Issues loading ACCESS-OM2-01 data from cycle 4

Technical
3

By adding a few arguments to skip the coordinate verification, this was relatively fast for me (on a login node):

In [42]: %time sis = cc.querying.getvar(
                       "01deg_jra55v140_iaf_cycle4", "aice", s,
                       start_time="1968", compat="override", coords="minimal"
                     )    
CPU times: user 2min 45s, sys: 1min 40s, total: 4min 26s
Wall time: 2min 54s

The long sys time indicates that it spent a long time doing IO, probably because it’s reading 4x2D grids out of every file, and then comparing them all. Maybe this doesn’t come up as badly for the ocean data because it’s not output on a curvilinear grid?

This was brought up before:

With the suggested fix being to use decode_coords=False, as demonstrated in the ice plotting recipe. This gives me very similar timing to above:

In [61]: %time sis = cc.querying.getvar(
                       "01deg_jra55v140_iaf_cycle4", "aice", s,
                       start_time="1968", decode_coords=False
                     )
CPU times: user 2min 39s, sys: 1min 31s, total: 4min 11s
Wall time: 2min 34s

The difference between the two methods is that the first one will give you TLON, TLAT, ULON, ULAT (in addition to time) as coordinates on the resulting DataArray; whereas the second one will only give you a time coordinate – the spatial dimensions just have integer indices.

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