Empty sst_input

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Posts: 9
Joined: Mon Dec 21, 2020 1:24 pm

Empty sst_input

Post by maR_Kus » Mon Dec 21, 2020 1:44 pm

Hi All,

I have successfully created the wrflowinp_d01 file and now I am running WRF with options:

sst_update = 1,
sst_skin = 1,

However, looking at the variable SST_INPUT it contains all constant 0 values, although the SST are well defined into wrflowinp_d01. Besides, both SST and SSTSK display reasonable values, so I wonder how the model can simulate time-varying SSTs despite data from input are not read correctly? I am facing this issue in versions 3.8.1 and 4.2.

Thank you in advance for anyone who could help me to figure out what is going wrong.

Ming Chen
Posts: 1461
Joined: Mon Apr 23, 2018 9:42 pm

Re: Empty sst_input

Post by Ming Chen » Tue Dec 22, 2020 8:52 pm

WRF reads SST from wrflowinp at the specified intervals (auxinput4_interval ), then update SST and SSTSK. Please look at the file phys/module_surface_driver.F , and find the piece of code below:

! Update SST
IF (sst_update .EQ. 1) THEN
CALL wrf_debug( 100, 'SST_UPDATE is on' )
!$OMP PRIVATE ( ij, i, j, k )
DO ij = 1 , num_tiles
DO j=j_start(ij),j_end(ij)
DO i=i_start(ij),i_end(ij)
! check for lake model
#if (EM_CORE==1)
if ( lakemodel==1) then
if(lakemask(i,j).eq.1.) then
if ( xice(i,j).gt.xice_threshold) then !mchen


Hope this is helpful for you to understand how the sst_update option works.
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