Opened 12 months ago

#3449 new help

What does the l_mask_snow_orog switch actually do?

Reported by: jmackay Owned by: jules_support
Component: JULES Keywords: jules snow orographic albedo
Cc: Platform: Other
UM Version:


Hi all,

I'm currently using jules to simulate mountain snow-ice accumulation and melt. I've noticed that there is a l_mask_snow_orog switch as part of the radiation namelist. The description in the JULES manual states that it is a, "Switch for orographic masking of snow, which decreases the albedo of snow in mountainous regions."

I've looked at the revision history and it looks like it was introduced as part of JULES v4.3. However, when I access the trac to get some documentation on what it actually does, the links just take me to a "forbidden" met office web page. I guess the links are broken.

Does anyone know what this switch actually does? Why would you want to preferentially decrease snow in mountainous areas and, if as it states, it uses the orography to control this, how does jules establish where the mountains lie?

Many thanks in advance for any help with this


Change History (0)

Note: See TracTickets for help on using tickets.