BEP NOAH-MP and WRF-LES interaction

[jphorne]

Hello,

I have been digging through the source code and looking for the answer to this question, but I have been unable to find what I am looking for. Maybe someone here knows where this is occurring.

Okay, so I am running a WRF-LES simulation with NOAH-MP and BEP. I want to determine how WRF-LES interacts with NOAH-MP and BEP when calculating variables such as T2.

I started by looking at module_surface_driver.F and can see quite clearly that under ...

CASE (NOAHMPSCHEME)
...
IF(SF_URBAN_PHYSICS > 0 ) THEN  !urban
...
call noahmp_urban (...) !<- run the subroutine in module_sf_noahmpdrv.F
...
IF((SF_URBAN_PHYSICS.eq.2).OR.(SF_URBAN_PHYSICS.eq.3)) THEN
           DO j=j_start(ij),j_end(ij)                             !urban
             DO i=i_start(ij),i_end(ij)                           !urban
                IF( IVGTYP(I,J) == ISURBAN    .or. IVGTYP(I,J) == LCZ_1 .or. IVGTYP(I,J) == LCZ_2 .or. &
                    IVGTYP(I,J) == LCZ_3      .or. IVGTYP(I,J) == LCZ_4 .or. IVGTYP(I,J) == LCZ_5 .or. &
                    IVGTYP(I,J) == LCZ_6      .or. IVGTYP(I,J) == LCZ_7 .or. IVGTYP(I,J) == LCZ_8 .or. &
                    IVGTYP(I,J) == LCZ_9      .or. IVGTYP(I,J) == LCZ_10 .or. IVGTYP(I,J) == LCZ_11 )THEN
                T2(I,J)   = TH_PHY(i,1,j)/((1.E5/PSFC(I,J))**RCP) !urban <-------------------------------------------------------------HERE
                TH2(I,J)  = TH_PHY(i,1,j) !urban
                Q2(I,J)   = qv_curr(i,1,j)  !urban
                U10(I,J)  = U_phy(I,1,J)                       !urban
                V10(I,J)  = V_phy(I,1,J)                       !urban
               END IF                                             !urban
             ENDDO                                                !urban
           ENDDO                                                  !urban
         ENDIF

it appears to be grabbing the TH_PHY variable at the first level, which is likely T2 with BEP impacts already taken into account? Same with U10, Q2, etc.

So then, look at noahmp_urban under module_sf_noahmpdrv.F I see ...

IF (SF_URBAN_PHYSICS == 2) THEN
...
  CALL BEP(...)
...
IF((SF_URBAN_PHYSICS == 2).OR.(SF_URBAN_PHYSICS == 3))THEN
...
      b_t_bep(i,k,j) = b_t_bep(i,k,j)*frc_urb2d(i,j) <-the explicit and explicit sources from BEP multiplied by urban factions which make sense
...
    b_t_bep(i,1,j)   = (1.-frc_urb2d(i,j))*hfx_rural(i,j)/dz8w(i,1,j)/rho(i,1,j)/CP+ & <-which is then modified the lowest cell by the rural heat flux in a mosaic fashion
                           b_t_bep(i,1,j)

So, my question is, where or how are these explicit and implicit parts incorporated into WRF-LES? From what I can tell, they are then used in the module_pbl_driver.F for the portions written by Alberto many moons ago.

IF ( idiff.eq.1 ) THEN 
...
b_t(i,k,j)=b_t_bep(i,k,j)

Later, in module_pbl_driver.F, they are used in

SUBROUTINE diff3d(...)

But WRF-LES uses no PBL scheme, so how are these impacts incorporated?

It is likely that I am missing something somewhere or that these impacts were never coupled to WRF-LES (which seems very unlikely). If anyone can point me towards where the magic is happening, it would be most appreciated and save me time!

 

[Ming Chen]

WRF-LES is designed for ideal run, i.e., it is not supposed to run with activated land surface scheme.
Are you trying to run WRF in LES mode over urban areas?

 

[jphorne]

Is that true? A large body of literature uses WRF-LES for real situations. While it has the capability, I have never seen it said anywhere that it was explicitly designed for idealized simulations. I have run WRF in LES mode successfully over urban areas, and much of the existing source code works fine with WRF in LES mode.

So, you are saying that aspects of the BEP/BEM models have not been specifically coupled to WRF-LES capabilities, which is why I cannot locate the code. Is this the case for other model options?

 

[Ming Chen]

I guess you mean you run real-data case with high resolutions that are appropriate for LES simulation. Let me know if I am wrong. For such cases you can run with urban physics scheme. However, for ideal LES simulation, official WRF codes always run with urban schemes being turned off.