[RegCNET] precipitation's unit

[bixq]

Hi, Shenghui:

Different from other regional models (MM5, WRF), in RegCM, the 
precipitation (evp and runoff) unit is always in mm/day
(in both ATM file and SRF file).

You just need to take the average of them to get the monthly mean (also in 
mm/day), if your observation data are the accumulated amount, then you 
need use the monthly mean times number of day in that month.

like,

d ave(tpr,t=1,t=248)*31

for your case.

By the way, mm/day unit is also used by a lot of observation data, like 
CMAP, CRU, etc.

Regards,
Bi Xunqiang

On Wed, 10 Mar 2010, sh zhou wrote:

> Hi,
>
> I want to display the precipitation for one day, but I found the unit for
> "tpr" is "mm/day", and there are 8 times output  everyday ( the interval is
> 3h), so, why some variables like "tpr, evp runoff" unit set with "mm/day"
> which also has values for each time in output?  how to use it? Thank you.
> this is my data description :
> ga-> q file
> File 1 : RegCM normal output variables
>  Descriptor: SRF.1998070100.ctl
>  Binary: SRF.1998070100
>  Type = Gridded
>  Xsize = 383  Ysize = 216  Zsize = 1  Tsize = 248  Esize = 1
>  Number of Variables = 27
>     u10m  0  33,105  westerly  wind at 10m (m/s)
>     v10m  0  34,105  southerly wind at 10m (m/s)
>     uvdrag  0  99  surface drag stress
>     tg  0  99  ground temperature (degree)
>     tlef  0  99  temperature of foliage
>     t2m  0  99  air temperature at 2m (K)
>     q2m  0  99  water vapor mixing ratio at 2m(kg/kg
>     ssw  0  99  upper layer soil water
>     rsw  0  99  root zone soil water
>     tpr  0  99  total precipitation (mm/day)
>     evp  0  99  evapotranspiration (mm/day)
>     runoff  0  99  surface runoff (mm/day)
>     scv  0  99  total snow amount
>     sena  0  99  sensible heat flux (W/m2)
>     flw  0  99  net infrared energy flux (W/m2)
>     fsw  0  99  net absorbed solar energy flux (W/m2
>     flwd  0  99  downward infrared energy flux (W/m2)
>     sina  0  99  incident solar energy flux (W/m2)
>     prcv  0  99  convective precipitation (mm/day)
>     psb  0  99  surface pressure (hPa)
>     zpbl  0  99  PBL layer height
>     tgmax  0  99  maximum ground temperature (K)
>     tgmin  0  99  minimum ground temperature (K)
>     t2max  0  99  maximum 2m air temperature (K)
>     t2min  0  99  minimum 2m air temperature (K)
>     w10max  0  99  maximum 10m wind speed (m/s)
>     ps_min  0  99  minimum surface pressure (hPa)
> ga->
>
>
> -- 
> Shenghui                    Student
> Major:                         Physics
> HuNan University          China
>

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   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
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~