Opened 3 years ago

Closed 3 years ago

#2194 closed help (fixed)

Replanca error when modifying start date

Reported by: marcus Owned by: um_support
Component: UM Model Keywords: Replanca, startdump, start date
Cc: Platform: NEXCS
UM Version: 10.6


Hi, I am trying to set up suite u-am585 with start date 1960-09-01 on Monsoon to run on Nexcs.

I have replaced variable BASIS with BASIS='19600901T0000Z' and, as this didn't work, I also explicitly set i_override_date_time by replacing the $BYEAR variable with 1960,9,1,0,0,0 (this seemed not to be necessary when I wanted to start in the standard year 1988?).

Still, all fields in the startdump (which is successfully generated after reconfiguration) have the timestamp of 2008. The model then crashes during run with the error:

"REPLANCA: Current time precedes start time of data"

I have committed all my changes to rose here:

What else do I need to change to set the start date for the model run to 1960? This is unfortunately fairly urgent as we need to set off this run asap.

Many thanks,

Change History (10)

comment:1 Changed 3 years ago by grenville


setting i_override_date_time doesn't change the dump - it just overrides it.

Are you sure the ancil files are consistent with the new date — Replanca does the ancil updating

(there is lots of room for confusion with dates)


comment:2 Changed 3 years ago by marcus

Hi Grenville,

I presume you are referring to the ancil file that provides the five global fields with the long-lived source gases for reconfiguration. Yes, all five fields in there have the date 1960-09-01 00:00:00.


comment:3 Changed 3 years ago by grenville

How about ozone, ocean chlorophyll, sea ice and more ?

comment:4 Changed 3 years ago by marcus

Hi Grenville,

I must admit I am confused. I believe you might need to help me understand this.

Both the physical and the chemical initialisation files (from which the start dump is created) are for the year 2008 at N96. Still, it seemed easily feasible to start the model in 1988 which is the standard year for the off-the-shelf version of the model as far as I know?

By changing the model basis time and ensuring that the emissions and sea ice/SSTs are available for the appropriate time period (which is now the case for the ACSIS integrations) is it not possible to change the start date to 1960?

Based on what you wrote there seem to be more ancillary files that need changing? If yes, will these files need to be recreated or can I change this through a time flag in Rose?

Sorry, I seem to not understand the complexities that are involved here.

Thanks for your help,

comment:5 Changed 3 years ago by marcus

Does Replanca not tell us which ancillary file is the offending one?

comment:6 Changed 3 years ago by grenville


The leave file reveals all


  • FIELD 2 is sea ice (which is valid 1981_2012 /projects/um1/ancil/atmos/n96e/orca025/seaice/reynolds/1981_2012_360/v2/qrclim.seaice), similarly for ssts and possibly more.

So to run with your desired start date, you'd need to replace these files to include the appropriate data. I don't know where that data might be - if it exists at all.


comment:7 Changed 3 years ago by marcus

Thank you, Grenville. Oh dear, after setting up all the SSTs and SICE files we forgot to point at their respective directories in the ancils file. I will correct this and try again. Many thanks!

comment:8 Changed 3 years ago by grenville

Ahh - easily done

comment:9 Changed 3 years ago by marcus

OK, thanks Grenville, this has sorted this issue. However I am now a new issue with Lookup Headers however I will raise a new ticket (#2197) for this to keep things separate. Many thanks, Marcus

comment:10 Changed 3 years ago by grenville

  • Resolution set to fixed
  • Status changed from new to closed
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