Re: [ferret_users] pentad_climatology and anomaly

[chinnu sachi <chinnu.sachi7@xxxxxxxxx>]

I am getting the climatology now. Thank you for a fast reply

On Fri, Dec 6, 2013 at 4:54 AM, Ansley Manke <ansley.b.manke@xxxxxxxx> wrote:

Hello,
First a suggestion - when asking a question, I would suggest including the commands you have tried, so we might see what's going on.

You can define your own custom climatological axis. Have a look at this FAQ about creating a daily climatology.
http://ferret.pmel.noaa.gov/Ferret/faq/creating-a-daily-climatology

I think you could use similar commands, but give the delta-time as 5 days instead of 1 day.  Ferret will handle time axes with leap years.  See the discussion of Calendars in the Users Guide, Chapter 4 Section 4.2.2 "Time axes and calendars", and read about the /MODULO qualifier for DEFINE AXIS.

Let me show how I went about looking at this. Try an axis definition. Use /EDGES so that the coordinates will be at day 2.5, spanning days 1-5, and so forth.

yes? define axis/T=0:365.2425:5/edges/T0=1-JAN-0001/UNITS=DAYS/MODULO t5day

yes? show axis t5day
 name       axis              # pts   start                end
 T5DAY     TIME                74mr   03-JAN 12:00         03-JAN-0002 12:00
T0 = 1-JAN-0001
   Axis span (to cell edges) = 370 (modulo length = axis span)

   ! List some of the timesteps at the start and end of the axis.

yes? list/l=1:5 t[gt=t5day]
             VARIABLE : T
                        axis T5DAY
             SUBSET   : 5 points (TIME)
 03-JAN 12      / 1:   2.50
 08-JAN 12      / 2:   7.50
 13-JAN 12      / 3:  12.50
 18-JAN 12      / 4:  17.50
 23-JAN 12      / 5:  22.50

yes? list/l=70:74 t[gt=t5day]

             VARIABLE : T
                        axis T5DAY
             SUBSET   : 5 points (TIME)
 14-DEC 12      / 70:  347.5
 19-DEC 12      / 71:  352.5
 24-DEC 12      / 72:  357.5
 29-DEC 12      / 73:  362.5
 03-JAN-0002 12 / 74:  367.5

The axis is a bit longer than a year, because 5-day steps don't fit into a year exactly.  You'll want to use one less point:

yes? define axis/T=0:365.2425:5/edges/npoints=73/T0=1-JAN-0001/UNITS=DAYS/MODULO t5day

yes? list/l=70:73 t[gt=t5day], tboxhi[gt=t5day]
             TIME: 12-DEC 05:30 to 01-JAN-0002 05:49
 Column  1: T is T (axis T5DAY)
 Column  2: TBOXHI is TBOXHI (axis T5DAY)
                         T  TBOXHI
14-DEC 17      / 70:  347.7  350.2
19-DEC 17      / 71:  352.7  355.2
24-DEC 17      / 72:  357.7  360.2
29-DEC 17      / 73:  362.7  365.2

Now you can regrid your data to this axis using the @MOD regridding transformation.

Ansley

On 12/5/2013 3:44 AM, chinnu sachi wrote:

Dear ferret users,

I want to calculate pentad climatology and anomaly for 50year data set. I got the jnl file from user's group to do pentad climatology, now the problem is, jnl file is working fine without giving error but the output file doesn't had any values;means climatology is not calculating,only file is creating. And my data had leap year.

Thanks in advance.

--
Regards,
Chinnu Sachidanandan
Physical Oceanography Division