# Re: Divergence

From: Guilherme Martins <jgmsantos_at_nyahnyahspammersnyahnyah>
Date: Wed Jul 24 2013 - 10:00:47 MDT

My question is: The values using the function uv2dvG make sense? I multiply
"divg" by "humidity specific" because I want humidity divergence.

f = addfile("uvq.1000hpa.nc","r") ; gaussian grid

u = f->uvel(0,0,:,:) ; m/s
v = f->vvel(0,0,:,:) ; m/s
q = f->umes(0,0,:,:) ; kg/kg
dv = uv2dvG(u,v) ; divergence - gaussian grid

divg = dv * q

Thanks,

Guilherme.

2013/7/24 Dennis Shea <shea@ucar.edu>

> Not sure what you want.
>
> The units of divergence are 1/sec
> --
> Embedded in the long_name ... units are m/s
>
> float uvel ( time, lev, lat, lon )
> long_name : ZONAL WIND (U) (M/Sec
> )
>
> float vvel ( time, lev, lat, lon )
> long_name : MERIDIONAL WIND (V) (M/Sec
> )
>
> float umes ( time, lev, lat, lon )
> long_name : SPECIFIC HUMIDITY (No Dim
> )
>
> If the largest values of 'umes' are (say) 20 then the
> units are g/kg; if the largest values are (say) 0.002
> they are kg/kg (ie unitless)
>
> ====
> The code you sent indicates this already
>
> u = f->uvel(0,0,:,:) ; m/s
> v = f->vvel(0,0,:,:) ; m/s
> q = f->umes(0,0,:,:) ; kg/kg
> dv = uv2dvG(u,v) ; divergence - gaussian grid
>
>
>
>
>
> On 7/24/13 9:10 AM, Guilherme Martins wrote:
>
>> Hi all,
>>
>> I'm calculating the divergence, but I'm not sure about the units of the
>> variables. Can anyone help me?
>>
>> The files are in attach.
>>
>> Thanks,
>>
>> Guilherme.
>>
>>
>>
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```--
*Guilherme Martins*