SST less than -10 ℃

[hzh_1211]

Hi, everyone
In my roms-only simulations, I meet a big problem that is the SST appears outlier values(less than 10 ℃), as shown in below figure.
Forther more, the SST distribution is not smooth.

I have tested different situations:

boundary condition: Rad, RadNug, Clo
Vertical parameterization scheme: MY2.5 k-kl, k-epsilon, k-omega
Initial and Boundary field: SODA, HYCOM, [made by Agrif-matlab-toolbox or pyroms]
Bulk forcing field: CFSR, zeros everywhere

But the SST appears outlier values(less than 10 ℃) in every situations, so I doubt the roms grid file.
I made the roms grid file by Agrif-matlab-toolbox and GridBuilder [https://austides.com/downloads/] Separately.
I checked the rx0 factor of Beckman and Haidvogel that is less than 0.2, and the rx1 factor of Haney less than 6, that is ok.

I have no idea to solve this problom, please give some advise.

The detail infomation:
****************************************************
gird: 481*431*33
Vtransform=2
Vstretching=4
Theta_S=7
Theta_B=0
Tcline=100m
****************************************************
! 1 2 3 4

LBT(isFsur) == Che Che Che Che ! free-surface
LBT(isUbar) == Shc Shc Shc Shc ! 2D U-momentum
LBC(isVbar) == Shc Shc Shc Shc ! 2D V-momentum
LBC(isUvel) == RadNud RadNud RadNud RadNud ! 3D U-momentum
LBC(isVvel) == RadNud RadNud RadNud RadNud ! 3D V-momentum
LBC(isMtke) == Clo Clo Clo Clo ! mixing TKE

LBC(isTvar) == RadNud RadNud RadNud RadNud \ ! temperature
RadNud RadNud RadNud RadNud ! salinity
****************************************************

[kate]

Have you looked at the boundary file? Is that where you have inflow going on? It does look like a boundary problem to me.