Radiation output times offset


I’ve noticed that for any radiation variables I output there’s an offset in time from any other output I get. I am running a RNS setup on monsoon and have requested 15 min (instantaneous) radiation output. However when I look at my radiation output the timestamps do not say 0,15,30,45 minutes as I would expect but says 15:04,30:04,45:04,00:04 all offset by 15 minutes plus whatever the model timestep is (4 seconds in this case). For most applications this offset effectively by 4 seconds is not important but in the future I would like to understand what is going on and try to get the radiation out at the time I expect. The suite I’m working on is u-cv482.

Thanks a lot for your help,

Hi Russell

This is how the UM works - radiation diagnostics are labelled by the end of the time step.

u-cv482 has lts0 = .true. for T15MIN which probably accounts for starting at 15.


I see so this is standard behavior for radiation output, all timestamps are from the end of the time step whereas other UM output is from the beginning?

I have other stash output on the same time domain but only radiation has this 15 min offset. But if I understand, radiation stash is affected by this lts0 setting but others are not?

Thank you