Negative ozone at top of HadGEM2-A

[iamack]

Hello

In my HadGEM2-A run on HECToR (xfhda) I have selected output of
'ozone MMR after LW', STASH section 2, item 260, on all 38 model theta levels (Charney-Philips grid) at hourly frequency. At the top model level, almost every hourly output has a few quite substantially negative ozone values over Tibet, and the field is generally quite noisy (see attached plot). At the 2nd top level, there are no negative values, but the field remains surprisingly noisy. I would have expected the ozone field at these upper levels to look very similar to the smooth zonal mean field in the ozone ancillary file RSPARC_O3_N96_1990.anc.

Is there a reason I shouldn't be outputting ozone in this way?

Ian

[iamack]

ozone map

[lois]

I am not at all sure about this Ian. Have you emailed your question to Scott Osprey (sosprey@…) and put the question to him?

Lois