About the f2000 extrinsic force

[lby]

1. Are all external forces of f2000 fixed? The FHIST, in contrast, is dynamic. I don't know if I'm getting this right.
2. By analogy, B1850 is fixed and BHIST is dynamic, right?
3. In what ways are B1850 and F2000 different?
Look forward to your answer, thank you

 

[dbailey]

That is essentially correct. The F2000 is a year 2000 control run where the greenhouse gases and other forcing are fixed at year 2000. The F compset is the so-called standalone CAM compset with specified SST and ice fraction as opposed to the B which is fully-coupled.

 

[lby]

That is essentially correct. The F2000 is a year 2000 control run where the greenhouse gases and other forcing are fixed at year 2000. The F compset is the so-called standalone CAM compset with specified SST and ice fraction as opposed to the B which is fully-coupled.

Thank you, dbailey. However, I am still confused about the difference between F2000 and B1850. My understanding is that F test is fixed ocean module to reduce the amount of calculation.
1. Will F test affect the simulation results? For example, I want to use F2000 to simulate the situation of 2000. Is he competent?
2. If it doesn't, why not?
Looking forward to your answer, thanks again

 

[dbailey]

These are more of a scientific question. I recommend checking out the AMIP literature for this. The short answer is that if you specify the SST, the climate conditions should be representative of 2000, but will not precisely be 2000.. However, a fully-coupled simulation (B) evolves freely on it's own. I recommend watching the lectures from the 2022 CESM Tutorial:

CESM Tutorial 2022 | Community Earth System Model

www.cesm.ucar.edu

 

[lby]

These are more of a scientific question. I recommend checking out the AMIP literature for this. The short answer is that if you specify the SST, the climate conditions should be representative of 2000, but will not precisely be 2000.. However, a fully-coupled simulation (B) evolves freely on it's own. I recommend watching the lectures from the 2022 CESM Tutorial:

CESM Tutorial 2022 | Community Earth System Model

www.cesm.ucar.edu

Glad to have your answer, dbailey. That would help me a lot. Thank you

 

[lby]

That is essentially correct. The F2000 is a year 2000 control run where the greenhouse gases and other forcing are fixed at year 2000. The F compset is the so-called standalone CAM compset with specified SST and ice fraction as opposed to the B which is fully-coupled.

Hello,dbailey.
I have some new questions recently. Is there such a test as B2000, which is to simulate the condition of 2000 years with full coupling, I found that there seems to be only B1850 and F2000. But I want to simulate the year 2000 in full coupling mode what if there is something I should do and set up?

 

[dbailey]

The B2000 is no longer supported. We decided that the year 2000 is not really a suitable control climate. However, I believe you can do it by replacing 1850 with 2000 in the long compset name and adding the --run-unsupported flag.

 

[lby]

The B2000 is no longer supported. We decided that the year 2000 is not really a suitable control climate. However, I believe you can do it by replacing 1850 with 2000 in the long compset name and adding the --run-unsupported flag.

Thank you, dbailey. Let me try it out