Coupling the TKE-ACM2 Planetary Boundary Layer Scheme with the Building Effect Parameterization Model

Zhang, Wanliang; Ren, Chao; Ng, Edward Yan Yung; Wong, Michael Mau Fung; Fung, Jimmy Chi Hung

doi:https://doi.org/10.5194/gmd-18-7781-2025

Articles | Volume 18, issue 20

https://doi.org/10.5194/gmd-18-7781-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/gmd-18-7781-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 18, issue 20

Development and technical paper

|

27 Oct 2025

Development and technical paper |

| 27 Oct 2025

Coupling the TKE-ACM2 Planetary Boundary Layer Scheme with the Building Effect Parameterization Model

Wanliang Zhang, Chao Ren, Edward Yan Yung Ng, Michael Mau Fung Wong, and Jimmy Chi Hung Fung

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Final revised paper (published on 27 Oct 2025)
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Preprint (discussion started on 19 Dec 2024)
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Interactive discussion

Status: closed

RC1:
'Comment on gmd-2024-205', Anonymous Referee #1, 12 Jan 2025
Interactive reviewer comment on the manuscriptCoupling the TKE-ACM2 Planetary Boundary Layer Scheme with the Building Effect Parameterization Model
GMD-2024-205

By Zhang et al.

General considerations
In this contribution the authors present the coupling approach of an urban ‘building effect parameterization’ (i.e., the surface exchange parameterization) to a recently proposed (improved) boundary layer parameterization scheme for atmospheric RANS type models. The new coupled scheme is compared to a version with a bulk surface exchange treatment, and to the results from another PBL parameterization (one of the ‘standard schemes in the literature), once with the bulk surface exchange and once with the ‘building effect parameterization’. The approach is evaluated on two case study scenarios with an idealized surface characterization (regular cubes) and an LES (PALM-4U) as a reference. Then, a month-long simulation for the Pearl River Delta (China) with a number of mega-cities (including Hong-Kong) is performed. Data from three lidars (wind profiles), and 31 surface stations (urban and rural) are used for validation.
The study is well designed, and pretty well described (the ‘plan’ for the paper is good, and much of what needs to be known, can be found somewhere). I cannot say, however, that it is well written (I have added quite a number of ‘detailed comments’ – mostly related to language or formulations, etc.). A serious language/style update by a native speaker would certainly greatly improve the value of the paper.
Even if I have labelled one of the comments as ‘major’, I think its resolution is straight forward – so that I can recommend the paper to be published subject to minor modifications.

Major comments
Real case simulations & data: the presentation of the data is not complete. The lidars, when introduced should be characterized (urban, rural) and some basic information on vertical resolution and accuracy should be provided. Also, for the surface stations, information should be provided on the explicit meaning of the different LCZ classes (‘compact high rise, LCZ1, etc.), and how many are available for each type (how many urban, how many non-urban), what ‘G class’ (e.g., Fig. 17, 18, ..) means. Much of this can be found somewhere (I can, for example add the different numbers in each panel in Fig. 17) but the authors could support the reader in providing this information. Furthermore, Figs. 14-16 have 10 urban classes, plus ‘water cells’ plus ‘natural cells’, while Figs. 17-19 have 7 urban classes (the remaining three are probably not available) plus ‘G stations’ and ‘rural stations’: how do the latter translate to the water cells and natural cells? I suggest to add a sub-section in Section 2 with some of this information.

Minor comments
l.48 ‘…they work with few…’: maybe better ‘they have only been coupled to a few … (I think they would also work with all the other schemes – btu it has not been done)
l.60 ‘have shown that the TKE-ACM2….’
l.62 ‘at the urban station….’: this suggests that the reader knows which urban station is meant. Please rephrase.
l.72 ‘…from the high-resolution lidar’: same as before (this suggests that the lidar had been introduced before). Reformulate to ‘….from a high-resolution lidar’.
l.87        Energy conserving
l.84        ‘…K is the eddy viscosity….’. Do I have to assume that K is equal for all ‘zeta’ (l. 91). If not (what would be better supported by the literature) , K should also get an index zeta.
l.115      ’C_eps is an empirical constant and l_eps corresponds to….’
l.162      uniformly distributed in the vertical: this may be a good idea in a CBL but how about the near surface?
l.164      ‘…one corresponding to a moderately…’
Fig. 2, caption: the different types of lidars should be referenced (UTSS, HT, KP), and briefly explained (possibly in the text) what their strengths weaknesses are.
l.215      ‘…it is found that quasi-….’
l.215      ‘….when LES…’: how is the time for having reached quasi-equilibrium diagnosed?
l.223      usually called ‘turbulent fluxes’. However, it would be better to delete ‘outputted’ - these are just the ‘turbulent fluxes from PALM‘.
l.224      very often, what we can see in a figure has been plotted… (so, the verb ‘to plot’ is somewhat obsolete in this context). May be ‘….schemes are contrasted in …’.
Fig. 6, caption: please add for which case this RMSE is determined and what ‘the truth’ is (assumed to be). Fig. 6: I would find it ‘more convincing’ if the black dots would be displayed as a ‘dotted line’ (and not as a dot at each level) – then it would not appear as a black line in the lower parts of the panels……
231 ‘a smaller warm bias’ would possibly sound better

l..234     ‘becomes stable….’: this is indeed a feature of the CBL. Some authors have even defined a ‘neutral level’, i.e. the height where slightly unstable transits into slightly stable (formally, there might even be such a height in the LES)
l.241      ‘….within [the] UCL and near [the ]PBL height where the relatively constant w′θ′ in the middle UCL is not exhibited [reproduced?] in either BEP simulation.’. Here, I think this is a little ’underselling’ the BEP simulations. They at least to some degree reproduce a strong deviation in the profile at canopy height (the two others cannot reproduce this), the relax in the middle of the CBL (and yes, the vertical gradient is too small)…..
l. 249 ‘This has shown the wind shear at the roof level is underestimated…’: I am not sure what the authors want to say with this. Maybe this is just a matter of wording? – ‘thus it appears that the BEP parameterization results in an underestimation of wind shear at roof level, when compared to the LES’.
l. 250 ‘it is discovered…’: first of all I suggest to start a new paragraph. Second, momentum flux decreases (increases in magnitude…) with height. Third, ‘at some height’ (as it appears in the LES) seems to be some 2-4 canopy heights (in b) and d), respectively). Fourth, this cannot be called ‘discovered’ here – this was even one of the reasons for the development of the BEP scheme (i.e., that it had been discovered earlier, that momentum flux was not constant with height in urban canopies).
l.260      ‘similar behavior of the two schemes is found…’
l.275      I think the dashed line is blue in Fig. 5d
l.279      top of the RSL, rather
Fig 7       I suggest to repeat the definition of delta_U (i.e., BEP-Bulk) in the caption. Same in Fig. 8 for theta
l.300      beginning a new sentence: Figure 8…..
Fig. 9, caption: delete ‘plots the’ ; ‘at USTSS, HT and KP’: are these locations? I recall too have seen different symbols in Fig. 2 – and thought this to be different types of instruments. I suggest to add an ultra-short sub-section in Section 2, describing the instrument type, vertical resolution and some accuracy statements from the manufacturer.
l.306      …the rural lidar station HT (first, I learn now that the different symbols are different sites (see previous comment), but also I learn that at least one of the lidars is ‘rural’. Why not giving them an extension in the acronym?
l.306      at the LCZ 5 USTSS lidar location: wouldn't it be perfect to add this LCZ information to the section suggested in ‘comment to Fig. 9’?
l.308      ‘has been reduced’: the authors probably mean ‘is smaller in the BEP schemes….’
l.309      I don’t think there is a Fig. A51… Can the authors adjust?
l.312      starting at an altitude of 50 m agl?
Fig.10/11/12, captions: are these instantaneous values at the given times or 1-hour averages (in both, the observations and the simulation? Also, the caption may remind the reader that the panels start at 8 pm (why is this so?)
Fig. 13: RMSE and mean bias of WHAT? What is the data base? What are the ‘error bars’ referring to?
l.330      convective thermals
l.331      the smallest RMSE and the smallest negative bias….
l.332      Boulac+BEP, which increased the deviations with respect to the Boulac+bulk simulations.
l.334      I cannot locate Section 44.1. please adjust.
l.337      this is not predictability, rather ‘accuracy’
l.342      who is collaborating here with whom?
l.359      as small as…
l.359      ‘…is more likely to be found at around 06LT in TKE-ACM2….’: I don’t think this can be said like that. Do the authors want to say that ‘delta_U10 starts to be larger (in absolute terms) starting from about 06 LT’?
l.366      slightly altered?
l.369      the ‘supplementary Zhang (2024) is not a proper citation (in the supplementary material to Zhang….)
l.377      LC1…stations are …lower than the observed values’: this is, first of all, not a correct sentence (the simulated wind speed at these stations is smaller than…). Second this is a very important observation, which suggests that the authors should (maybe in the appendix) produce a table where the LCZ codes are described in words (having read the sentence, I, for example would wonder what LCZ2 is (it is also having much lower wind speeds than observed….). I suggest to add this finding explicitly to the conclusions (in the present form it states that LCZ1,4, 10 etc. are underestimating – but it is more relevant to state that high-rise and heavy industry types are underestimating.
l.383      ‘at the hill whose…..’: replace by ‘at a hill with a spatial scale of 50 m’.
l.388      ‘Coinciding with Fig. 15’? Maybe: ‘As can be seen in Fig. 15, T2….’?
l.391      ‘their predictability’: it is accuracy and not predictability
Figs17-19: what are ‘G’ stations?
l.400      again, it is not the predictability that is improved, but the prediction (i.e., its accuracy). Predictability is a property of the atmosphere (which is assessed using ensemble prediction approaches)
l.401      should read: ….BEP produces larger RH2 when ….
l.409      building-resolving
Figure 20, caption: Please add the information (in the caption) where the number of sites contributing to a LCZ type can be found.
l.419      BEP suggests that the buildings act..
l.421      …observations are used to…
l.425      …LIDAR station, compared to..
l.430      no predictability
Citation: https://doi.org/10.5194/gmd-2024-205-RC1
- AC1: 'Reply on RC1', Wanliang Zhang, 06 Mar 2025
  
  The comment was uploaded in the form of a supplement: https://gmd.copernicus.org/preprints/gmd-2024-205/gmd-2024-205-AC1-supplement.pdf
  
  Citation: https://doi.org/10.5194/gmd-2024-205-AC1
RC2:
'Comment on gmd-2024-205', Anonymous Referee #2, 07 Feb 2025

Zhang et al., 2025: Coupling the TKE-ACM2 Planetary Boundary Layer Scheme with the Building Effect Parameterization Model
The authors present in the manuscript a development and performance of coupling of TKE-ACM2 PBL scheme with BEP urban model in WRF mesoscale model. Although it describes important and interesting topic of improving of WRF model performance, and also the design of the study seems reasonably, the manuscript is not well written. Sometimes it is hardly readable, confused, some parts are too long but other information are missing. The manuscript have to be substantially improved (or re-submitted) before publishing in GMD.
Specific major comments:
1/ The text of the manuscript is not well transparent, some results parts are too long, model formulation could be also shorter or moved into the appendix. Some short sections (e.g. 2.4) could be removed and the number of figures reduced. Further, the manuscript is hardly readable due to often quick switching between ideas and also missing links to figures. It seems that it was not preciously revised by authors before submission.
2/ Language level is not sufficient, proofreading by English native speaker would be appropriate.
3/ Description of model setting is insufficient, BEP parametrization setting of urban canopy parameters in specific LCZ is missing. Author does not consider possible inaccuracy in the setting of such parameters with impact to model performances in specific LCZ.
4/ Description of LIDAR and station data is incomplete. Some special section about observation data is usual in papers, with information about measuring sites, variables, locations and other important characteristics in view of comparison with model data.
5/ Arrangement of Fig. 7, 8, 14, 15 and 16 shows rather impact of BEP urban scheme compared to Bulk, what is clear and well known fact, but not the impact of TKE-ACM2 PBL scheme compared to Boulac, which is the topic of the paper. Differences between simulations with/without TKE-ACM2 scheme should be rather displayed and also impact of TKE-ACM2 scheme more discussed.
6/ High number of mistakes, typos, wrong use of dashes and connectors (see below). I would recommend to authors to use latex with active references for all figures, sections and tables, to enable better orientation in the text (showing of references by click on) and to prevent mistakes in numbering of figures, sections and tables.
Other comments and technical corrections:
L 12 – comparison to Bulk method, similarly L 27, that’s not clear if Bulk is meant as some simple PBL scheme or simple urban scheme
L 19 – brace near brace doesn’t look well (L 32)
L 23 – 10-50
L 35 – mathematical formula as Fi is superfluous in introduction (similarly L 41)
L 44 – what is urban heat island circulation? UHI or circulation in urban areas.
L 48 – braces in braces doesn’t look well (L 63 similarly, L 154)
L 49 – word order … added recently by H…
L 51 – motivation better explained
L 160 – the horizontal resolution of WRF+BEP in idealized case is not clear
L 175 – WRF+BEP other setting is not described
Chap. 2.4 – why is it separated? Is is used in idealized case, or is it belonging rather to real case?
L 186 – you talk firstly about 10 LCZ and here about 17 classes
L 198 – the formulation “July 18 20 o’clock” is unclear, need reformulate. Similarly the following sentence.
L 204 – this sentence is without any notice about moving to WRF setting
L 205 – Bulk scheme is usually not considered as a canopy model (UCM), because there is no canopy
L 215--220 – acronyms are unclear, all sentences should be written better
Fig. 4 – dotted line is not well visible in plots
Fig. 5 – blue dotted and dashed lines are not in the legend
L 240–250 and further – links to figures are missing, the text is still switching between description of Fig. 4 and 5
L 256 – prorportion → proportion
L 274 – is blue dashed line non-local or local component? (sentence vs. Fig. 5 caption), there is also no red dashed line
L 275–276 – the sentence not clear
L 283 – fount → found
L 283–285 – the sentence is not consistent to claim in L 244. I think a different order of variables in Fig. 4 and 5 vs. Fig. 6 caused it. I would recommend to change the order of variables in Fig. 6
L 289 – what does mean “other natural landuse” – is it any crop, forest or pasture?
L 299 – besides urban grid-boxes, the BEP model is not used over natural and water grid-boxes in simulation, so it cannot produce any direct difference in U, only as an impact of neighbouring grid-boxes
L 302 – the sentence is not correct, there are other mechanisms except anthropogenic heat (e.g. shadowing of solar radiation by buildings), which cause lower temperature in BEP simulation in comparison to Bulk
Fig. 7 – there is no direct comparison of model and observation data
L 309 – there is no Fig. A51 in the manuscript
L 331 – rather “the lowest RMSE and the lowest negative MB”
L 335 – there is no Section 44.1
L 369 – in the supplementary Zhang (2024) → rather in the supplementary material of Zhang (2024) … or similarly
Fig. 17, 18 and 19 – it is not clear, how the stations are assigned to LCZ. Fig. 2 shows only 10 urban stations, but Fig. 17 etc. computes with 23 stations in urban areas.
L 382 – reported in (Ribeiro et al., 2021) – wrong braces
L 400 – “influence of BEP is relatively marginal on RH 2 at non-urban stations” this is quite trivial meaning when BEP is not operating in non-urban grid-boxes.
L 419 – “BEP indicates the buildings act as a sink of heat” – I think this is not a correct statement, there is no sink of energy, the reasons for lower temperature under BEP are different.

Citation: https://doi.org/10.5194/gmd-2024-205-RC2
- AC2: 'Reply on RC2', Wanliang Zhang, 06 Mar 2025
  
  The comment was uploaded in the form of a supplement: https://gmd.copernicus.org/preprints/gmd-2024-205/gmd-2024-205-AC2-supplement.pdf
  
  Citation: https://doi.org/10.5194/gmd-2024-205-AC2

Peer review completion

AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload

AR by Wanliang Zhang on behalf of the Authors (06 Mar 2025) Author's response Author's tracked changes Manuscript

ED: Referee Nomination & Report Request started (14 Mar 2025) by Jinkyu Hong

RR by Anonymous Referee #1 (23 Mar 2025)

Suggestions for revision or reasons for rejection

Reviewer comment on the manuscript
Coupling the TKE-ACM2 Planetary Boundary Layer Scheme with the Building Effect Parameterization Model
GMD-2024-205

By Zhang et al.

General considerations
The authors have made great efforts to react to the first reviews’ comments. This is particularly true with respect to language and clarity of the presentation. I nevertheless have a number of minor comments that I feel should be addressed before the paper can be recommended for publication.

Minor comments
(all lines refer to the ‘track changes’ manuscript [gmd-2024-205-ATC3.pdf])

l. 65 ‘….PBLs that are too shallow and moist in the evening…’
eq. (8) and (9). I overlooked this in the first version. There seems to be a mismatch in the use of variable name ‘z’ and ‘z_i’. You have introduced ‘z_i’ in eq (2) as the level heights in relation to the discrete parameterization for the fluxes. Here, a general profile is defined as a function of the height coordinate ‘z’. Therefore, all heights in these equations should read ‘z’, and not ‘z_i’. (this is particularly important because your case is a CBL, where usually the height of the inversion (CBL height) is denoted ‘z_i’.
l. 230 ‘…in Table B1’: here, it must become clear that this table is in Appendix B. → ‘….in Tab. B1 (Appendix B)’.
l. 253 ‘are provided in the supplementary material of Zhang (2024)’. If it is written like this, I assume that this is the supplementary material to https://doi.org/10.1029/2023JD040432, which is the paper on the turbulence parameterization TKE-ACM2. However, it seems that here, the supplementary material to the present paper is meant (i.e., the Zenodo publication of the data etc.). If so, the reference should read: ‚....is published on a data hub (Zhang et al 2024)’. Applies also to later occurrences of ‘supplementary material’…..
l. 256 same as l.230.
l.320 ….the boundary layer became sightly unstable….
l.322 ‘….was well simulated at roof level in BEP and PALM…’: but PALM is the reference (the truth) here – so, PALM only ‘well represents the expectations…’. Rephrase to the end that ‘BEP quite successfully reproduces the PALM reference’.
l.327 …in contrast to…
Fig. 6, caption: please replace ‘ground truth’ by ‘reference’.
l.333 ‘…leading to conduction’: I overlooked this is the first review, but heat conduction is likely not the reason for this behaviour. I would rather assume this to be a model artifact….(in the LES). This also concerns the following sentence… (I am not sure whether the PALM model includes conduction). Pease clarify.
l.349 ‘….to a minimum (maximum magnitude) value’. Please carefully review the use of maximum/minimum and decrease/increase in the entire paragraph (given the fact that the momentum fluxes are negative).
l.361 The two PBL schemes….
l.400 Figures C1 and C2 in Appendix C…..
Fig. 9, caption: ‚.... for the grid point of the observational sites (Fig. 2) USTSS (LCZ5), HAT (rural), and KP (LCZ1) from ...‘
l.434 In fact, L is most commonly referred to as ‘Obukhov length’ (Obukhov has published the length scale already some six years before the joint paper with Monin in 1954. Should be corrected in the entire manuscript.
Fig. 13, caption: again ‘reference’ instead of ‘ground truth’
l. 498 as l. 400
l.523 ‘remained positively skewed’. I don’t think we see the result of a skewed distribution here. They remain positively biased.
Fig. 20 why not the same colors as in Figs. 6 and 13?
l. 535 ….were considerably smaller…’
l.571 TKE-ACM2+Bulk

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RR by Anonymous Referee #3 (30 Apr 2025)

Suggestions for revision or reasons for rejection

“Coupling the TKE-ACM2 Planetary Boundary Layer Scheme with the Building Effect Parameterization Model” by Wanliang Zhang, Chao Ren, Edward Yan Yung Ng, Michael Mau Fung Wong, and Jimmy Chi Hung Fung

Recommendation: Minor revisions

General comments

This manuscript introduced an approach coupling the recently developed TKE-ACM2 PBL scheme with the multi-layer BEP UCM in the WRF model (hereafter, TKE-ACM2+BEP) and evaluated the performance of the TKE-ACM2+BEP approach in comparison to idealized LES for two convective PBL (CBL) cases as well as 1-month real-case observations. For both idealized and real cases, the simulations using the TKE-ACM2+BEP approach were compared with the TKE-ACM2+Bulk to investigate impacts of UCM (BEP vs. Bulk), with the Boulac+BEP to investigate impacts of PBL, as well as with Boulac+Bulk that differs in both PBL and UCM.
The coupling between the TKE-ACM2 PBL scheme and the BEP UCM scheme was made by 1) adding the forcing term computed by the BEP UCM to the rhs of TKE-ACM2 PBL tendency terms for prognostic variables including TKE, and 2) modifying the length scale in the TKE-ACM2 closure by considering the length scale comparable to the building height (l_build). The TKE-ACM2+BEP was verified in comparison to idealized LES for two CBL cases focusing on mean temperature and wind profiles and their corresponding vertical flux profiles. The real-case verifications in comparison to lidar wind profiles and near-surface meteorological parameters (U10, T2, RH2) were made for different land use categories, including 10 LCZ urban categories, water, and non-urban categories.
This manuscript is well written and organized providing details of the implementation that are essential to understand the coupling approach and verification results confirming that TKE-ACM2+BEP was properly implemented, showing great potential of TKE-ACM2+BEP to improve the WRF simulations for urban PBLs. I have several minor comments and suggestions.

Minor comments

Lines 114–115, “Ai and Bi”: Could you mention here that Ai and Bi are outputs from the BEP UCM? You mentioned it later at Line 125 for TKE, but I suggesting mentioning it to here as well.
Line 146, “anisotropic”: I think in general turbulence closure models in LES compute impacts of isotropic turbulence (assuming model resolution is in the inertial subrange), not anisotropic turbulence. Could you double check this for the PALM model?
Line 254, “observations”: I guess you mean “LES”.
Lines 293–294, “Boulac+BEP seemed to largely underestimate the momentum flux”: Due to the underestimation of the momentum flux, I expected Boulac+BEP would overestimate u/ug compared to TKE-ACM+BEP, like TKE-ACM2+Bulk and Boulac+Bulk underestimate the momentum flux and overestimate u/ug, for both 10WC and 24SC cases. However, Boulac+BEP rather underestimates winds compared to TKE-ACM+BEP. Could you explain why the momentum flux and the wind profiles aren’t consistent for Boulac+BEP? It shows momentum flux profiles closer to TKE-ACM2+Bulk and Boulac+Bulk, but u/ug profiles closer to TKE-ACM2+BEP.
Lines 414–415, “The four simulations generated T2 diurnal cycles with much lower amplitude than observations at water surfaces”: Could you confirm if the observations were also made over water surfaces (e.g., buoy) or they are over land surfaces surrounded by oceans? The observations show quite strong diurnal cycles of T2, which is not typical over water surfaces. If the observations were made over land surfaces while the simulations were at ocean grid points, this could be the reason why the T2 diurnal cycle amplitude is much lower in the simulations.

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ED: Publish subject to minor revisions (review by editor) (21 May 2025) by Jinkyu Hong

AR by Wanliang Zhang on behalf of the Authors (29 May 2025) Author's response Author's tracked changes Manuscript

ED: Publish subject to minor revisions (review by editor) (02 Sep 2025) by Jinkyu Hong

Please carefully check the comments below.

Reviewer #1 – Heat flux profiles (Line 333)
1) A more systematic explanation of the heat-flux profiles is needed in relation to Eq. (16) and the framework of Martilli et al. (2002). The newly added sentence appears to restate the preceding point (reduced heat flux near the roof level) without clarifying the underlying mechanism. Please make the causal chain explicit—i.e., how the terms in Eq. (16) lead to the observed profile features around the roof layer. If possible, please use the full and exact equations used in heat flux calculations of each parameterizations.
2) The manuscript suggests that heat conduction is the primary source of the warm bias in bulk models. However, it is not clear whether conduction is actually parameterized in the present configuration. Please clarify which processes are represented (e.g., slab heat storage, conductive transfer through roof/wall/ground layers) and how they enter Eq. (16). If conduction is not parameterized, the explanation should be revised accordingly.
3) This subsection is currently difficult to follow; a concise rewrite that connects equations, physical interpretation, and figures would greatly improve clarity.
4) Please also demonstrate—quantitatively—that the two bulk models produce different magnitudes of sensible heat flux (e.g., by referencing specific panels/figures and providing summary statistics).

Reviewer #2 – Momentum flux profiles (Line 333)
1) The authors’ response to the previous comment remains unclear and partially redundant. Please provide a streamlined, explicit explanation of the momentum-flux behavior and incorporate the key points into the main text at Line 333 (rather than only in the response letter).

Reviewer #2 – Momentum flux profiles (Lines 414–415)
1) Please add more detailed information about the observation stations (e.g., coordinates, elevation, LCZ/surface type, instrument height, averaging period) and include explicit cross-references to the relevant figures in the Supplementary Materials.

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AR by Wanliang Zhang on behalf of the Authors (10 Sep 2025) Author's response Author's tracked changes Manuscript

ED: Publish subject to technical corrections (23 Sep 2025) by Jinkyu Hong

AR by Wanliang Zhang on behalf of the Authors (23 Sep 2025) Author's response Manuscript

Short summary

This study focuses on improving the accuracy of numerical weather prediction (NWP) model particularly in urbanized areas. We coupled a recently validated boundary layer model with a building effect model within an NWP. Validation has been performed under idealized atmospheric conditions by benchmarking the coupled model with a fine-scale numerical model. Subsequently, the improvements and limitations are investigated aided by observations in real case simulations.