What initial conditions files should be used for an aqua-planet simulation? Is it possible to start with a set of standard OpenIFS initial conditions? Also how easy would it be to specifiy a highly idealised basic state / initial conditions? The reason I ask is that i am wondering if it would be possible to do a series of aqua-planet simulations changing things like the SST gradient, the position of the jet stream ect. to see how this affects certain aspects of the circulation (e.g. extra-tropical cyclones).
Victoria Sinclair
3 Comments
Glenn Carver
Hi Victoria,
There is some information about configuring Aqua-planets with OpenIFS. I expect you've seen this.
The aqua-planet in the OpenIFS code is based on the Neale & Hoskins, 2001, ASL, paper. If you look in ifs/phys_ec/gp_sstaqua.F90, the different SSTs described in the paper are set up there. Other factors in the model, like gravity, are also altered in OpenIFS to match the Neale & Hoskins experiments. The various idealized starting conditions are shows in ifs/setup/suspecg2.F90 and see also ifs/module/yomdyncore.F90.
The difficulty is that these options are not always maintained and some work would be required to check. Changing the SST gradient would be possible in a similar way to the code in OpenIFS now but it would require some work - hard to say how much.
The model can be started from real conditions as long as the land-sea-mask and surface geopotential (orograph) are set to zero (by using grib_set). I am adding more information to the OpenIFS webpage for this setup.
Glenn
Victoria Sinclair
Hello,
I have a few questions related to the aqua-planet set-up of OpenIFS.
Thanks in advance,
Victoria
Gabriella Szepszo
Hi Victoria,
Many thanks for your careful inspection!
Consulting with colleagues from physics about the problem with short wave radiation: the possible reason is that the low cloud cover is much lower than expected, especially there are no subtropical Sc areas, also less clouds in polar regions. They proposed you to decrease either autoconversion in microphysics and/or decrease erosion rate for cloud fraction.
Gabi