I’m currently converting some modified SST ancillary files to use with the ESM1.5 - AMIP configuration. The source files are set up for CAM6, and have data exactly half way into each month (e.g. on March 15.5, April 15, May 15.5 etc each year).
However the data for the default SST ancillaries for the ESM AMIP configuration lie exactly 15.5 days into each month, independent of the month’s length. I was wondering if anyone knows how flexible the UM7.3 is for the ancillary time steps, i.e. does it require the data to occur 15.5 days into each month, or will it be fine to use the different time steps from the CAM6 files? I’ve tried looking into the documentation but haven’t found anything yet.
The reason I’m hoping to keep the CAM6 time steps is that the data has already been “diddled” so that it will recover the observed monthly means, and I’m hoping to avoid redoing that.
This does lead into a follow up question. The CAM6 data uses a 365 day calendar with no leap years, rather than the Gregorian calendar that ESM is using. I was wondering if anyone knows whether the differences that would occur in February on leap years would require the diddling to be redone, or if it would be small enough to safely ignore?
Thank you for your help!