[MITgcm-support] what happens when run is shorter than diagnostic averaging frequency

[Daniel Goldberg]

Thanks Martin.

Dan
________________________________
From: MITgcm-support <mitgcm-support-bounces at mitgcm.org> on behalf of Martin Losch <Martin.Losch at awi.de>
Sent: Wednesday, August 2, 2023 11:01
To: MITgcm Support <mitgcm-support at mitgcm.org>
Subject: Re: [MITgcm-support] what happens when run is shorter than diagnostic averaging frequency

This email was sent to you by someone outside the University.
You should only click on links or attachments if you are certain that the email is genuine and the content is safe.
Hi Dan,
I am not sure what the diagnostics package does in this case, but you can write pickup files with the diagnostics package that avoid this problem. These the relevant runtime parameters for data.diagnostics (from diagnostics_readparms.F):

     &     diag_pickup_read,     diag_pickup_write,
     &     diag_pickup_read_mnc, diag_pickup_write_mnc,

Martin

On 2. Aug 2023, at 07:59, Daniel Goldberg <Dan.Goldberg at ed.ac.uk> wrote:

Hello All

This might be a very basic question but i can't figure it out from looking at the code.

I am using the frequency() parameter in data.diagnostics with a value > 0, and NOT using timephase() or averagingFreq(). For experiment-specific reasons I am restarting from a pickup on a frequency shorter than the diagnostic frequency, i.e.

frequency(1) = 2592000

but the length of each run i.e. nTimesteps * deltaT = 432000.

So, every 6th run, a diagnostics file is written, for a run that is 5 days long, with an averaging period of 30 days (Im using a model calendar if it matters). I am just wondering what diagnostics will do in this case. When a diagnostics file is written, will it average only over the last 5 days? Will it do so, but give a value that is 6 times too small?

Many thanks! As I said, apologies if this should be obvious from the docs!

dan

--
Daniel Goldberg, PhD (he/him)
Reader in Glaciology
School of Geosciences, University of Edinburgh
Geography Building, Drummond Street, Edinburgh EH8 9XP

Please note I am not working Mondays during June/July/August 2023 due to childcare responsibility.

The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336. _______________________________________________
MITgcm-support mailing list
MITgcm-support at mitgcm.org<mailto:MITgcm-support at mitgcm.org>
http://mailman.mitgcm.org/mailman/listinfo/mitgcm-support

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.mitgcm.org/pipermail/mitgcm-support/attachments/20230802/61e5e0c4/attachment.html>