## Query about Domain

All things relating to the WRF Domain Wizard tool

### Query about Domain

Dear sir,

I am working in wrf model from a few months. Actually i have a query about the making of a new domain also a nested domain. Suppose i want to make the domain for whole india than how to select i_parent, j_parent, e_we points and e_sn points. I have consider center lattitude 23.52 and center longitude 79.65. Another thing is actually what i have to take as the standard longitude. Kindly give a solution if possible.

Amar
Amarjyoti Kalita

Posts: 2
Joined: Thu Jan 17, 2013 1:30 am

### Re: Query about Domain

Hi,

I always find it helpful to draw a little sketch, and what comes next is some simple math.
Just think: what is your dx and dy, and how many grid points with that size (dx, dy) do you need to get from the center of your domain to the boundaries, covering the area of interest? That's your e_we/e_sn.

Run geogrid/ungrib/metgrid and take a look at your domain.
Adjust the domain setup if necessary.

--AchternDiek
AchternDiek

Posts: 147
Joined: Wed Jun 06, 2012 6:10 am
Location: Norway

### Re: Query about Domain

Dear
AchternDiek,

Suppose i use central lat lon (24, 82) to make the grid domain of india sub continent. I took dx=27000 m dy=27000 m. The latitude difference and the longitude difference for the india region is converted from degree to meter scale. After that the latitude and longitude difference is divided by 27000 m. i.e. dlat/dx and dlon/dy. That has to be taken as e_we and e_sn. Is it the write procedure? Now if I want to make a domain for north east region within indian domain now how to select thye value of i_start, j_start and i_end, j_end. then finally e_we and e_sn.

amar
Amarjyoti Kalita

Posts: 2
Joined: Thu Jan 17, 2013 1:30 am

### Re: Query about Domain

Hi,

To know how to set i_parent_start, j_parent_start, e_we and e_sn, check my post viewtopic.php?f=24&t=9185&p=25868#p25868

Also, stand_lon is the longitude parallel to the y-axis in conic and azimuthal projections. Check the section "Step 1: Define model domains with geogrid" from http://www2.mmm.ucar.edu/wrf/users/docs ... _chap3.htm

Normally, when I use 'mercator', ref_long = stand_lon.
Hydrology Researcher, University of Bristol
alainaketh

Posts: 36
Joined: Fri Jun 26, 2015 12:30 pm