[RegCNET] underestimated diurnal temperature range montly means?

[Matteo Zampieri]

Hi Xunqiang,

thank you very much for your kind reply

I'm using the standard postprocessing (postproc.f)

maybe there is something wrong in the settings of
my postproc.in, which is:

1994010100,     ! idate0 = First date in File (yymmddhh)
1994010100,     ! idate1 = Start date for averaging and re-writing
1995010100,     ! idate2 = End date for averaging and re-writing
2,              ! iotype: 1=I*2 NetCDF; 2=r*4 NetCDF; 3=grads; 4=vis5d
.false.,        ! plv
.false.,        !
.false.,        ! Write out header?
.false.,        ! Write out all RegCM data b/twn idate1 & idate2?
.false.,        ! Average RegCM data b/twn idate1 & idate2?
.false.,        ! Diurnali avg of RegCM data b/twn idate1 & idate2?
.true.,         ! Continually average ATM data b/twn idate1 & idate2?
-1.,            ! No. Days for continual averaging
(-1=monthly;1=daily;5=5day)
etc

or is it ok?

thank you very much in advance

bests,
Matteo

>
> Hi, Matteo:
>
> I guess that the way of your calculation might not be correct.
>
> Which way you used ?
>
> If you like, you can try my postproc (DAY_SRF.f under
> RegCM/Commons/DAY_MONTH),
>
> Suppose you output SRF fields every 3 hour. then in SRF.yyyymmddhh
> file, you have 8 time slices in one day. The right way to calculate
> TAMAX is find the maximum among the 8 time slices firstly, then
> do the average of those maximun to get the monthly mean.
>
> You should do for TAMIN in a similar way. Then calculate the
> TGMAX - TGMIN. I am sure you should get the magnitude greater than 1K.
>
> Best regards,
> Xunqiang Bi
>
>
> On Mon, 2 Jul 2007, Matteo Zampieri wrote:
>
>> Hi All,
>>
>> I'm using RegCM over Europe, I'm doing an hindcast for year 1994
>> using a similar configuration of the Practice Run but with a wider
>> area and using ERA40 as boundary conditions (domain.param is attached)
>>
>> I think that the model diurnal temporal range, computed as TAMAX-TAMIN
>> from the SFR file after montly means are computed, is underestimated.
>>
>> I'm attaching two plots showing the mean diurnal temporal range for
>> january and august. In January, in Central Europe, it is only 1 K
>>
>> Maybe a possible reason could be that tamax and tamin are computed from
>> the 4-hourly model output but I don't think it is enough to explain
>> this behaviour
>>
>> thank you very much to anyone can help me!
>>
>> bests,
>> Matteo
>>
>> ---------------------------------------------
>> Matteo Zampieri
>> ISAC-CNR
>> Strada Prov. Lecce-Monteroni km 1.2
>> 73100 LECCE (IT)
>> email: M.Zampieri at isac.cnr.it - @lmd.ens.fr
>> Tel: +39 0832 29 7105 - Fax: +39 0832 29 7547
>> ---------------------------------------------
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>    Dr. Xunqiang Bi         email:bixq at ictp.it
>    Earth System Physics Group
>    The Abdus Salam ICTP
>    Strada Costiera, 11
>    P.O. BOX 586, 34100 Trieste, ITALY
>    Tel: +39-040-2240302  Fax: +39-040-2240449
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>