[RegCNET] domain size

[BI XUNQIANG]

Hi, Prodromos:

You know, the equations of the Limited Area Models (RegCM3, MM5, WRF) we 
used are not written for the whole globe, instead, they are on one 
projected plane, like the Standard Lambert Projection, the plane goes 
through the two true latitudes: 30 and 60 degrees.

We usually use the equal-area grids in LAMs, whilst the global AGCMs use 
the Lat-Lon grids.

Hope it helps,
Xunqiang

On Mon, 12 Sep 2005, Prodromos Zanis wrote:

>
> Dear colleagues
>
> I had a confusion the last days with the borders of the domain in Regcm.
> If you have a 60x60 km grid resolution and you select iy=80 and ix=100
> grids, then  the domain size should be 4800 km x 6000 km.
>
> If I condsider this domain size and also the latitudinal dependence of the
> conversion between degrees and kilometers (e.g. at lat=23 N 1deg=102527 m
> while at lat=65N 1deg=47178 m) I get at the northern border of the domain
> longer longtitudinal size .
>
> To be more specific:
> iy=80
> ix=100
> clat=44 N
> clon=15 E
> ds=60 km (drid point separation)
>
> According to my calculations the latitudinal size of the domain Dy will
> extend from 22.67N to 65.33N.
> The longitudinal size will extend at the southern border from 13.8 W to 43 E
> and at the northern border from 49 W to 79 E.
> This longitudinal size of the domain at the northern border of the domain
> is much greater than I get from the regcm3 terrain (domain.ctl) using
> Lambert conformal projection.
>
> Do I miss something? Do you have any write-up for RegCM users than can help.
>

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~  Dr. Xunqiang Bi             email:bixq at ictp.it  ~ 
~  Physics of Weather and Climate Group            ~
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