Wrf eta levels to pressure. edu Wed Jan 8 08:53:17 MST 2020.

Wrf eta levels to pressure I would like to have very high vertical resolution (~ 100m) upto 3 km as I want to study the boundary layer. Using sfcprs3 to compute psfc d01 2019-07-19_00:00:00 You need one of four things: d01 2019-07-19_00:00:00 1) More eta levels: e_vert Hi, I have been trying to run the WRF model for 24 hours over a month (September 2018). There is a eta=>pressure that can be done. Previous message: [ncl-talk] Interpolate WRF eta levels to pressure levels Next message: [ncl-talk] Interpolate WRF eta levels to pressure levels Messages sorted by: I have been trying to interpolate from eta model level to presure levels with NCL but I have not been be able to suceed on this. All measures of moisture (Td, RH, r_v, q) are available at 2m, eta, and pressure levels. (model_config_rec%eta_levels(1) . However, the Python script from this post might serve as an example of how you could interpolate a field to a single isobaric level. I follow your question to see the Hi: I am making a WRF4. /link_grib. sdahal New member. If you stretched your vertical grid with dense-enough sigma levels near the surface you can interpolate any 3D parameter to Hello, I am new to using xWRF, and have been following the vertical interpolation example provided in the documentation to learn how to convert the native WRF sigma or Eta levels into a different coordinate system. 3, 2. g. So that, I can plot >>>>> a vertical cross section of WRF reflectivity for various longitude >>>>> corresponding to a single latitude. [ncl-talk] Interpolate WRF eta levels to pressure levels Dennis Shea shea at ucar. The surface pressure is passed through the smoothing d01 2019-07-19_00:00:00 Turning off use of TROPOPAUSE level data in vertical interpolation Max map factor in domain 1 = 1. i need suggestion how >>>>> I can convert eta level to pressure level/Height level. You can tell where by looking at the WRF registry or the attributes of NetCDF files, which WRF uses as I/O format. 88 in your example) that is dictated by the p_top_requested variable, and the maximum is always 1. For example, in the following lines I have made the settings for 39 levels. pressure_sfc (pint. This message: [ Message body] [ More options] getting height levels and terrian height levels from the file z = wrf_user_getvar(a, "z",-1) ; grid point height dimz = dimsizes(z) ; get the dimensions If not, I will try to play with UPP, but I am not sure on which Vtable I have to use: in particular, Vtable. NCL and Python both have the capability of vertical interpolation. I checked the Registry. If simulations are conducted over areas with little-to-no terrain, then I'd advise you to write your own code and use the following to convert to Z(km Parameters: field3d (xarray. ARWpost runs successfully. Previous message: pressure levels and dump the data in NETCDF format. Variables in the vertical can be selected with the WRF eta vertical levels or using pressure levels; Some of the variables From the WRF ARW technical guide it appears that the formula for eta level is (p - p_top) / (p_surface - p_top). Staff member. If you have WRF data, then we recommend that you use the wrf_user_intrp3d function instead (see example 2 below). My study will primarily be focused on storms and the boundary layer, so ideally, I would like to have very high This function interpolates a WRF-ARW variable to a horizontal plane at the specified vertical level, which can be in height or pressure coordinates. If you set pmin = 1000, then you will get 29 pressure levels. My forcing data are FNL 1deg x 1deg and I use 100 processors. ndarray) – A three-dimensional array for the vertical coordinate, typically pressure or height. 0000000 50. I am working WRF outputl file and require to extract wind and temp values at 850 hPa, 700 hPa and 500 hPa pressure levels. When I use Grads and open the file it prints "LEV set to 1 1" and if I execute it, it prints "zdef 27 linear 1 1". mahoba_at_nyahnyahspammersnyahnyah> Date: Wed Mar 28 2012 - 06:35:48 MDT. You can explicitly specify eta_levels in namelist by setting I am trying to set up WRF model and I would like to specify explicit eta levels. ARWp. "; Next in thread: Mary Haley: "Re: change eta levels to pressure levels in cross-section plot with the function "gsn_csm_pres_hgt_vector""; Reply: Mary Haley: "Re: Parameters: wrfin (netCDF4. 1 in order to avoid the skipping of pressure levels near the top. 954, 0. Added wind direction (earth) and wind speed at 2m, eta, and pressure levels. It sees that you have those defined, and you only have 36 levels listed, but are setting e_vert = 65, which is why you are getting the error: First eta level should be 1. Code taken directly from ripdp_wrfarw. csh or ungrib. The code I've used can be found here The data for this example comes from the outer domain of a WRF-ARW model forecast initialized at 1200 UTC on 03 June 1980. In the namelist. Does anyone have suggestions about Grid. This function combined with wrf_user_vert_cross replaces wrf_user_intrp3d , which This provides flexibility to control the file sizes of WRF data. 2 simulation up to 1 hPa and I am trying to modify the zap_close_levels default value to 0. 0"; Previous message: Mary Haley: "Re: I have a question about csa2ld function. The scheme includes parameterizations of a viscous Hi Nikhil, Forcing WRF with model level data is possible and often done - for example for the ECMWF operational forecasts with 138 hybrid levels nowadays. input, I can check the generated eta levels and their height, thickness information in the real log file rsl. Previous message: [ncl-talk] Interpolate WRF eta levels to pressure levels Next message: [ncl-talk] Interpolate WRF eta levels to pressure levels Messages sorted by: Calculate pressure from sigma values. Determine the model top pressure. 6 code and put those levels in the namelist for the v4 (and after) WRF-system pre-processor (real) and the model (WRF). 1) and a pressure coordinate at upper levels (based on 2. Previous message: [ncl-talk] Interpolate WRF eta levels to pressure levels Next message: [ncl-talk] Interpolate WRF eta levels to pressure levels Messages sorted by: Then you can manually increase the number of levels based on the automatically generated eta levels by REAL. and are far more familiar with the WRF eta level coordinate system. 0 now, with the hybrid vertical coordinate, I want to use the pressure in each level (p+pb) and the eta value of the boundary of each level(ZNW) to calculate the boundary pressures of each layer. "mu" fields still retain the meaning of column pressure, but the definition of . edu Wed Jan 8 11:31:25 MST 2020. This is the raw computational algorithm and does not extract any variables from WRF output files. Model data courtesy Matthew Wilson, Valparaiso University Department of Geography and Meteorology. NioFile or an iterable sequence of the aforementioned types. 99 , 0. PyNGL (Python NCL Graphics Library) is a python interface with the same core graphics as NCL (NCAR Command Language) for visualization and data processing. 909, 0. , don't set eta_levels. CALL wrf_debug(0, "nest_init_utils: eta_levels are not WRF Users' Guide in restructured text format. Weather Research and Forecasting (WRF) Model. Is there a recommended value for the first layer of CMAQ model? Or, is there any value that is not recommended to use? I searched in several articles for the first height adopted for the models, but most articles only report the amount of Eta levels used. A different type of plot is created for each level, using wrf_contour, wrf_vector, and wrf_map_overlays. Dec 4, 2024 #15 William. I am using three two way nested domains (9km, 3km and 1km) with 63 explicitly defined vertical levels over a Setting Model Vertical Levels Eta levels are automatically computed by the real program, based on the number of levels set by the namelist option “e_vert. I am unable to find which eta level corresponds to which pressure level. The WRF model is used as a regional climate model to downscale outputs from the CCSM3 global climate model forced by the A1B future emissions scenario from IPCC-AR4. Quantity – Pressure values at the given sigma levels. getvar() to both extract and compute diagnostic variables. 13 -14. ; field (xarray. The surface level has a value of 1, and the top level has a value of 0. the function vintp2p_ecmwf should work fine for WRF data. UPP is for WRF-ARW output that has been processed on eta/sigma levels, while Vtable. ” However, full eta levels may be explicitely defined with the namelist option “eta_levels. Interpolate from model levels to pressure levels Interpolate to one pressure level. A better question for this is "what is the stretching rate I need to use?" See Setting Model Vertical Levels in the WRF Users' Guide. I want to know how ete to pressure conversion take place. r. ----- ERROR: The reference pressure is not monotonically decreasing This tends to be caused by very high topography (i,j) = 1 1 , topography = 1132. L. Previous message: [ncl-talk] Interpolate WRF eta levels to pressure levels Next message: [ncl-talk] Interpolate WRF eta levels to pressure levels Messages sorted by: The sigma vertical coordinate system is a dimensionless coordinate system used in atmospheric models like WRF. Here I have added a 1) Try to just use the model levels that are provided by WRF. -1. Valid strings are: Based on the automatically generated eta levels, you can add extra levels in lower atmosphere. input. The entire category can be selected and the selected variables within that category will be included in the CF file. Since pressure will vary at the surface, both horizontally and temporally, then the sigma value of 1 will be your surface level (versus the model top, with the sigma value of 0, which will usually be a fixed pressure). ARW. 934, 0. Prototype function wrf_slp ( Z : numeric, T : numeric, P : numeric, Q : numeric ) return_val [dimsizes(Z)] : float or double Arguments Z. ndarray) – Sigma levels to be converted to pressure levels. DO k=1,kde_n. ncl to fit ou needs. edu> wrote: > Hi all, > > Is there any function/command in NCL to convert WRF eta levels to pressure > levels? Calculates sea level pressure from ARW WRF model output. Layer between two levels at specified pressure differences from ground to level : Pressure difference from ground to top level in hPa : Pressure difference from ground to bottom level in hPa : 117 : Potential vorticity surface : 109 K m2 kg1 s1 : 118 : Reserved : 119 : ETA* level : ETA value in 1/10000 (2 octets) 120 : Layer between two ETA* levels How to convert eta level to pressure level in WRF model I am working WRF outputl file and require to extract wind and temp values at 850 hPa, 700 hPa and 500 hPa pressure levels. Variables are grouped by category. for ncl, you should check out ncl Could you tell me what the WRF's vertical coordinate system is? Sigma or eta? According to the User WRF Guide document, uses a terrain-following hydrostatic pressure Perhaps, you could convert to pressure levels and modify the wrf_meteo5. Grids in WRF are logically rectilinear. Scale the dt in the model accordingly. fierro at gmail. [ncl-talk] Interpolate WRF eta levels to pressure levels Anahita Amiri Farahani aamir003 at ucr. The data is interpolated from the irregular pressure values for each sigma level to the new input mandatory isobaric Hi, I'm also in a similar situation (studying wind turbines below 200m). ndarray) – A three-dimensional field. Geopotential height in [m] with at least 3 dimensions. DataArray or numpy. Previous message: [ncl-talk] Interpolate This function interpolates terrain following data to either a given pressure or height level. edu Wed Jan 8 14:44:11 MST 2020. As the WRF vertical coordinates are based on eta level, I am having trouble In the namelist_ERA5_1000. edu Wed Jan 8 11:48:20 MST 2020. It also does an extrapolation below ground level and above the model surfaces. slp¶ wrf. This has involved the use of the wrf_user_intrp3d() function to interpolate height fields at 19 different pressure levels. A good procedure to follow may be: 1. Determine how thick your lowest layer is (50 m by default) 3. How do I decide the number of vertical levels to use? And, how do I decide the eta levels manually [ncl-talk] Interpolate WRF eta levels to pressure levels Dennis Shea shea at ucar. mcmillen@utah. Good luck. Although the example provided in the documentation does this for the pressure coordinate, I would like to do this for the height (z) coordinate. Abstract Although a terrain-following vertical coordinate is well suited for the application of surface boundary conditions, it is well known that the influences of the terrain on the coordinate surfaces can contribute to increase numerical errors, particularly over steep topography. I. 97, 0. If these steps are successful, then you should see the FILE:** files which When your initial data level is different with WRF, in Vtable file you can deal with variables that have one level. Notes and solutions. ncl? > > Thanks Jonathan > > Jonathan Wynn Smith > From WRF output, you have elevation and pressure for each sigma level. Ming Chen, you suggest running REAL first to create eta levels, which to my understanding, is required to get the minimum eta level (0. Take a look at the On Tue, Jan 7, 2020 at 9:12 AM Anahita Amiri Farahani via ncl-talk < ncl-talk at ucar. 88,. isobaric. 2. edu Wed Jan 8 08:53:17 MST 2020. eta = (pressure_level - pressure_t op) /(pressure_surface - pressure_top) 31 Y ou may find the “ZWN” variable in the WRF output files to retrieve the pressure of each From: <jwsmith_at_nyahnyahspammersnyahnyah> Date: Thu Jan 14 2010 - 05:15:35 MST. It must be on the ARW WRF unstaggered grid. How can I specify eta_levels? Thread starter sdahal; Start date Dec 5, 2024; S. wrf_user_vert_interp is part of a library of functions and procedures in ! c3 and c4 to compute pressure with two reference pressures (nest%this_is_an_ideal_run) . 0 and the last 0. So, I suppose there’s something wrong in your step of . You can easily use the existing monotonic list of eta values from the v3. Obukhov, 1954). I am using three two way nested domains (9km, 3km and 1km) with 63 explicitly defined vertical levels over a Weather Research and Forecast (WRF) model exploratory sensitivity simulations were performed to determine the impact of vertical grid resolution (VGR) on the forecast skill of Midwest summer rainfall. 2, 2. t eta level only. Added winds rotated to true earth coordinates at 2m, eta, and pressure levels. Mr. A string indicating the vertical coordinate type to interpolate to. ; desiredlev (float, 1D wrf. 4. I added a new variable with cdo, height (z), where [ncl-talk] Interpolate WRF eta levels to pressure levels Anahita Amiri Farahani aamir003 at ucr. com Thu May 22 13:11:14 MDT 2014. You cannot specify WRF eta levels to specific height levels like 10m, 25m, 50m, etc. 00000 , 0. eg > How do I change eta levels to pressure levels in teh WRF Example > script entitled wrf_meteo5. out. The AGL (Above Ground Level) of the same eta level varied slightly during simulation This message: [ Message body]; Next message: David Brown: "Re: gsn_add_polyline not working in 6. ncl? Thanks Jonathan The p top variable determines the simulation's top pressure level. Josh New member. d(p_dry))/d(eta) has I am trying to set up WRF model and I would like to specify explicit eta levels. However, the only data I have been given are the model heights (e. or, maybe, the output could be used for something like. Examples "pressure", "pres" - pressure [hPa] "ght_msl" - grid point height msl [km] "ght_agl" - grid point height agl [km] AGL, Height MSL, Potential Temperature and Equivalent Potential Temperature. Re: change eta levels to pressure levels in cross-section plot with the function "gsn_csm_pres_hgt_vector" This message: [ Message body] [ More options] ; Related messages: [ Next message] [ Previous message] [ In reply to] I am running WRF model with three two-way nested domains of 9,3 an 1km resolutions. It's conceivable that this value was modified in the input file but that the namelist file was not updated to reflect the change. 97 , 0. hyb_coord file and knew that the new equation is You can also use the new namelist option pmin (unit Pa) for ungrib to limit the pressure level data ungrib processes. If your model top goes higher, for example p_top = 1hPa, you will need to increase e_vert to 61 or more. 1) The vertical coordinate used in WRF is a blending of a sigma coordinate, η, based on dry pressures, at lower levels (Skamarock, 2. 81 for geopotential height at full level. Best regards, the eta might or might not correspond exactly to your desired pressure levels, if you want to get the data, you have to use "ncl" or "wrf_interp". slp (height, tkel, pres, qv, meta=True, units='hPa') ¶ Return the sea level pressure. Variables for WRF cell indexed (i,j,k) can be located at one of 4 possible points. o. 02. To reduce these errors, a hybrid sigma–pressure coordinate is formulated in the The GHT is interpolated to mass levels using the eta values on half mass levels(ZNU) and eta values on full (w) levels (ZNW) variable. exe. The model levels are not at constant pressure or height surfaces because they follow terrain. Can anyone guide me in correct direction. 1 or 1 WRF wrf_interp_4. The vertical distributions of sigma levels in L37 and L50 are illustrated in Fig. ndarray) – A three-dimensional field to interpolate, with the rightmost dimensions of nz x ny x nx. There might not exist a 'k' level that is exactly located at 400 hPa. ; vert (xarray. Ming Chen Moderator. You can also tell by the fact that staggered variables have the staggered dimension larger by one, since there needs to be Interpolation of WRF data from pressure levels to height levels. Previous message: [ncl-talk] Interpolate WRF eta levels to pressure levels Next message: [ncl-talk] Fwd: Line Thickness of outline map Messages sorted by: Jose, The model sigma levels are there to distribute your model levels between the model top and the surface. Two-way nesting Can cause weird feedback patterns near domain boundaries. Thereby, nudging at levels exactly above 400hPa may not be feasible. 2) Are you running multiple different tests, with different dates? Then met_em*-files will not have the correct pressure data. % Script to calculate eta level values from z height values to specify WRF % model levels. input file (where you are letting the model choose the levels), you need to remove the eta_levels from the namelist file. (check page 5-79 of WRF-ARW Manual). level 1 = 37m; level 2 = 112m; level 74 = 33,000m). Use wrf. NioFile, or an iterable) – WRF-ARW NetCDF data as a netCDF4. Is entering pre-determined eta levels, which go resolutions: one uses 37 vertical levels (L37) and the other uses 50 vertical levels (L50). (Note: I've modified the title of this thread to indicate that the question is one of interpolation to pressure levels. At the lowest model layer everything looks normal but all layers above that simply have the inverse level number as pressure; this causes all kinds of weird behaviour in WRF, especially for the vertical wind. The model top-level pressure for both cases is set at 50 hPa. What about if I would want to provide WRF with the pressure level wind speeds, and the 10 meter and 100 meter single level data. Hatheway said: **Guide to Using Copernicus ERA5 Data with WRF** c. Therefore, the VGLVLS attribute in the METCRO3D files (or other EQUATES 3D files) do NOT allow you to compute pressure levels at the layer interfaces using surface pressure and the pressure at the top (ptop), as one could have done if the older terrain-following “sigma” From: Abhishek Gupta <abhi. AAA &mldr;&mldr;) and logs (ungrib. Is there a way to convert these model heights into eta levels? Thank you for your help! [Wrf-users] Transforming eta levels to p levels Alex Fierro alexandre. To whome this may concern, How do I change eta levels to pressure levels in teh WRF Example script entitled wrf_meteo5. edu Tue Jan 7 09:12:08 MST 2020. input to obtain the common variables at pressure or vertical levels. f. . ARWpost option "0" is marked in "interp_method". % 28 Jan 2014 % John D McMillen % john. Dec 5, 2024 [ncl-talk] Interpolate WRF eta levels to pressure levels Anahita Amiri Farahani aamir003 at ucr. I in WRF. Here 'k' refers to the eta levels of WRF. They are 28 levels. 5). Previous message: [ncl-talk] Interpolate WRF eta levels to pressure levels Next message: [ncl-talk] Interpolate WRF eta levels to pressure levels Messages sorted by: Hi there, I am using WRF4. 0 in WRF? I will appreciate your reply. Quantity) – Pressure value at the top of the model domain. edu Wed Jan 8 08:53:39 MST 2020. 2. This results in some nice titles above each plot and an informational label below each plot. Dec 5, 2024 #1 When the REAL run is complete, where should I look for the automatically generated eta_levels? Thank you!? M. 98169 m Hi, I have been trying to run the WRF model for 24 hours over a month (September 2018). Contribute to wrf-model/Users_Guide development by creating an account on GitHub. My questions are: 1] Does the model height locate in the middle of two eta_levels in WRF? For example, is the first model height in the middle of the eta_level 1 and the eta_level 2? 2] Is the ground surface defined as eta_level = 1. Here comes the problem. 0000000 0. edu Wed Jan 8 09:05:58 MST 2020. ncl: This script uses wrf_user_interp_level to extract a horizontal slice from several 3D WRF fields at four different pressure levels. Returns: pint. WRF uses a hybrid pressure coordinate system eta = (Ph - Pht)/(Phs - Pht) with Ph the hydrostatic pressure, and Pht and Phs the values at the topmost and surface levels respectively It looks like etac is the "critical eta level" or the eta level at which the WRF model surfaces become completely isobaric. Setting this value is not intuitive, and a reasonable value that . I don't know about variables with many levels. When I tried to modify the value to 0. 0000 as such: using new automatic levels program 1 50. 0 in namelist Hi Yasmin, I’ve used the ERA5 pressure level data several times and it always works well. Is it possible? Does anyone have any thoughts on this? J. The pressure at each level is calculated based on the surface pressure and the specified Hello, I'm using NCL to create a netCDF file with height data at pressure levels as opposed to eta levels. Please take a look at the documents; There is an option in WRF namelist. This array must have the same dimensionality as field3d. WRF Model . 95 , . The new interpolated eta levels may be rational as they are generated based on the default eta levels of WRF. lirui111 New member Vertical interpolation is required to put wrfout data from eta levels to either pressure level or height level. Next message: [ncl-talk] Interpolate WRF eta levels to pressure levels Messages sorted by:. Parameters: sigma (numpy. I am sure that some formula must Hi, If I don't define e_vert in the namelist. 4, 2. For example , suppose you run REAL and get the following eta levels: eta_levels = 1, 0. e_vert = 39, 39, 39, Dear Pascal, In your WRF output there are a pair of variables called P and PB, Total pressure in mb (=hPa) = (P + PB) * 0. exe for this test. ” The number of levels must agree with the number of eta surfaces allocated (e_vert). You can customize the vertical levels with "eta_levels" in WRF namelist (namelist. I want pressure level to calculate precipitable water in WRF output -- Abhishek Kumar Gupta, Junior Research Fellow, India Meteorological Department, Lodi Road ,New Delhi-110003, India Download Table | Pressure and Eta levels at some points above the surface useful for interpre- tation of Figs. Just let the model choose for you. A better idea would be as you suggest - just use the same eta levels from your previous TF simulations and rerun the new version of the real program. Varying the VGR indicated that a refined VGR, while adopting the widely used North America Regional Reanalysis (NARR) for initial and lateral boundary conditions, Hi all, I have some concerns about the vertical resolution of CMAQ. Previous message: [ncl-talk] CSV file plotting issue. 0. In this system, the vertical levels are defined as fractions of pressure. Surface Boundary Layer: The atmospheric surface layer is the lowest part of the atmospheric boundary layer (typically about a tenth of the height of the BL ) where mechanical The Eta surface layer scheme (Janjic, 1996, 2002) is based on similarity theory (Monin and. edu Wed Jan 8 08:31:49 MST 2020. There isn't at present any "officially supported" tool for interpolating MPAS-Atmosphere output to pressure levels. 0000000 user to select the eta level at which the WRF model surfaces become completely . log) related to these two command. Dataset, Nio. WRF Vertical Coordinates. 01. 1, in which the corresponding pressure level is calculated assuming a surface pressure of 1000 hPa. 993814707 2 64. edu % This script will calculate eta values at w grid points for WRF model % levels when given the model top pressure and the vertical distribution % of model level w grid points in height, z. 993, 0. This is because WRF implements hybrid vertical coordinate, which is roughly terrain I have some doubts about " the height of model level" in WRF. Determine maximum [ncl-talk] Interpolate WRF eta levels to pressure levels Anahita Amiri Farahani aamir003 at ucr. It usually should be larger than 40 with p_top = 50 hPa. ESS 5010 C: An introduction to the Weather Research and Forecasting model (WRF) Assignment # 1, Due 2 October. ) The WRF simulations performed for EQUATES used the hybrid vertical coordinate system. e. 98 , 0. 01 for pressure at half-sigma level, and (PH + PHB)/9. I have a WRF output file in which the sigma levels are indicated by the eta_levels option of the namelist. UPP is suited for output that has been processed by UPP and is on pressure levels. You need to check files (GRIBFILE. If the test runs okay then you know it's your specific eta levels causing the problem. pressure_top (pint. / You can then replace the first several eta levels by: They can be computed from: (P + PB)*0. Cite Hi, e_vert can be specified based on your case. input). You'll need to re-run real. Quantity) – Surface pressure value. For example, suppose REAL produces the following eta levels: eta_levels = 1. #2 Julius, If you are familiar with NCL, then it is the best option you can use to put data from model level to pressure level. 0)) THEN!DJW If we're running an ideal case and do not have levels set in the!namelist then we set znw using constant spacing in eta. ; vert_coord (str) – . EQ. The default value is 0. 983, 0. My study will primarily be focused on storms and the boundary layer, so ideally, I would like to have very high Now I am trying to plot upper air winds at 925, 950, 850, 700, 500, 300 and 200 hPa. As the WRF vertical coordinates are based on eta level, I am having troubl I have WRF output in native model grid (eta levels) and the variables pressure, geopotential height (among other obviously). ) from publication: Feasibility Study of Integration of Mesoscale Meteorology Therefore whenever I generated plot, it always >>>>> provide vertical cross section w. AND. qmvrw duanz uevphe bxly dpgvcjw qfpqto smxtc msosn ydsw xjouy