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iCESM 1.2: some questions about pi control and spinup

gaoyuan

Yuan Gao
New Member
Dear all,
Hi, I am a postgraduate student with a keen interest in CESM. I try to utilize iCESM 1.2 to run a B1850C5CN pi control test at a T31g37 resolution, but I am a novice. Now I have two problems.
I created a new case with the resolution set to "T31_g37", compset as "B1850C5CN", and RUN_TYPE as "startup". About iCESM_restart_files, i used "finidat = '/public/home/hujun/gaoyuan/clmi.BCN.0507-01-01_48x96_gx3v7_simyr1850_c120929.nc'" >> user_nl_clm.I ignored(not changing) other things about the model.
I want to know how long can the model spin up. In $casename.cam.h0.time.file, If FSNT-FLNT is between -1 and 1, then the atm model is balanced. Now I running for about 600 years, but it seems not good[fig.1]. I do not know why it needs so long time to balance. My classmate ran the B1850C5CN pi control test at an f19g16 resolution, using finite = clmi.Bi1850CN.0401-01-01_1.9x2.5_gx1v6_simyr1850_c150724.nc, he only needs 100 years than can be balanced. I do not why.
In addition, I use the variable TEMP in $casename.pop.h.me (I see that its 41st layer represents a water depth of 100000mm). I once read an article that suggested that if the water depth below 1000m has a change of less than 0.05 degrees Celsius in ten years, then it is considered to be in equilibrium. I was puzzled by the fact that the temperature at a depth of 1000m was rising and was now nearly 9 degrees(fig.2).

Sincerely hope to get your advice.
Best wishes!


balance_atm.pngbalance_ocean.png
 

gaoyuan

Yuan Gao
New Member
hi, I find TEMP is potential temperature, it may be less than temperature. but I do not why the temperature at 1000 m in the ocean is so high. Could anyone help me?
 
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