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(RESOLVED) Use of SST in WRF model projections

This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.


New member

I have kind of a conceptual question about the SST input field.
I am using CESM as input to WRF which does have time-varying SST.

I understand that WRF doesn't generate SST projections, unless activated through the namelist options as explained here

What I want to know is that for a simulation e.g. 1st Jan 2020-31st Dec 2020, so does the entire simulation use time varying SST provided through the CESM input? As in the projection for lets say 1st June uses the SST for 1st June from the CESM input?
or does it just use the SST of 01/01 (which is the first time-step) for the entire year's simulation?

Would be very grateful for any explanations.
I first would like to apologize for the long delay in response. I've been traveling for a few weeks and am just now catching up with forum inquiries. Thank you for your patience.

SST can be either calculated at the initial time only, or it can be calculated at multiple input times. If you scroll to the bottom of the page you mention, from the online tutorial, you can see the ways to use 2 different options. For a year-long domain, you will want to have it calculated at multiple times.
Hi Kelly,

Thats no problem I can understand.
I didnot get separate high resolution SST for my simulations. However what I did was that while using the CESM to drive my simulations, I did add 'SST' in the namelist.wps &metgrid section. And I also added following in the &domain section the following.

auxinput4_inname = "wrflowinp_d<domain>",
auxinput4_interval = 360,
io_form_auxinput4 = 2

and the following the &physics section:

sst_update = 1,
sst_skin = 1,

Though I am not particularly interested in the SST output from WRF, as my work is mainland Norway. However my supervisor's point was that the whole simulation in the coastal areas specially would be biased if SST is not updated because for example if the simulation starts in Nov and ends in April, how come Feb, March are using SST set for Nov. Anyways, I can see from the TSK variable WRF output over my domain that there is a difference between the plots when I wasn't updating the SST as compared to after updating SST.
Ok, great! I'm glad you were able to see the difference, and I agree with your supervisor that it's important to update the SST, even if your main point of interest is on land, as it's all related.