CESM Models

CESM1.1: POP2 Port Validation


In a successful port, CESM POP2 ocean-model solutions are expected to be the same "to roundoff level" as solutions generated on a trusted machine, although determining what is and what is not roundoff level is somewhat difficult and subjective. Presently no automated testing tools exist for validating the successful port of the CESM POP2 model to a new system.

In order to facilitate the evaluation of a successful port, we suggest that you set up and run on your local machine the cases described in the Port Validation Procedure document below.

When time permits, we plan to create scripts to automatically set up and run those cases, but until then, you will need to apply these steps manually.

Following the successful execution of these cases, you can use the ncl SSH RMS difference script to create plots and compare them with the results linked below in the "Port-Validation Plots" section in order to validate your port.

Port-Validation Procedure

Port-Validation RMS Difference Script

Port-Validation Plots

WARNING: the port to Yellowstone has not actually been verified as successful yet. Information below here is simply a place-holder... this warning will be removed once the port to Yellowstone has been OKed!

The following plots illustrate a successful port to the NCAR IBM iDataPlex yellowstone. The plots display timeseries of RMS differences of the SSH field between the yellowstone solutions and those generated on a "trusted machine," the NCAR IBM bluefire.

Note that the time axis on the following plots is in the range [366.0,370.], because the cases start from year 1; thus the plots show results for the first five days of a startup run.

The following plots were produced on 27 November 2012 with the cesm1_1 release code.

The following plots illustrate acceptable RMS SSH differences in POP2 solutions on trusted machines (bluefire and yellowstone) due to differences in pe count and convergence criteria.

Port-Validation Data

Port validation datasets generated on bluefire and yellowstone are available on this website in the following two tar files. The datasets were generated using the cesm1_1 tag in November 2012.