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    Hello! I just have a simple question. When using Noah LSM, I see SHDFAC (vegetation fraction) in the VEGPARM.TBL. In the same time, I see another variable related to vegetation fraction, which is named VEGFRA from static data. Which is used in the model, SHDFAC from table or VEGFRA from static...
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    Latent Heat Flux Is Zero in Urban Land

    Hi Ming, Thank you for confirming this. I will dig into this to see if I can modify the code a bit to output a representative EM value for the urban portion. Thank you again!
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    Latent Heat Flux Is Zero in Urban Land

    Hi Ming, I'm sorry to bother you again. Please let me first thank you for taking time to help me out! After you last explanation, I continued to explore more model results and the codes. I just want to report something I found and would like you to confirm if my understanding is correct. You...
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    The surface roughness issue in UCM

    Hi, I think this issue (or maybe not) has been discussed a bit. But I'd like to re-discribe it based on my situation. I used WRFv4.3.3 to model the Urban Heat Island in Logan, Utah. The boundary conditions were provided by the HRRR dataset with 3-km resolution. I used MJY PBL scheme. I did two...
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    Why roughness(ZNT) of Urban is lower than Croplands in UCM?

    Hello, I encountered the same issue using WRF v4.3 with BEP model. Urban girds initially had ZNT of 0.8 (default in LANDUSE.TBL), then had the ZNT drop to 0.14, which is an unreasonable value for built-up area. Have you come to a solution? Many thanks
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    Does wrf use 2-meter temperature for initialization?

    Hello! I have a simple question. Does WRF use 2-meter temperature/relative humidity from the reanalysis data for initialization? I used ECMWF data (0.08 degree) for initial and boundary conditions. The archive has atmospheric isobaric analysis and surface analysis data. For the surface data, I...
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    Latent Heat Flux Is Zero in Urban Land

    Hello Ming, I want to thank you for exploring this. I really appreciate your explanation. I took a look at module_sf_noahdrv.F and found the emissivity is set to 0.98 for an urban grid. Is that just for the urban vegetation or for the whole grid? Say there's a urban grid of LCZ 6 (65% urban...
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    What is the most reliable way to inject WUDAPT data?

    Hi all, I'm trying to modify the land use in my domain with urban information from WUDAPT data. My study area is out of the US so I guess I have to use WUDAPT instead of using the binary NUDAPT data. My general questions is, what might be the most reliable way to inject WUDAPT data so the...
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    Latent Heat Flux Is Zero in Urban Land

    Thank you for your work and take you time. I'm moving to the canopy model now to see if I can bypass the strange results since urban class will have vegetation fractions.
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    Latent Heat Flux Is Zero in Urban Land

    Hi Ming, I did check that. They did change with time. Please see the picture attached. I picked an urban grid, a forestry grid, and a grassy grid, and plotted their soil moisture at the first layer of GFS data (0-10 cm) with time. A big jump occurred on around July 12th, which I guess is due to...
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    Latent Heat Flux Is Zero in Urban Land

    Hi all, I need some help to understand what I'm seeing in my modeling results. I'm running a 2-way nested case with double-domain in Guangzhou, China, a city with humid summer. I use WRF and WPS 3.9, MODIS 21-category land use data, and BNU global soil type data, all can be accessed from the...
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    Initial Conditions

    Hi, Sorry I have a quick question. I have understood that the initial and boundary conditions from the reanalysis data will show the differences in background climate. The impacts will be not only on the soil moisture but also on other atmospheric variables. However, I found a variable named...
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    Initial Conditions

    This is a perfect answer to me. Thank you very much.
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    Initial Conditions

    Hello! I'm not sure I understand the term 'Initial conditions' in WRF modeling and would like some help. If I simulate in nested domains, I need observational (model) data such as GFS to set up the initial and the boundary conditions. Such data are time-dependent so I understand that the model...
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    Ground Heat Flux too large

    Hi I'm a WRF starter and would like to test unified Noah LSM with the landscape mosaic feature. My AOI is the New Haven County, Connecticut, US, which is an urbanized area. I simulated for a couple of days (July 05-08, 2020) and checked the time series of Sensible Heat, Latent Heat and the...