def rechunk_da(da, sample_chunks):
    """

    Args:
        da: xarray DataArray
        sample_chunks:  Chunk size in sample dimensions
    Returns:
        da: xarray DataArray rechunked
    """
    lev_str = [s for s in list(da.coords) if 'lev' in s][0]
    return da.chunk({'sample': sample_chunks, lev_str: da.coords[lev_str].size})