; Cv:_FillValue = -1.f ; Cv:units = ""-"" ; Cv:longname = ""Area Fraction"" ; Cv:missing_value = -1.f ; Cv:_Storage = ""contiguous"" ; Cv:_Endianness = ""little"" ; float LAI(veg_class, time, lat, lon) ; LAI:_FillValue = -1.f ; LAI:units = ""m2/m2"" ; LAI:longname = ""Leaf Area Index"" ; LAI:missing_value = -1.f ; LAI:_Storage = ""chunked"" ; LAI:_ChunkSizes = 19, 1, 160, 160 ; LAI:_Endianness = ""little"" ; ... ``` Those integers correspond to the dimensions from LAI. When you slice your dataset, you end up with lat/lon dimensions that are now smaller than the `_ChunkSizes`. When writing this back to netCDF, xarray is still trying to use the original `encoding` attribute. The logical fix is to validate this encoding attribute and either 1) throw an informative error if something isn't going to work, or 2) change the `ChunkSizes`.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,202964277