what does "halo" mean in WRF code

[bruceyoung01]

I searched in WRF code and found tons of places using the word "halo". What does it mean in WRF? Thank you

 

[kwerner]

Hi,
When using multiple processors, your domain is divided up into a grid, based on the number of processors you are using - 1 processor is assigned to each grid cell. Each grid cell has a halo region that consists of a few rows (minimum of 5) on each of the 4 sides. The halo region is used to pass grid information from that particular grid cell to its neighboring grid cells.

 

[mirabelle]

Mr. kwerner

I need to use neighboring grid cells information on particular processor.
For example, I want get No.2 processor's information when I am in No.1 processor.
Do you know how to get the information from neighboring grid cells？

And I have asked the question at another link.
https://forum.mmm.ucar.edu/phpBB3/viewtopic.php?f=47&t=11035&p=24031#p24031

Thank you

 

[kwerner]

I can see in the link to your question on another post, that you already received a reply. Please try to refrain from posting the same question multiple times throughout the forum, as it adds to the time we must spend to respond to questions. Thanks!