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The time resolution ?

rongbing0353

8410788
New Member
I have a question, I know that the space resolution of CESM is about 1.9°*2.5°,yet, I can't find the time resolution of the CESM, Furthermore, when I am making a DUST PM2.5 inventory ,I don't know how to revise the inputdata? and where is it exactly I should make a change of the inputdata? Thanks for your guys help
 

fischer

CSEG and Liaisons
Staff member
Hi,

I can answer the question about the time steps. In env_run.xml there's NCPL_BASE_PERIOD, this sets the base period for the time steps.
Also in env_run.xml there's several NCPL variables for each component. You can see all of these variables by doing

./xmlquery --listall | grep NCPL

You'll get a list something like this.

ATM_NCPL: 48
GLC_NCPL: 1
ICE_NCPL: 48
LND_NCPL: 48
NCPL_BASE_PERIOD: day
OCN_NCPL: 24
ROF_NCPL: 8
WAV_NCPL: 48

You'll take NCPL_BASE_PERIOD and divide by the component NCPL. For example ATM_NCPL of 48 would be a 30 minute time step, OCN_NCPL
would be a 1 hour time step.

I can't answer the question about DUST PM2.5 inventory since I'm not sure what model component this is for.

Chris
 

rongbing0353

8410788
New Member
Hi, @fischer ,I'm so appreciate your reply, I'm still confused about it, because all my inputdata(an inventory of the air pollutants) is made for time step is YEAR, not month or day, minute, you said that the NCPL_BASE_PERIOD: day, can i confirm that
ATM_NCPL: 1/365
GLC_NCPL: 1/365
ICE_NCPL: 1/365
LND_NCPL: 1/365
NCPL_BASE_PERIOD: day
OCN_NCPL: 1/365
ROF_NCPL: 1/365
WAV_NCPL: 1/365
? Is it wrong or right I mentioned above? Thank you very much
 

emmons

Louisa Emmons
Moderator
Staff member
Could you please clarify what you are trying to do? Dust is calculated online in CESM, as it depends on windspeed. Also PM2.5 is only a diagnostic in CESM - it is calculated from the sum of specific aerosols (e.g., so4_a1, so4_a2, bc_a1, pom_a1, dst_*, etc.)
If you create a default case you can see what standard emissions files look like. They require the 'date' variable and emissions are interpolated between whatever dates are provided in the emissions files (daily, monthly, yearly, etc.)
 

rongbing0353

8410788
New Member
Could you please clarify what you are trying to do? Dust is calculated online in CESM, as it depends on windspeed. Also PM2.5 is only a diagnostic in CESM - it is calculated from the sum of specific aerosols (e.g., so4_a1, so4_a2, bc_a1, pom_a1, dst_*, etc.)
If you create a default case you can see what standard emissions files look like. They require the 'date' variable and emissions are interpolated between whatever dates are provided in the emissions files (daily, monthly, yearly, etc.)
Hi,emmons, I appreciated so much for your reply, I'm making an inventory for the dust emissions, which is created by myself, and it is different from the default inputdata in the CESM usually required. Because my inventory is made by the space resolution is 0.5°*0.5°,and the time steps are year, I mean I just made the inventory by the resolution of a whole year, I can't make the inventory by month or day, and my question is how I can make the change, and what and where I should do in the CESM to revise the default setings.For the inventroy i made mainly for the atmosphere research, so I wanna run the coupled model, rather than the single model of CAM6 or CLM. please give me some advices, thanks a lot.
 
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