What 's mean of the name of CCSM4 model output

[lixz@ieecas_cn]

Hi,
I want to know the mean of the word "track" in name of b40.1850.track1.1deg.006 data.
http://www.earthsystemgrid.org/browse/viewDataset.htm?datasetId=ea92730f-52da-4cd2-a3dc-5e1b9db3348a

 

[eaton]

This is an internal designation for one of the configurations of CAM that were candidates to become CAM4. track1 is the candidate that was released as CAM4.