Using the Gregorian Calendar in UM Climate runs

The Met Office use a 360 day calendar by default and provide all their example jobs with this calendar. The ACCESS climate configurations use the Gregorian calendar, so modifications need to modify Met Office jobs for our use.

  • In addition to setting the calendar to Gregorian, we use code changes to allow monthly dumps (speeds up the code considerably compared to daily dumps which is the default).
  • The procedure for setting up the Gregorian calendar with monthly dumps from vn8.5 onwards is slightly different from previous versions.

Steps to set up Gregorian calendar job in umui for vn8.6

  • An example job at vn8.6 is vaaoe
  • Input/Output Control and Resources -> General Configuration and Control
    • Use 360 day calendar = 'OFF'
  • Post Processing -> Initialization and processing of mean and standard PP files
    • Select 1 RM (real month) rather than 30 DA, for the period of reinitialisation of PP files
  • Include branches:
    • fcm:um_dev/pfu599/vn8.6_reduced_greg_dump (allows the monthly dump)
    • fcm:um_dev/pfu599/vn8.6_ignore_calendar (cause the UM to ignore the calendar flag when reading ancillary files). Alternatively, ancillary files can be rebuilt for the Gregorian calendar.
  • Use hand edit:
    • ~access/umui_jobs/hand_edits/common/reduced_greg_dump.ed


  • Example job is vaami
  • Branch for vn8.5 GA6:
    • fcm:um_dev/mrd599/vn8.5_GlobalAtmos6p0_gregorian
Last modified 5 years ago Last modified on Oct 20, 2016 2:18:32 PM