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There are several ways you can determine a projected usage:
(a) Under Method 1: Under the $CASEROOT/timing
folder in a CESM simulation setup, you can find entries for Model Cost and Model Throughput. From those numbers you can estimate the CPU hours necessary for your simulation requirements and then break it up into reasonable weekly requests.
Example CESM simulation timing spreadsheet
(b) Method 2: Use the UCAR HPC online usage tracking system https://sam.ucar.edu/
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