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CNDV spunup and its output


New Member
I have several questions about CNDV.
1) In the CLM4.0 User's Guide Documentation example4-4, the modal provide spunup files. Does this file always exist in CLM?
2) Do spunup files get the CLMCN model to a steady state?
3)Following the steps given in Example4-4, I calculated 200 years, ①but the bare land area is huge. ②The calculation results in the 200th year are similar to the 30th year. ③Some types of vegetation have not grown. What is the reason for this result?


Keith Oleson
CSEG and Liaisons
Staff member
Note that CLM4 is no longer supported.
I'm also not sure if you are using CNDV (the dynamic vegetation version) or simply CN.
And I'm not sure what you mean by "file always exist in CLM".
That being said, spunup initial files are generally supplied for common configurations of the model, but there may be compsets/cases where a spunup file is not available.
The spunup files provided represent CLM at equilibrium for that particular configuration.
If you change anything in the model or in the forcing data, then you'll likely need to spin the model up again.
I can't really provide any answers to your last question without knowing what you are doing. This could be due to forcing data or any changes you've made to the model, or an error in setup.
Maybe someone else who is still using CLM4 can help.