Hi,
I have a question about the spin-up simulation. For the spin-up period, do i need to use the real input data? For example, i want to run a hemispheric simulation for the year 2019, and i want to use 2018 as my spin-up year. For the spin-up simulation of year 2018, do i need to use meteorological inputs and emission inputs of the year 2018? Can i use inputs for 2019 to run the spin-up simulation of 2018?
Thanks,
Lin
If you expect year-specific 2018 features (in emissions and/or meteorology) to have important impacts on the long-lived species that you’d like to have fully spun up by the time you start your “real” simulation on January 1, 2019, then it would be advisable to use fields that represent those features for your spin-up modeling.
If that isn’t the case, first performing a 2019 full year “spin-up” run and then time-shifting December 31, 2019 outputs back to December 2018 to start your “real” 2019 simulation should work (I think that’s what you mean by “use inputs for 2019 to run the spin-up simulation of 2018” - you cannot set CCTM simulation dates to dates that aren’t included in your MCIP files).
That make sense! Thanks so much!
Lin
Hi Christian,
I have a follow-up question. If i changed a parameter of the model, for example, a Hg re-emission parameter, do i need to rerun the spin-up ?
Thanks,
Lin
Hello Lin,
I’m not familiar enough with Hg processes and lifetimes to provide a definitive answer. But if you expect that the effects of the process change in your sensitivity simulation will take some time to fully manifest themselves across the modeling domain, you would probably want to have a spin-up period for your sensitivity simulation that’s long enough such that by the time you start your analysis, the effects of the process change have fully established themselves across the entire domain.
Got it!
Thanks so much!
Lin