Science method

WRF - Science method

Explore the latest questions and answers in WRF, and find WRF experts.
Questions related to WRF
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I have a 5-day nc file as a result of a WR model run.
1.- I need to extract data for a specific point (latitude and longitude) but I have tried it and it gives me the values for a node of the mesh.
How can I get that data?
2.- How can I make a precipitation map for each of the days considering convective and non-convective precipitation (RAINC and RAINNC) ?
File: wrfout_d01_2022-07-13_00_00_00
I hope you can advise me
Thank you
Regards.
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Hi,
I found wrf-python very useful (https://wrf-python.readthedocs.io/en/latest/) . The package is well documented and there are many examples of how plotting WRF results. I used to do my plots with ncl and GrADS but now, wrf-python is my way to go!
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Hi,
I am looking for examples of the use of AZURE cloud for doing WRF simulation. Do you use containers such as Docker or upload the model with a script each time?
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Dear Prof. Héctor Hito Sepúlveda,
Useful info is presented below in the following sources:
Run container applications on Azure Batch
Why use containers? Using containers provides an easy way to run Batch tasks without having to manage an environment and dependencies to run applications. Containers deploy applications as lightweight, portable, self-sufficient units that can run in several different environments. For example, build and test a container locally, then upload the container image to a registry in Azure or elsewhere. ... For Windows container workloads, we recommend choosing a multicore VM size for your pool. Supported virtual machine images. ... Use the application packages feature of Azure Batch to easily manage multiple applications and versions for installation on Batch compute nodes. Run tasks concurrently to maximize usage of Batch compute nodes
_____
[Huawei Cloud Technology Sharing] Weather simulation WRF containerized operation practice
WRF stands for Weather Research and Forecasting Model, which is a software for weather research and forecasting models. Let's use Docker containerization to take one, which is convenient to use. 1 Introduction to WRF. The full name of WRF is Weather Research and Forecasting Model, which is a weather-research and forecasting model that can be used for fine-scale weather simulation and forecasting. reference: https://xg1990.com/blog/archives/190. ... Therefore, using Docker lightweight containers to ensure the consistency of the software environment is a very inconsistent way. Once the mirroring is done, WRF can be run anywhere. This can also be seen from the official WRF GitHub website.
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Is there a variable with SST forecast up to 45 days ahead to initialize the WRF separately?
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Sorry for the format ... please check here to have a more beautiful table:
NOTE: The Vtable is for the CFS Reanalyses, but should work also for (sub)seasonal forecats. Just check carefully if the WPS works fine and gives no errors.
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Hi,
I would like to initialize WRF over Indian region using NCEP reanalysis data. I haven't been able to find a user guide explaining the how to. I am not sure which dataset(s) I am supposed to download or what the steps are for this process.
Kindly help me out.
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But I am actually trying to use NCEP reanalysis data for initialization and not GFS forecast. Would you happen to have any insight on that?
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While running the "real" program in WRF I am getting error as shown here, please suggest me the solution. Also I am atttaching namelist files with screenshot. Suggest me solution ?
[shantij@master1 run]$ mpirun -np 1 ./real.exe
starting wrf task 0 of 1
[shantij@master1 run]$ tail rsl.error.0000
----- ERROR: The reference pressure is not monotonically decreasing
This tends to be caused by very high topography
(i,j) = 46 26 , topography = 6756.41504 m
k = 5 , reference pressure = 38784.3516 Pa
k = 6 , reference pressure = 38813.1172 Pa
-------------- FATAL CALLED ---------------
FATAL CALLED FROM FILE: <stdin> LINE: 1236
In the dynamics namelist record, reduce etac from 0.200000003
-------------------------------------------
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
[shantij@master1 run] $
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(I saw your namelist.input, in which time steps are too high. it must be 4*dx (in km) to 6*dx.). you can check on the link below. Try the solution provided there. for the issue you wrote.
Regards
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I have registered for conference well held in Singapore from 9-10 September 2019 
I want to ask if this event is a real event.
Name of event: International Conference on Applied Mathematics and Science (ICAMS-19) 
Organization: WRF CONFERENCE 
Date: 9th-10th SEP 2019
Best regards
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Hello Usama,
I would not spend any time looking at that 'conference'.
I quote from that page,
"The main focus of conference is to improve the , accelerate the translation of leading edge discovery at research level"
Ungrammatical, misspelled.
But the main issue I have with it, is that there is no topic.
What on Earth is this conference about?
An event so broad in scope cannot hope to be useful in attracting an audience that would actually be beneficial to its attendees.
The link to "Upcoming conference" does not work. The telephone number is a British one (+44) but the Whats App number is not.
If you can tell me your field of interest, I might be able to suggest some useful meetings. My background is in aerospace systems, material testing for oil & gas firms, and respiratory medical devices.
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I'm making a nested, high resolution simulation (~300m*300m) of WRF in the polar region. The existing static sea ice data is of low resolution and I want to update this static data with a satellite based high resolution data. I need to update the static field only for the inner domain.
How can I do it?
What are the best tools for the same?
Anything in particular I should be careful about?
Thank you in advance.
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Hi, you need to assimilate the high resolution satellite data into the initial field of WRF run.
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Hi,
I would like to run a few numerical experiments with WRF where I change some initial conditions, for eg. the wind shear and study the effects it has on the simulation of various atmospheric parameters. Could someone please guide me as to how I can go about doing that? How can I change certain initial conditions to study their effect on the simultion?
Thankyou.
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Hi, Vijayan Gv
When you run the WRF model, it will takes a few hours of "spin-up" time to ensure the stability of model integration. Thus, I'm not worried about the problem caused by changing a few values in the initial field. Of course you can use nudging to moderate the spin-up if necessary.
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I used to run the idealized simulations using idealized mountains. This time I am trying to use real topography instead of idealized topography. I haven't got any tutorial or resources to do this even in the WRF user guide. Any help would be highly appreciated. Thanks in advance.
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There would not have a standard run for an idealized atmosphere with a realistic topography, but you may replace the idealized terrain height with the realistic terrain height by modify the code. For idealized cases, there is no wrfinput file, otherwise you could just replace the terrain height in the file.
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I am trying to compare the rainfall data measured at several met station locations with the netCDF output from WRF. I can create tslist for exact locations matching the met-mast lat/lon and generate the single point TS files. However, I am not convinced this may be the optimal way for comparison considering the assumptions and approximations in the cumulus and microphysics models and there can be deviations of few cells. Any suggestions or references will be appreciated.
Thanks.
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Thanks for the detailed information Geoffrey.
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For graphical display of WRF output data, there is NCL script, but i have not found any working script for converting data to text or other readable format. there are some softwares but they are need activation for use.
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Hi ! Have you managed to convert the wrfout files to csv?
I have generated ctl file using ARWpost, but when I apply cdo -f nc import_binary output.ctl output.nc, I get an error related to pdef, present in ctl file.
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Hello,
I am a research assistant on hydrology and fluid dynamics, with a background in Civil Engineering, Currently, our research team have been working on evaluating Data Assimilation techniques for rainfall-runoff predictions.
I would like to know if you have suggestions of studies or books about data assimilation especially focused on the applications in hydrology and hydraulics. Are there any similar studies to recommend? Does anyone have a solved numerical example of rainfall-runoff predictions by means of data assimilation techniques?
Thank you in advance.
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You might look at some of the papers by Dr. Dong-Jun Seo. See:
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I have tried to test the P3 (MP = 50 and 51) scheme for Bangladesh. Simulations begin smoothly, but some time later it stops. There are no error messages shown anywhere. What could be the reason behind this?
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It could be a segmentation fault. You must provide your namelist.input and slurm files for more information. Also, you may visit the WRF Support Forum at http://forum.mmm.ucar.edu/phpBB3/ for possible solutions.
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I am looking for plotting the azimuthally averaged radius-height cross-section of simulated radial wind from WRF output.
If anyone knows how to do the same (or has a script), kindly share with me.
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Using NCL, you can easily plot radial wind from wrfout. If you know how to use NCL, the following script would be helpful.
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I plotted a zommed plot of the WRF outputs . but when I decided to add the station data values on this plot the location of the stations arebased on the original plot (not zoomed). this resulted in wrong position of stations.
I do appreciate if help me.
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may be this video can help you to love your problem
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I trying to generate initial and boundary conditions using ERA5 data while running real.exe in WRF model. However, it ended with error message
I have provided P_TOP_request=5000
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The value is correct, but without knowing the error message is difficult to help you.
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I am carrying out PBL parametrization sensitivity study. I am curious to know whether it is beneficial to carry out sensitivity study with WRF-Chem, or the results with WRF alone is sufficient.
My view is that WRF alone is sufficient, since the common part of advection-diffusion in both WRF and WRF-Chem will be same for the same PBL scheme.
Please give your views.
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Academic resources on atmospheric dispersion are provided on the project references:
SINGLE PHASE AND MULTIPHASE TURBULENT FLOWS (SMTF) IN NATURE AND ENGINEERING APPLICATIONS | Jamel Chahed | 3 publications | Research Project (researchgate.net)
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Hi,
I am trying to run WRF with three nested domains of resolutions 18km, 6km and 2km.
I need the extent of the outermost domain to be 80 degrees longitudinally, ie from east to west, and 55 degrees latitudinally.
Are there any constraints to be kept in mind while deciding the extents of the inner domains. For eg, should the extent be some ratio of the extent of the parent domain? For my case, since the domain ratio is 3, should my second domain have a longitudinal extent of at least 27 degrees?
Is there any constrain like that, or can we choose the sizes, ie, extents of our domains as per the location of our area of interest that we plan to study?
Are there any other things/ constraints/ rules we need to keep in mind while deciding the domain configuration?
Kindly help me out with these queries.
Thankyou!
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Vijayan Gv It is not mandatory to follow the same criteria but in case if you get an error try to do it Because the same error I have solved in minecase. https://meteo.unican.es/trac/wiki/WRF4GTutorial2
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Hi,
I am trying to optimize WRF namelist.input parameters in order to conduct a comparison with the observed data. So, I would like to know how to determine that eta level corresponds to a given height.
Thx
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Hi,
To calculate the altitude above sea level in meters I use this: height = (PH+PHB)/9.81 You can apply it for each level and determine the corresponding height.
Best,
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Hi,
I am trying to run genbe for a domain with 3km resolution. Gen be fails in stage 2a with error 24 :
---------------------------------------------------------------
Run Stage 2: Calculate regression coefficients.
---------------------------------------------------------------
Beginning CPU time: Thu Dec 9 12:55:52 IST 2021
Ending CPU time: Thu Dec 9 12:55:52 IST 2021
---------------------------------------------------------------
Run Stage 2a: Calculate control variable fields.
---------------------------------------------------------------
Beginning CPU time: Thu Dec 9 12:55:52 IST 2021
Stage 2a failed with error 24
Can someone help me understand what the error is and how I can rectify it?
Thankyou!
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Vijayan Gv what is the interval of your outfile? You have to generate it with 12 hours interval.
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Dear all members,
I am studying about WRF to compute weather's parameters.
So, I consider affording a reasonable-priced device so I can install WRF and explore it - as a NEWBIE!
I have questions like:
1/ Can WRF be installed on CentOS 7. I prefer CentOS to other kinds of Linux (like Mint, Ubuntu, RedHat or something like that)
2/ A mobile workstation (like Dell Precision 7510, 7710 with Xeon-cpu inside - JUST 4 CORES COMMONLY ) could run WRF model well, couldn't it. Actually, a MOBILE workstation like that has a powerful CPU inside. But I'm confused by the number of CORES, i think it should have some cores more for better performance.
(I would study on WRF 4.0 and later version, domain for about 200*200 for a specific region like a state of America [U.S.])
I really appreciate your help! Thanks for all!
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Of course, you can run WRF on a laptop but with minimum requirement.
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Hi there all,
I am trying to put an eqn into the WRF Chem. In the module module_input_tracer; its like
my_tracer(...)=my_tracer(...)*(0.5**0.973)
it takes values between 10^-31 to 10^36
Any idea to solve it ?
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thanks; but it is not the right way
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Hi,
I have problem to choose i_parent_start and j_parent_start values in order to get the most inner domain to surround a given area/zone with wanted dimension (e.g: 10km*10km).
I want to compare collected data and that simulated using WRF.
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Hi every one,
I would like to ask you how to chose parameters/values in namelist.input for a given zone (e.g: tropical zone such as sub-equatorial African region). I attach my namelist file I am trying to use now.
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Dear all,
I am trying to run WRF-Chem for the first time. I have been running WRF for several years now.
I have monthly CAMS global data, and I have no idea how to prepare these files to go into WRF-Chem.
I have a file called prep_sources_chem.inp but I am not sure if it's the right one to use.
Any help is much appreciated.
Many Thanks
Joana
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I found the following web site:
How to run the WRF-Chem model using CAMS data as initial and boundary conditions (BC)?
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I am using WRF 4.1 in simulating weather parameters for Indian Region (9km). Initially I have been facing issues in configuring WPS, ARW post due to server architecture (IBM power series). Now i would like to get the wrfout* in .grib2 format and extension
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For grib format you can change compiler flag from O3 to O2 in configure.wrf also more information you can get in https://www2.mmm.ucar.edu/wrf/users/docs/user_guide_v4/contents.html
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I would like to find out how can I install and run WRF-Chem. I am already able to design and run WRF experiments on my own. Any documentation videos on WRF Chem other than those in Google?
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Aston thank you for you information.
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My question is back
I'm running the WRFV3.8,
I would like to have more vertical levels within the boundary layer.
I know the way of doing that. But I lack the ability to customize the vertical levels quickly. My main worry in the above is time-consuming.
How may I determine quickly that eta level 1 corresponds to 8m AGL without consuming time?
Then if I have to set, for example, 109 eta levels for my particular interest such as increasing the number of layers within the boundary layer, how to do that without consuming time?
Is there any way of generating them automatically?
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I think there is a file called "namelist" which you can edit it by changing the input characteristics such as vertical level number.
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I want to run WRF - ARW model for a small domain of 100X100 km at a grid size of 3X3 km or smaller for forecasting weather parameters, which will be used as an input in a crop simulation model to forecast crop yield.
I need to purchase the required hardware and software for it but I'm very confused of the requirements and specifications which are required for the purpose.
I seek help to answer the following questions:
(1) What is the minimum and optimum H/W specification required and available in the market (preferably in India).
(2) What Linux OS Version and other compilers that would required to be installed?
Thanks
Vinay Sehgal
Indian Agricultural Research Institute, New Delhi
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There is no need to use a very high specification to run WRF-ARW. Actually this depends on the resolution, region and time of forecasting. You need to install any suitable version of Linux such as Fedora, Obinto, etc. Then you should download, unpack, compile the source code that is available on the internet.
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I am interested in studying the effect of a mountain range on the intensity of low pressure. My question is: Is it possible to use WRF model to handle a hypothetical case that a certain mountain range does not exist and then get back to re-consider it again?
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Interested
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Dear All,
I am rarely facing this type of problem in one of my systems. I am using WRF-ARW model. The model is not producing the last time step. Say I am running the model for 10 days with 3 hours interval but at the last time step model stops and I am getting wrf_outfile also. Can anyone have any thought regarding this problem? I need suggestions from you.
Thank you in advance
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Okay, that's great!
Would you kindly tell what was the issue and how did you solve it?
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Hi everyone,
I am trying running WRF using ICON-EU as input data instead of GFS. So far I've been able to edit the WPS properly in order to add the soil levels that ICON uses.
However, when running ./real.exe I got the following error:
Using sfcprs to compute psfc
----- ERROR: The reference pressure is not monotonically decreasing
This tends to be caused by very high topography
(i,j) = 1 1 , topography = 0.0000000E+00 m
k = 1 , reference pressure = 100000.0 Pa
k = 2 , reference pressure = 100024.0 Pa
-------------- FATAL CALLED ---------------
FATAL CALLED FROM FILE: <stdin> LINE: 1236
In the dynamics namelist record, reduce etac from 9.9999998E-03
-------------------------------------------
This is usually an error that raises with high topography, but as you can se, topography is 0m in my case. I am almost certain that the error raises because ICON vertical levels are reversed: as you can see in the attached image (WRF at the left part and ICON at the right), ICON assigns the first level (lev=1) to the top one and the last level (lev=61) to the surface layer, while GFS and WRF level assignment starts at the surface and ends at the highest desired level. How can I reverse the levels in the ICON grib2 files so I can remove this error?
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Thanks for your answer! I finally managed to fix it just by updating the WPS version. WPSV4.1 rises the error but WPSV4.2 works fine.
And about the icosahedral grid, I am using the ICON-EU version with is restricted to Europe and uses regular lat-long grid that is accepted by WR. I didn't try the triangular grid yet, but it would be interesting add the capability of reading those grids in WRF
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Hi, I have been trying to run the WRF model for 24 hours over a month (September 2018). I am using three two way nested domains (9km, 3km and 1km) with 63 explicitly defined vertical levels over a part of peninsular India. My timestep is 30. I am getting cfl errors only on some days, while for others the model run is completed without any errors. I have used the same domains and other runtime options for the month of January, 2019 as well and had no issues there. What might be the issue here and how can I attempt to resolve it? Please help me out.
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I changed my time step to 18 and it worked. Thankyou!!
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I have the next error:
Timing for Writing wrfout_d01_2014-01-24_00:00:00 for domain 1: 0.71017 elapsed seconds
open_aux_u : error opening auxinput5_d01_2014-01-24_00:00:00 for reading. 100
d01 2014-01-24_00:00:00 Input data processed for aux input 5 for domain 1
d01 2014-01-24_00:00:00 Input data is acceptable to use: wrfbdy_d01
Ignoring all time series locations beyond # 20. Increase max_ts_locs in namelist.input
Timing for processing lateral boundary for domain 1: 0.09578 elapsed seconds
Tile Strategy is not specified. Assuming 1D-Y
WRF TILE 1 IS 1 IE 40 JS 1 JE 20
WRF NUMBER OF TILES = 1
How much should I make coarser the eta_levels? the area of study includes altitudes from 3000 to 240 m.a.s.l.
&time_control
run_days = 3,
run_hours = 66,
run_minutes = 0,
run_seconds = 0,
start_year = 2014, 2014, 2014,
start_month = 01, 01, 01,
start_day = 24, 24, 24,
start_hour = 00, 00, 00,
end_year = 2014, 2014, 2014,
end_month = 01, 01, 01,
end_day = 26, 26, 26,
end_hour = 18, 18, 18,
interval_seconds = 21600
input_from_file = .true.,.true.,.true.,
history_interval = 60, 60, 60,
frames_per_outfile = 1000, 1000, 1000,
restart = .false.,
restart_interval = 7200,
io_form_history = 2
io_form_restart = 2
io_form_input = 2
io_form_boundary = 2
debug_level = 0,
/
&domains
time_step = 15,
time_step_fract_num = 0,
time_step_fract_den = 1,
max_dom = 3,
e_we = 81, 100, 100,
e_sn = 81, 97, 97,
e_vert = 44, 44, 44,
eta_levels = 1.0000, 0.9940, 0.9900, 0.9860, 0.9820,
0.9780, 0.9740, 0.9700,
0.9680, 0.9640, 0.9600, 0.9520, 0.9420,
0.9320, 0.9210, 0.9060, 0.8930, 0.8760,
0.8650, 0.8560, 0.8450, 0.8341, 0.8225,
0.8103, 0.7948, 0.7746, 0.7494, 0.7133,
0.6742, 0.6323, 0.5876, 0.5406, 0.4915,
0.4409, 0.3895, 0.3379, 0.2871, 0.2378,
0.1907, 0.1465, 0.1056, 0.0682, 0.0332,
0.0000,
p_top_requested = 3000,
num_metgrid_levels = 26,
num_metgrid_soil_levels = 4,
dx = 9000, 3000, 1000,
dy = 9000, 3000, 1000,
grid_id = 1, 2, 3,
parent_id = 0, 1, 2,
i_parent_start = 1, 13, 60,
j_parent_start = 1, 22, 48,
parent_grid_ratio = 1, 3, 3,
parent_time_step_ratio = 1, 3, 3,
feedback = 1,
smooth_option = 0
use_adaptive_time_step = .true.,
max_ts_locs = 20,
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Try making "io_form_auxinput5" three zeros
The following link may help
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I have want to get wind map for a given region and compare with real data using WRF.
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You can use python or NCL. I will recommend the wrf-python. This module is developed by the NCAR. You can also use pyNGL and pyNIO.
In case you want to use wrf-python, the list of diagnostics is given in the following link:
The few lines code for wind and direction is following:
ncfile = netCDF4.Dataset("wrfout ilef") ws,pd = wrf.getvar(ncfile, "wspd_wdir")[0,:]
For wind vectors use the quiver in the matplotlib of python.
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Hi,
I am trying to set up WRF model and I would like to specify explicit eta levels. My study will primarily be focused on storms and the boundary layer, so ideally, I would like to have very high resolution upto 3 km altitude. I am using three domains of 9km, 3km and 1km resolutions, with two way nesting. I am unaware of any thumb rules we need to follow or factors we need to keep in mind while deciding the vertical levels. Can you please educate me about them and help me out?
Also, I was told that, in case we don't want to specify eta levels, the number of vertical levels needs to be
Height of model top/ (0.1*Resolution of innermost domain)
Can you please help me understand why this is the case?
My model top will be around 20km (50 hPa), so if I go by this rule, I will end up using 200 vertical levels. Please help me understand why it is necessary to have these many levels.
Thankyou.
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A related issue is the consistency between vertical & horizontal spacings. A paper was written by Mahrer in the 90s and another by by Fox-Rabinovich & Lindzen
All the best
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What is the best approach to simulate one year, for example, in WRF? I divided the simulations into 12 months, 52 weeks, or 5 days segments, as some papers have applied (but they did not justified this choice)? There is a best practice?
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Yes, when we previously used splitted runs, we added from 6 to 12 hrs spinup time. However as we tested it recently, spectral nudging performs well and with this option you one can run prolongated periods (we tested 6 months) without re-initialization.
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I am unable to find literature having acceptable rainfall performance criteria as is available for other parameters such as wind, temperature, etc. Is it correct to define a criteria based on the 90th or 95th or similar percentiles from the population of rmse, mean error values?
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Dear all,
we are trying to improve the representation of land use information in the regional climate model WRF for 1. aquaculture and 2. rice paddies in the Mekong River region (Vietnam). The major question is which existing land use class (from MODIFIED_IGBP_MODIS_NOAH classification) corresponds best to those?
If none of the predefined classes is suitable, we could add new classes to the LANDUSE.TBL, but we would need the parameters from experiments or from literature, i.e. albedo (ALBD %), soil moisture (SLMO × 100%), surface emissivity (SFEM %), surface roughness length (SFZ0 × 10 −2 m), thermal inertia (THERIN × 4.184 × 10 2 J/m 2 Ks 1/2 ), and surface heat capacity (SFHC × 10 6 J/m 3 K) for aquaculture and rice paddies, respectively.
Thank you very much for all kind of helpful suggestions.
Cheers, Patrick
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Please see the attached file if it is helpful:
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root@ubuntu-ideacentre-510S-07ICB:/home# sudo apt-get install libjasper-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package libjasper-dev
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As part of an automated script for installing WRF; Find below the script for installing jasper.
Note: ,there are two versions but one is commented. Comment and uncomment per your need.
cur_dir=`pwd`
inst_dir=$HOME/model
dep_dir=$inst_dir/wrfdep
inc_dir=$dep_dir/include
lib_dir=$dep_dir/lib
#### Downloading jasper tar files ####
##### Installing jasper-2.0.28 ####
echo "Compiling jasper ..."
tar zxvf jasper-2.0.28.tar.gz
cd jasper-version-2.0.28
mkdir BUILD &&
cd BUILD &&
cmake -DCMAKE_INSTALL_PREFIX=${dep_dir} \
-DCMAKE_BUILD_TYPE=Release \
-DCMAKE_SKIP_INSTALL_RPATH=YES \
-DJAS_ENABLE_DOC=NO \
-DCMAKE_INSTALL_DOCDIR=${dep_dir}/share/doc/jasper-2.0.28 \
.. &&
make
make install
##### Installing jasper-1.900.1 ####
tar zxvf jasper-1.900.1.tar.gz
cd jasper-1.900.1
./configure --prefix=${dep_dir} --enable-shared --disable-static 2>&1 | tee configure.log
make 2>&1 | tee make.log
make install 2>&1 | tee make_install.log
cd ${cur_dir}
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Hi,
I need column integrated total aerosol optical depth at a specific location. For this, I used WRF-ARW model and added AODTOT in iofields_filename as a text file. I extracted the variable through ARWpost after running WRF. I got AODTOT
as constant field throughout the forecast period. If I want to get time varying AODTOT, what are the things I need to change?. Please help me regarding this.
One more doubt is, what is the difference between AODTOT, AOD5502D, AOD5503D?. Out of three, Which variable I need to to use to get total integrated aerosol optical depth at a specific location using WRF-ARW?
Waiting for your reply,
Thanks & Regards,
Malleswararao M
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Hi
why AODTOT is zero in wrfchem output file?
what item i will be active for AOD value
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Hello!
I am trying to run WRF-CMAQ simulation to predict concentration of PM2.5 in Middle East domain. For WRF simulation, I need 6 hours raw data from a global climate model run based on A1B and A1Fi scenario but I can't find the data. I would appreciate it if you could help me to find proper data
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Though question. You can try NCAR site, which houses AR4 data for CCSM3.0:
However, I would recommend starting with the CMIP5 or CMIP6 data.
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Hi! I hope I worded the question properly.
I need to do multiple WRF runs for different experiments. Does anyone have an idea how to run multiple different instances of WRF from the same compilation?
My current set-up is I have a master copy of my successfully compiled WRF. which I copy multiple times depending on how many different simulations I want to run. My problem is this can get tedious, especially if I copy multiple folders many times, link my met_em*.nc files for each copied folder, and then edit the different namelist.input files.
I want to do a cleaner approach where I have a separate folder where my .nc files are located, another separate folder with my namelist.input, another folder for my outputs, while I only have one copy of WRF. This will also allow for automation of many instances of WRF.
Is this possible?
Thanks!
-BA
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You may try to run them with multiple run folders by duplicating the run folders and have corrected links to the wrf.exe and real.exe. In our case, we have modified WRF V3.7 to have ensemble simulation within our project.
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The error is
DYNAMICS OPTION: Eulerian Mass Coordinate
alloc_space_field: domain 1 , 273316856 bytes allocated
d01 2013-11-06_00:00:00 Yes, this special data is acceptable to use: OUTPUT FROM METGRID V4.2
d01 2013-11-06_00:00:00 Input data is acceptable to use: met_em.d01.2013-11-06_00:00:00.nc
metgrid input_wrf.F first_date_input = 2013-11-06_00:00:00
metgrid input_wrf.F first_date_nml = 2013-11-06_00:00:00
d01 2013-11-06_00:00:00 Timing for input 0 s.
*** Error in boundary condition specification
boundary conditions at xs 1
boundary conditions at xe 1
boundary conditions at ys 2
boundary conditions at ye 2
boundary conditions logicals are
periodic_x F
periodic_y F
symmetric_xs F
symmetric_xe F
symmetric_ys F
Am attaching rsl.error.0000 and namelist.input files. WPS was succesful.
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Ensure that the information in the namelist.wps is consistent with namelist.input. Also, try to check for strange values in the certain levels of the generated met_em files (e.g. met_em.d01.2013-11-06_00:00:00.nc)
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Dear all,
I am trying to run the WRF-Chem model v3.7.1 with chem_opt = 132 (CB05+MADE/VBS) and fire emissions from FINN; however the model hangs up after a few hours of simulation with no error messages. I also tried to run the model setting debug_level to different values but it does not reveal where the problem could be. 
Thank you in advance for any help/comment you could provide
Angel
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Hi Guo,
The only way I found to solve it was setting the chemdt to higher values. This kind of model run issues (hanging with no error messages) are often related to the time for chemistry. Try setting chemdt=0 which sets the chemistry time step to the same as the meteorology time step.
Good luck
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I am trying to calculate equivalent potential temperature (theta_e) from the WRF output. I tried using the formula mentioned in grads user, but the output is incorrect.
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For calculations, cdo
gives the best result rather than grads
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We are running WRF/Chem 4.5.1 with RADM2.
In the wrfchemi files, I am looking at the E_NH3, BIGALK and E_C3H6. In the wrf output file, there seems to be several variables related to VOCs, but I am looking only at 'ald', 'tol', and 'xyl'.
We are running two simulations, a control and a sensitivity scenario - in the latter, there were decreases in total pollutants emissions, including VOCs... However, I don't see much change in VOCs between the two simulations, neither in the emission files nor in the output files. If I look at other pollutants such as CO, NO2, etc. there is a change, but not for VOCs. I am not sure if I am missing something here.
Which variables in those files do you usually look into when you want to analyse the VOCs? I have limited chemistry knowledge so I wanted to hear from anyone who's got more experience.
Any comemnts or recommendations are appreciated!
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Hi Julio,
If you are changing both anthropogenic and biogenic VOC emissions and are not obtaining different concentration, the problem could be related to the boundary condition. Maybe expanding the domain may diminish this influence. Or using different database to provide this boundary concentrations.
If you are not changing the biogenic VOC emissions, and the final concentrations is similar, this mean that this emission type might the main source of VOC. Therefore, the chances in anthropogenic emission do not cause any effect.
You can summarize each VOC species emission (_NH3, BIGALK and E_C3H6 ) by sectors (anthropogenic, biogenic, fires, etc.) to see the most representative sector.
For curiosity, the O3 concentration also changed in the second scenario?
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I have an EDGAR emissions data-set. I would like to speciate the VOC emissions for CBMZ mechanism. Could anybody help? thanks
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I developed an R package to download and speciate EDGAR emissions data. The R package is eixport
chem_edgar speciates emissions data for several chemical mechanisms
Here a solution on StackOverflow
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I am doing wrf simulation to study is there any impact of LULC on extreme precipitation. So I need to use Bhuvan's latest LULC data.
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So, first you need to match/convert your Bhuvan's AWiFS LULC data classes into 24 classes of USGS classification. You can find the classes in the WRF user guide in the Chapter 3.
After the translation, you will have your data in the correct classification to insert in WRF. Now you need to convert the TIFF file (I am expecting you LULC data is a raster file) into binary format (BIL) required by WRF.
I usually use the convert_geotiff function from openWRF, which you ca find at https://github.com/openwfm/convert_geotiff
This tool will convert the tiff into binary and also will create the index file. This index file holds the information of your data, like resolution, description, extension, etc. (take a look in the other LULC in the geog folder).
After the conversion in binary format, move this files to a folder inside the geog data location (take care to not override the WRF default data)
The next step is to edit the GEOGRID.TBL file inside the WPS folder.
The GEOGRID.TBL holds the information of all land surface data to WPS/WRF, so you just need to edit the Land use section of the file, add one "name" to your data, set the interpolation method, and set the path to your data/folder.
This will helps WPS to find your data and how to proceed with it.
Next step is to edit your namelist.wps.
When you look at it, you will see the geog path is set to default.
for example, a wrf configuration of two domains, you will see something like this:
geog_data_res = 'default','default'
you just need to edit this line into
geog_data_res = 'name_you_set_in_TBL + default', ' name_you_set_in_TBL + default'
So, WPS will look first at the "name_you_set_in_TBL" data, and extract the LULC data to your domain. After extract your data, WPS will look at the default data to extract the other parameter to WRF
The chapter 3 of the user guide also helps you to set this variables, edit the GEOGRID.TBL, and namelis.wps.
Regards
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I want to run WRF-Real at higher resolution (100 m). For that I have to downscale WRF output data (1 Km).
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I need to count the number of days with, for example, a temperature the threshold of >5° degrees, in a WRF-output with daily mean temperature values. Anyone knows or have a script example of how to do that?
Thanks in advance.
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Nice!
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[shanti@master2 netcdf-4.1.3]$ make install
Making install in include
make[1]: Entering directory `/home/shanti/BUILD_WRF/LIBRARIES/netcdf-4.1.3/in clude'
make[2]: Entering directory `/home/shanti/BUILD_WRF/LIBRARIES/netcdf-4.1.3/in clude'
make[2]: Nothing to be done for `install-exec-am'.
test -z "/netcdf/include" || /usr/bin/mkdir -p "/netcdf/include"
/usr/bin/mkdir: cannot create directory ‘/netcdf’: Permission denied
make[2]: *** [install-includeHEADERS] Error 1
make[2]: Leaving directory `/home/shanti/BUILD_WRF/LIBRARIES/netcdf-4.1.3/inc lude'
make[1]: *** [install-am] Error 2
make[1]: Leaving directory `/home/shanti/BUILD_WRF/LIBRARIES/netcdf-4.1.3/inc lude'
make: *** [install-recursive] Error 1
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I think you are defining a prefix for netcdf installation which does not have the access for the user.
Also, if you are following this tutorial ( https://www2.mmm.ucar.edu/wrf/OnLineTutorial/compilation_tutorial.php ), in that case it is Important to note that, with ubuntu you should export path instead of setenv (that worked in my case). So, your this command:
setenv DIR /path_to_directory/Build_WRF/LIBRARIES
becomes
export DIR=/path_to_directory/Build_WRF/LIBRARIES
I hope if you follow this procedure, it will work as in my case it worked.
Let me know in case you face any problem.
Regards
Dhirendra
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I am trying to generate the be.dat file using the gen_be facility of WRF. I have 12 hour and 24 hour outputs from WRF at 00 UTC and 12 UTC for a month. When I try to run gen_be_wrapper.ksh on my system (which uses gfortran compiler) I get the following error for both the outer (8 km resolution) and inner(2 km resolution) domains.
---------------------------- FATAL ERROR -----------------------
Fatal error in file: gen_be_stage3.b LINE: 305
Could not open ps_u/2019040100.ps_u.e001
Can you please help me out here and tell me how this can be fixed?
Thankyou.
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Hi sir,
Thankyou for the response.
I checked the file paths and they were set properly.
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Hi all,
I am installing WRFV3-3.9.1 and WPS3.9.1 with intel (dmpar) compiler.
While compiling WPS, the following error is coming.
*************************************************************************************** Error : Not building geogrid. Check whether WRF is compiled in .../.../.../Build_WRF/WPS/...WRFV3 ***************************************************************************************...... *************************************************************************************** Error : Not building metgrid. Check whether WRF is compiled in .../.../.../Build_WRF/WPS/...WRFV3 *************************************************************************************** kindly, provide me the solution for the same.
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Hi Murk,
Can you please follow my WRF installation tutorial on YouTube.
Here you can understand step by step installation procedure.
Link-
Hope so it will help you.
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Dear all,
I intend to use SST data for my WRF runs, but data are in binary format and I need to convert them to GRIB2 format. I appreciate if somebody with same experience help me solve the issue.
Thanks,
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You can find SST data in NetCDF format then you can try using CDO to convert to GRIB.
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Hello Everyone I am Trying to run WRF model and incountering with an error while running WPS-metgrid.exe error is as below
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! Successful completion of ungrib. !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
dass@Tower:~/Build_WRF/WPS$ ./metgrid.exe
Processing domain 1 of 3
Processing 2019-11-03_00
FILE
ERROR: Error in ext_pkg_write_field
application called MPI_Abort(MPI_COMM_WORLD, 0) - process 0
I am using WRF V3.9 and Input data is GFS of FNL but error is same for both dataset
Please help me in this..
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This is because the GFS data was updated in June 2019 with a new format.
The solution: use version 4.0 of the WRF PreProcessing System (WPS) and use ungrib.exe from there. After this step, copy the files to the WPSv3.9 and run ./metgrid.exe.
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Hi, I am getting high dry bias for non local pbl schemes in WRF but temperature output is very good statistically compared to local schemes. What are the options for reducing this bias without changing the pbl scheme (maybe in dynamics options?). I would very much like your input as I have little experience with WRF yet.
Regards
Neeldip
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I have noticed this behavior using the YSU PBL scheme, which is a nonlocal PBL that causes an overmixed PBL, especially over areas with a well-mixed atmosphere. If you are finding dry bias over monitoring stations in urban areas, I recommend the use of the urban canopy model (sf_urban_physics), even the simpler one ( sf_urban_physics =1). Additionally, I would also activate the mosaic LU categories in NOAH LSM ( sf_surface_mosaic =1). These two options will incorporate sub-grid processes that help in heat flux, temperature, and humidity.
if you are interested, you can read this paper (DOI: 10.1175/WAF-D-14-00105.1) which makes a review of the PBL schemes in WRF.
Be careful with microphysics options, because I already tested some if them over Brazil and I found huge differences in modeled rain.
Regards
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I am using WRFV4 and I have successfully run ungrib, metgrid. But whenever I execute real.exe then its shows
"starting wrf task 0 of 1"
........
below I have attached namelist.input and scene print of the error.
Please have a look and provide me any fruitful solution.
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Hi again,
I finally found the solution for my problem in the official WRF user's forum in the post from the user "heddet":
With WPS V4.1, the default Sea-level pressure (PMSL) was changed to MSLET. However, this field is only available for GFS files beginning 10 May 2011 and for GDAS files beginning 14 January 2015. For older files, the Vtable has to be changed according to the description in Vtable.GFS.
In my case, real.exe crashed whenever I used either a newer version of WPS or old GFS files.
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I am trying to generate the track of a tropical cyclone using WRF. Initially I tried with basic WRF configuration with em_real compilation but didn't find any script to track down the cyclone path as em_real is not generating any vortex tracking data. So, I recompiled WRF with vortex follwoing & em_tropical_cyclone configuration. But the problem is, still my model isn't generating any ATCF data (or any vortex tracking data) & to be true I am now confused whether I am on the right track to generate those data. At present I am not focusing on forecast accuracy / track variations (will work on physics options later, currently focusing on generating the track data only). I am quite new in using WRF & it will be a great help if anyone can give me some insight on this issue on how to do it.
>. My namelist.wps & namelist.input files are attached below.
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Thanks again for your help. My problem is solved now. It was some file format issue which was causing problem while extracting variable data.
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I'd like to use WRF output data to force a land surface model (HRLDAS). HRLDAS requires grib2 forcing data and I have so far been unable to convert from netcdf to grib. There are a number of tools that allow the conversion the other way (grib to netcdf).
I have tried using:
cdo -f grb -copy WRFoutfile.nc test.grb
but get the following message:
"Warning (grbGetGridtype): Curvilinear grid is unsupported in GRIB format! Created wrong Grid Description Section!"
Many thanks!
Trevor
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Hi Trevor,
Why don't you regrid your WRF data to regular grids before trying to convert it into grib?
Please follow the CDO commands to grid netcdf file.
cdo -f nc -sellonlatbox,lon1,lon2,lat1,lat2 -random,r1440x720 template.nc
(1440x720 are global points so they determine the resolution of the intended template created in this command)
remapcon, remapbic, remapnn, etc methods are available to regrid your data
Hope this helps you!
Regards,
Kishore
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I have scatterometer data (Ocean wind vector) and i want to assimilate in WRF-ARW
I have wrfout file with t=96
Now I need to convert observation file which is netcdf file into LITTLE_R format f
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Hi Jayanti,
I found a link which might be helpful for you. In this, FORTRAN based application is used to convert NetCDF files to the Little-R format. Currently, it supports only the conversion of synoptical weather station data.
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Has any body run CB05 mechanism in WRF-Chem3.7 with CB05 emission. My simulation will hang there without any errors found in log files. I guess it is related to emiss_opt and emiss_inpt_opt options. And what I choose is: emiss_opt=15; emiss_inpt_opt=101; chem_opt=131. Actually, I am not quite clear about emiss_opt and emiss_inpt_opt options. Does any body know anything about it? Thanks!
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Hi Jianzheng,
Sorry to reply late.
I have not run WRF-Chem for years. You may check the file labeled with 'emiss' in chem directory.
My previous notes says:
emiss_opt and emiss_inpt_opt are combined. Emiss_opt is based on the speciation of your emission which will be read into the model (registry.chem). Emiss_inpt_opt tell the model how to deal with the emission input depending on the chemistry mechanism you choose.
Hope this help!
zhen
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WRF is a mesoscale model fully compressible and non-hydrostatic (optional: hydrostatic for calculation) and the order truncation error is a major source of uncertainty during the model calculation. So reducing this error we always approach higher-order accuracy methods. In WRF-ARW there are the methods: RK2 and RK3 available but not RK4 which has higher accuracy.
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In addition to my first answer, I would like to include some references. The splitting algorithm used for the time stepping in WRF is described in a very well-known paper by Wicker and Skamarock: Time-Splitting Methods for Elastic Models Using Forward Time Schemes (MWR vol. 130, page 2088) discussing all the options considered in the model including the order of approximation for the space derivatives.
Please consult the following quote (page 2089):
“Runge–Kutta time integration schemes of second or higher order can be constructed from basic Taylor series. Gear (1971, 34–35) shows that second-order RK schemes have one free parameter and third-order schemes have two free parameters. Hundsdorfer et al. (1995) discusses the relative merits of different RK schemes of the same formal order in time. To facilitate the incorporation of the splitting, the following third- order RK time integration algorithm using the flux differencing (2) is used as the basis for our time-split method“
>End quote
The reasons for selecting the third order scheme are explicitly discussed in Hundsdorfer et al. (1995).
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I am looking at a specific namelist.input tailored for urban areas.
Thanks.
p.s. WRF version 4.0
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Thanks a lot Ravindra!
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When running the WRF climate model, output for a single day is generally from 00Z to 00Z (6 or 7PM) depending on CST or CDT. The input data for the simulation for a single day is also from 00Z on the first day to 00Z on the next day.
I am using some of this output (daily max/minimum temperature, daily precipitation, and daily solar insolation) to drive a crop model. Before I run the crop model, I would like to see if it is possible to get daily output from my WRF model simulation to go from midnight (06Z) to midnight (06Z) instead. The reason for this is because it will give a more reasonable daily maximum/minimum temperature, precipitation, radiation values that can then be used as input into the crop model.
My question...how do I rearrange the time of my WRF simulation, so that my climate model output for a single day is valid from midnight to midnight? Any help would be greatly appreciated. Thanks!
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As far as I know, WRF is configured to work without thinking about offsets from 0Z. Otherwise it would complicate the use of the lookup tables and sub-daily parameters in the models (and parameterizations). My recommendation would be to handle the time conversion in your post-processing. The specifics would depend on which particular set of tools you use.
For example, if using the pandas library in python, you could use the DateOffset object to shift your time coordinate by the appropriate amount, then use groupby (by day) to get your daily statistics. On xarray, another popular tool in python, you can use the shift function to move move your data along your time coordinate, then use groupby to get your daily statistics.
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I need to plot wind shear from wrf-nmm outputs. inspite of defining "shr" field in rip-user-guide page, no file has been generated after "./ripdp-wrfnmm file.in all wrfoutput_file".
Would you please help me in this regard
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I found that
use:
feld=bsh5
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Also I have these questions:
2.What king of level spacing should we employ above the PBL for such studies?
3.Also what should be the model top height for such studies? Is it really necessary to go above the tropopause.
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Thanks
Ali Alwaeli
for the info.
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I use the GFS files as input in WRF, but I get an error when I try to change p_top_requested from 5000 to 1000 hPa. Kindly suggest.
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Jaya Thakur GFS model has updated several times. About 5 years ago,GFS data has 27 levels in vertical. Before June of 2019,GFS-v14 has 32 levels . And the recent update is in June of 2019. The core of GFS was replaced by new model--FV3-GFS. New data Parameter is here:https://www.nco.ncep.noaa.gov/pmb/products/gfs/gfs.t00z.pgrb2.0p50.f003.shtml
May be usfull to you.
NCEP is upgrading GFS from version 14 to 15.1 beginning with the 1200 UTC run on June 12, 2019. At that time, there will also be a chance with the real-time data product. This includes available pressure levels, file size, and the data directory structure. For the data directory change and the full description of the GFS upgrade, please see https://www.weather.gov/media/notification/scn19-40gfs_v15_1.pdf To handle the new GFS data, you must use the ungrib program from WPS V4.0 or later. You do not need to upgrade other programs to later versions. The output from the newer ungrib will work with metgrid and the WRF model from earlier versions. To do so, you can download WPS Version 4.0 or later, place it in appropriate directory, then type 'configure' and 'compile ungrib'. This will only build the program ungrib.exe. After you run metgrid, check the values for 'num_metgrid_levels' using ncdump. If you do not use the supplementary pressure level data, num_metgrid_levels will change (from 32) to 34 with the new data. You can also use the new namelist option pmin (unit Pa) for ungrib to limit the pressure level data ungrib processes. If you set pmin = 1000, then you will get 29 pressure levels.
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I am trying to use ERA-interim to drive the High-Resolution Land Data Assimilation System (HRLDAS) to run Noah-mp offline from a regional climate model (WRF).
I have so far been able to compile the model and download the ERA-interim data, but I am running into errors when I try to create the forcing files. It appears that ERA-interim GRIB files use a complex packing scheme and "contain additional flags in octet 14". Both of which throw flags in HRLDAS. Does anyone know if how to either acquire ERA-interim in a different format or convert between complex and simple packing schemes in GRIB1 files?
Many Thanks!
Trevor
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I forced HRLDAS with ERA5,NCL may help you!
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Forcing datasets (also called as analysis) of coarse resolution from global models already might have errors and the errors might further increase when downscaled for use in WRF due to interpolation of values. Since in nudging wed try to nudge our model outputs towards the analysis, doesn't that put the nudging technique at a disadvantage?
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In principle, robust nudging can PUSH the model toward a relatively smooth state and this may constrain its (model) ability to simulate extremes efficiently.
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I want to perform a WRF simulation, but I am unsure whether I should spinup as I am also doing nudging. So I have these questions basically.
1. Should I do model spinup if I am doing nudging along with it?
2. Several studies show different spinup time. What will be the optimal spinup period?
3. Whether spectral or analysis nudging is best for simulating precipitation in a very complex terrain?
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If the length of the simulations are only one month, the only spin-up that needs to be accounted for is the atmospheric one, which is typically only a few days. If I understand well, you are nesting two domains, the first one at 27km resolution (which is about the same as ERA5), and the second one at around 9km. In this situation, I would suggest to use 5 days spin-up in the beginning of each nested integration (so adding up both spin-up would lead to 10 days), and then begin the one-month simulation.
Maybe you could find the following paper of interest :
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Hi,
I downloaded grib2 data for Temp at 2m, U at 10m, v at 10m for the same period. Now how can I convert these three files as a single grib2 file?.
Thanks & Regards,
Malleswararao
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For grib files;
cat infile1.grb infile2.grb > outfile.grb
For netcdf files;
to merge along the time axis;
cdo merge infile1991.nc infile1992.nc outfile1991_1992.nc