Model Spinup

[Ashwin D]

Temporally, yes, as mesoscale processes don't evolve fast enough for a 15-minute interval to severely hamper or truncate mesoscale-resolvable features. Spatially, however, the input to a mesoscale model from a global model would be missing all features below the scales resolvable by the global model. Granted, many mesoscale processes are driven by synoptic scale processes that are resolved on global model grids, but not all of them (espeically those that are orographically forced). Anything related to gravity wave drag would also likely be missing in the mesoscale model input.

Jeff,
Apart from being a senior research meteorologist you are also into storm chasing. From your operational experience what is the maximum surface pressure drop you have observed in a interval of 3 hours ?
Ashwin.

 

[Jeff Duda]

Jeff,
Apart from being a senior research meteorologist you are also into storm chasing. From your operational experience what is the maximum surface pressure drop you have observed in a interval of 3 hours ?
Ashwin.

I don't know...5 mb +/- 3 mb?

 

[Ashwin D]

I don't know...5 mb +/- 3 mb?

Ok I guess what I am looking at are edge cases i.e. if that surface pressure drop is indeed observed in say a 15-20 minute interval would the GCM miss resolving that ? I guess not because the time step is around 15 minutes.

 

[Robert Edmonds]

On a separate note, for climate studies for Mars you often started the model with no winds, isothermal, etc. Let it run a year or two in model time before exploring what you're interested in. That's about as crude of a way to spin a model up.

 

[Jeff Duda]

On a separate note, for climate studies for Mars you often started the model with no winds, isothermal, etc. Let it run a year or two in model time before exploring what you're interested in. That's about as crude of a way to spin a model up.

Yeah, anything you want as long as it is physically possible (i.e, you wouldn't be able to start up with all zero fields...like temperature).