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Hi Flynn,
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<div class="">In the past few years we’ve updated and improved the first few tutorials, including expressing the stability criteria more specific to the time-stepping scheme being used (Adam Bashforth II, the model default). The global tutorial has not yet
been updated; presently, we’re working on an improved coarse global setup. The inertial stability criterion in this older tutorial is more general, ie not specific to the ABII scheme, and as such, a bit more lenient.</div>
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<div class="">Best,</div>
<div class="">Jeff</div>
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<div class="">On Mar 20, 2023, at 9:30 AM, Flynn Ames <<a href="mailto:f.ames@pgr.reading.ac.uk" class="">f.ames@pgr.reading.ac.uk</a>> wrote:</div>
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Dear MITgcm community,</div>
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Hello - I have a very quick question regarding stability criterion in the MITgcm tutorial experiments I was wondering if someone could answer?</div>
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In the first three MITgcm tutorials, the stability criterion for inertial oscillations using Adams Bashforth is stated as: f*delta_t > 0.5 for stability.</div>
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However in a later tutorial - the global ocean simulation - the inertial stability criterion is stated as: f^2*delta_t^2 > 1.0 for stability. </div>
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I.e., the inertial stability criterion in the global ocean simulation is much more lenient.</div>
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As far as I can tell, this tutorial also uses the Adams Bashforth time-stepping scheme. So i'm wondering if anyone could explain why a different inertial stability criterion applies here? and under what circumstances either version of this criterion should
be used?</div>
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Thank you for your time!</div>
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Flynn</div>
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