Re: wrf_rh

       SUBROUTINE DCOMPUTERH(QV,P,T,RH,NX)

       IMPLICIT NONE
       INTEGER NX
       DOUBLE PRECISION QV(NX),P(NX),T(NX),RH(NX)
C NCLEND
       DOUBLE PRECISION SVP1,SVP2,SVP3,SVPT0
       PARAMETER (SVP1=0.6112D0,SVP2=17.67D0,SVP3=29.65D0,SVPT0=273.15D0)
       INTEGER I
       DOUBLE PRECISION QVS,ES,PRESSURE,TEMPERATURE
       DOUBLE PRECISION EP_2,R_D,R_V
       PARAMETER (R_D=287.D0,R_V=461.6D0,EP_2=R_D/R_V)
       DOUBLE PRECISION EP_3
       PARAMETER (EP_3=0.622D0)

       DO I = 1,NX
          PRESSURE = P(I)
          TEMPERATURE = T(I)
c es = 1000.*svp1*
          ES = 10.D0*SVP1*EXP(SVP2* (TEMPERATURE-SVPT0)/
      + (TEMPERATURE-SVP3))
c qvs = ep_2*es/(pressure-es)
          QVS = EP_3*ES/ (0.01D0*PRESSURE- (1.D0-EP_3)*ES)
c rh = 100*amax1(1., qv(i)/qvs)
c rh(i) = 100.*qv(i)/qvs
          RH(I) = 100.D0*DMAX1(DMIN1(QV(I)/QVS,1.0D0),0.0D0)
       END DO

       RETURN
       END

On 4/19/12 9:25 PM, Mittal, Moti wrote:
>
> Masha,
>
> Thank you very much for the pointer.
> I looked at it. It defines
> Rh= wrf_rh(QVAPOR, P,Tk)
>
> I want to know how the funcation wrf_rh(QVAPOR, P,Tk) computes rh.
> I am looking for the source code for this function.
> Thanks for the discussion.
>
> Moti
> ________________________________________
> From: Masha Tsukernik [mariatsuk@gmail.com]
> Sent: Thursday, April 19, 2012 11:12 PM
> To: Mittal, Moti
> Cc: ncl-talk@ucar.edu
> Subject: Re: wrf_rh
>
> Moti:
> You can look for the source code in the WRF library
>
> $NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl
>
> Hope that helps,
> Masha
>
> On Thu, Apr 19, 2012 at 11:03 PM, Mittal, Moti<mmittal@health.usf.edu> wrote:
>> Hallo,
>>
>>
>> I need help to calculate relative humidity from WRFoutput.
>>
>> I checked the scripts and found a built in function wrf_rh.
>>
>> I want to learn the formula from which you build this function.
>> Is it possible to know the formula for relative humidity from water vapour
>> mixing ratio, pressure, and temperature?
>>
>> Moti
>>
>> _______________________________________________
>> ncl-talk mailing list
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Wed Apr 25 10:28:23 2012