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wrf physics

  1. K

    I want to ask some questions about WRF-LES

    I want to ask you whether you need to use the idea command when you use the ndown command in the WRF-LES process? In addition, I want to seek some tutorials about WRF-LES Thank you very much!
  2. O

    Fine vertical resolution, excluding unneeded WRF-output files, resetting snowfall and snow coverage to 0 before each integration

    Dear colleagues, (1). Please, how can I ensure that my simulation has a fine vertical resolution? (Vertical height above the ground). The e_vert? (2). How can I ensure that the values of snowfall and snow coverage are reset to 0 before each integration? (3). How do I exclude un-needed...
  3. P

    Underestimated CLDFRA in 4.4.1 compared to 4.3.1

    Hi All, Significant differences were found in the SWDOWN calculation between WRF-4.3.1 and WRF-4.4.1. Compared with measured radiation data, WRF-4.4.1 shows much worse scores. Similar differences are in CLDFRA: compared to satellite observation WRF-4.4.1 underestimates the values of the...
  4. L

    Calculation of T2 and the energy budget

    Hi all, Based on the relies on this link: WRF energy and moisture budget?, I know the energy balance calculation is: (1-ALBEDO)*SWDOWN+EMISS*(GLW-STBOLT*TSK**4)+GRDFLX-HFX-LH I am not sure how WRF calculates T2, I am curious about which component's change in the energy budget explains my T2...
  5. J

    Anyone knows how to use wrf-les?

    Hello everyone, I want to know if you have a relatively complete WRF-LeS tutorial. Or is it better to apply to LES? I found a lot of documents, but there is no specific setting. I am a novice, so I need some hand-to-hand solutions. If it can have a namelist reference, it is even better. It needs...
  6. S

    Frost depth information from wrf simulation

    Hi there, How do I calculate frost information from wrf simulation?
  7. O


    Dear colleagues, I came accross this (the attached picture) in the Noah-Mp technical note documentation can anyone explain the extra terms for the Lagv? Thank you for your help in advance.!
  8. W

    how to output energy consumption and carbon emissions from BEM

    I understand that it is possible to output carbon emissions, energy consumption (including electricity, gas, water, etc.) from the WRF BEM result, like set up the parameters of bldg_physics, but I cannot set the output parameters in namelist.input and correctly run real.exe. Is it because using...
  9. S

    Urban canopy options

    Hello, I run simulations to identify urban effects on cyclone precipitation. I'm working with ERA-5 input data and NLCD 2011 LULC data. My question is, if I keep the urban canopy option turned off (sf_urban_physics = 0), is it considering that there is no urban area and thus excluding the urban...
  10. H

    variables of SLAB land surface scheme

    Hello, I'm working on understand how SLAB land surface scheme calculate TSK(surface skin temperature). After reading module_sf_slab.F, I found the equations are TSKX=TG0(I)+DELTSM*DTHGDT(I) !-- DELTSM time step (second); DTHGDT(I)=(RNET(I)-QS(I))/CAPG(I)-HM(I)...
  11. M

    How to horizontally average a variable (RTHRATEN) filed in a WRF mpirun?

    Hi guys, I have been working on idealized cases using WRF-ARW V4.4.2. I try to average the temperature tendency caused by radiative heating at each level and at each time step (RRTMG scheme is used), but it seems rather difficult in a mpirun since the calculation is divided into many tiles and...
  12. M


    Does anyone have a step by step guide on running WRF with the Urban model turned on? I will appreciate. Thanks
  13. S

    WRF rain evaporation

    Hello everyone, I would like to know if anybody has tried switching off the rain evaporation in WRF within the boundary layer. I came across an older thread that mentioned the use of no_mp_heating option. But I specifically need to switch off evaporation of liquid. Any leads in this direction...
  14. C

    why the remaining energy item in energy budget is so large?

    Hi! I use Noah-MP land surface scheme to run WRF4.4 over Europe. Energy budget is usually expressed as Rnet = SH + LH + G, in which Rnet means net radiation flux, SH means sensible heat flux, LH means latent heat flux, and G means ground heat flux. The following pictures show the averages of...
  15. B

    About the usage of module_sf_exchcoef.F module in the momentum roughness calculation over water

    Hi all, I need information about the roughness scale calculations in the WRF model. Does the WRF model use the module_sf_exchcoef.F located in the physics directory while calculating the roughness length of the momentum and enthalpy fluxes? I have gone through the code and realized it would work...
  16. Y

    Noah-MP LSM model time step differentiation in WRF simulation

    I am using WRF V4.4 with Noah-MP. I would like to use WRF coupled to Noah-MP with a different timestep for NoahMP than the timestep specified for WRF in the namelist.input file. I used in the past the stand-alone Noah-MP model with external forcing and I could specify a time-step in the order...
  17. B

    isftcflx physics option to call znot_m_v8(uref, znotm) subroutine

    Hi all, I would like to know which isftcflx option (0,1, and 2) in the physics namelist would call the znot_m_v8 (uref, znotm) subroutine to calculate the aerodynamical roughness over water using 10m wind in the WRF v4.2.2. As per my understanding, if icoef_sf is equal to 8 then znot_wind10m...
  18. S

    How to save the contribution of subgrid mixing by prognostic TKE LES option on vertical velocity change?

    Dear scientists, Hello. I have a question. I want to analyze the budget of vertical velocity. I used LES PBL option (in a "seabreaze2d_x" idealized simulation) with prognostic TKE scheme (not smagorinsky) (I attached my namelist.input file). I thought the acceleration due to advection and the...
  19. B

    gwd_opt not working in WRFV4.3.2

    Hello everyone! When I run wrf.exe (Version 4.3.2) with gwd_opt equals to 3 in namelist.input, all the relevant diagnostic variables are zero, and the wind fields of all three domains (25km, 5km, and 1km)are exactly the same with gwd_opt equals to 0. According to the users' guide, gwd_opt...
  20. S

    How to Prescribe HFX, QFX, and LH in an idealized WRF simulation

    Dear WRF Community, I am trying to run a simulation to study the urban heat island problem. To do this, my plan is to run an idealized WRF simulation prescribing heating over a flat surface or a mountain. Any help would be highly appreciated. Thanks in advance. With Kind Regards Shak