Performance of KMA-ADAM3 in Identifying Asian Dust Days over Northern China

Round 1

Reviewer 1 Report

This short paper is an interesting and useful addition to the literature on dust detection modelling. It is worthy of publication with just a few small changes. Below are specific issues:

L29-31 the authors are correct in mentioning many adverse effects of dust, including those on human health, agricultural land, infrastructure and transport. However, all the references they cite refer to human health effects only. See for example Middleton (2017) for a wider array of examples and references.

L31-33 the authors make the interesting point about arid region expansion in eastern Mongolia and Manchuria leading to higher dust event frequency. This is OK by me, but their paper is about Chinese sources and so they must also make reference to the many papers that have noted a decrease in Chinese dust event frequency in recent years (e.g. Fan et al. 2014, Lee and Sohn 2011, Zhu et al. 2008) which may be related to warmer temperatures/greater rainfall causing arid region contraction (e.g. Piao et al. 2007, Sternberg et al. 2015), and/or to government-sponsored land restoration and afforestation schemes (e.g. Tan et al 2015). However, the impact of afforestation schemes is a matter for debate (e.g. Wang et al. 2010, Middleton 2018). It would be interesting also to hear the authors' view on how the various changes in dust event frequency in source areas affects dust transported to Korea which Kim (2008) - their ref [3] - notes has been increasing over 40 years.

L58 ‘the first half of 2017’: please state which months (January – June?) and reiterate the point made on L29 that this period includes the spring months, which are usually the dustiest in this part of the world.

Figure 2 what exactly do the dots represent? (I thought they would be MEP observatories, but this cannot be because there are not 355 dots).

L156 what is CSI?

L207 Conclusions: I would like to see the authors suggest some possible explanations for the poor performance of ADAM3 in estimating dust days in northwestern China. This is especially interesting given ADAM3’s improved performance in identifying dust days over sandy soils which are prevalent in northwestern China.

References

Fan B, Guo L, Li N, Chen J, Lin H, Zhang X, Shen M, Rao Y, Wang C, Ma L (2014) Earlier vegetation green-up has reduced spring dust storms. Scientific reports 4:6749

Lee EH, Sohn BJ (2011) Recent increasing trend in dust frequency over Mongolia and Inner Mongolia regions and its association with climate and surface condition change. Atmos Environ 45:4611–4616

Middleton, N., 2017. Desert dust hazards: A global review. Aeolian research, 24, pp.53-63.

Middleton, N., 2018. Rangeland management and climate hazards in drylands: dust storms, desertification and the overgrazing debate. Natural Hazards, 92(1), pp.57-70.

Piao, S.; Fang, J.; Liu, H.; Zhu, B. NDVI-indicated decline in desertification in China in the past two decades. Geophys. Res. Lett. 2005, 32.

Sternberg, T.; Ruef, H.; Middleton, N. Contraction of the Gobi Desert, 2000–2012. Remote Sens. 2015, 7,1346–1358.

Tan, M.; Li, X. Does the Green Great Wall effectively decrease dust storm intensity in China? A study based on NOAA NDVI and weather station data. Land Use Policy 2015, 43, 42–47.

Wang, X.M.; Zhang, C.X.; Hasi, E.; Dong, Z.B. Has the Three Norths Forest Shelterbelt Program solved the desertification and dust storm problems in arid and semiarid China? J. Arid Environ. 2010, 74, 13–22.

Zhu C, Wang B, QianW(2008) Why do dust storms decrease in northern China concurrently with the recent global warming? Geophys Res Lett 35(18):L18702

Author Response

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Reviewer 2 Report

Quality forecasting of dust days is an important task, especially from the point of view of the protection of human health but also the protection of property. Such models are very desirable as long as they seem to work correctly. The study points to the ability of the ADAM3 model to predict dust days, where it has improved or where it has shortcomings. The article is factual and high quality and I recommend accepting it.

Author Response

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Reviewer 3 Report

The authors present a comparison between two versions of the Asian Dust Aerosol Model (ADAM) models (3 vs. 2) in identifying dust events in China”, during the first half of 2017.

It seems that ADAM is essentially a dust emission model. Among other issues, the authors need to clarify this point.

I believe this manuscript needs to be improved, and after a new review, take the decision about its potential publication in Atmosphere.

These are my specific questions or recommendations:

In the Abstract: I suggest to indicate the improvements firstly when using ADAM3, and after its limitations. The authors should include values of at least one metric to show the performance of both ADAM3 and ADAM2.

Grammar and writing need to be checked by a native speaker.

Improve the resolution of all the figures.

Line   29: Change “Asia, where Asian dust events are ..” to “Asia, where dust events are ..”

What are the anthropogenic emissions included in ADAMS?. How were these emissions estimated?

What are the surface vegetation properties ingested in real-time by the model?. It is mentioned in the Abstract.

What is the dust emissions reduction factor?

Include a table of the main components of the ADAM2 and ADAM3 models.

Line   54: fine PMs?

What kind of model is ADAM?. It seems it is a dust emission model. If ADAM3 is an emission model: How does it assimilate the surface-observed PM and satellite-observed AODs?. It needs to be clarified in the manuscript. If so, the authors indeed analyzed the performance of a system composed of a meteorological component (UM) and emission component (ADAM) and a dispersion model?. If so, the title should be updated.

The dust emission model must be appropriately described in the manuscript, highlighting the variables involved, and how the model considers the influence of vegetation and rainfall.

It is necessary a figure about the region of study, highlighting the main soil types and the areas mentioned in the manuscript (e.g. Mongolia, Manchuria) and the surface stations which provide the PM concentrations.

How the parameters involved in the emission model-as the threshold friction velocity or the roughness height-were obtained?

The authors indicate that the difficulty for determining the presence of dust event in the Tibetan plateau, they have excluded the Tibet type from the analysis in this study.  It seems like a comfortable solution. It requires a proper explanation. The authors should indicate how this exclusion can affect the research and highlight this potential limitation in the Discussion section.

As natural emissions were included, it should be about VOCs?. If so, it seems the modeling approach not only considers dispersion?. It needs to be clarified.

Other features about the modeling approach should be described as domains of study, spatial resolution, and a summary of the main parameters or schemes.

It is not necessary to repeat that the period of study is the first half of 2017.

Why have the authors assumed two values (one for measurements and the other for modeling) for identifying dust events and not a unique one?.

What is the temporal resolution of the concentrations of fig. 1 (b). Are they hourly concentrations?

Line 125: “We evaluated four measures of accuracy for binary forecasts”. Does it seem the authors used "measures" as "metrics"?. Change in all the manuscript “measures” by “metrics”. What do you mean by binary forecast?

Include a table to summarize the H, M, FA, and CR relationships.

Indicate the values for the metrics HR, TS, POD, and FAR. E.g., HR=100% in case of a perfect fit between dust days identified by records and by the model.

Line 137: The Asian dust day threshold value obtained in Section 2  …Change to “The Asian dust day threshold value presented in Section 2  …”

Improve the legibility of figures 2 and 3. They must clearly indicate the region of the study, and the countries and deserts mentioned in the text. Indicate the meaning of the scale. Coordinates are too small.

Maybe a new figure is required to indicate the regions used for the modeling performance?. Or put the name of these regions in the legend of Fig 3.

Figure 3 (b). It shows the critical success index (CSI)!. This parameter was not previously described.  Also, it was mentioned in line 156!. Something seems wrong with this parameter.

Numbers indicated in lines in lines 153 to 159, need to be revised. Some do not correspond to reported in Table 1.

Add in Table 1, the total number of modeled days n.

What are the potential reasons for the overestimation of the loess area?

The subtitle “Analysis and Discussion” section should be changed to “Results and Discussion”.

It is not easy to understand the phrase “For Gobi-type soil, TS (37.4%) and POD (57.2%) were improved by 29% and 54%, respectively, from 29.0% and 37.2% in the ADAM2 simulations”. It can be written as “For the Gobi-type soil, TS and POD improved from 29.0% and 37.2%, to 37.4% and 57.2% respectively”. Similar changes should be done in similar sentences.

In Fig. 4 the one to one line should be included, and the corresponding equations and R2 of the linear relationships. In this figure, what does each point represent?

The Discussion sections fair and needs to be improved.

The Conclusions section is almost a repetition of the previous section. Conclusions also need to be improved.

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

I reviewed the updated version of the manuscript entitled: “Performance of KMA-ADAM3 in identifying Asian dust days over northern China”.

I also read your answer submitted about the observations, questions, and suggestions to the first version of the manuscript.

You have incorporated or addressed the points of my review correctly. You have made a good job. 

I consider your article can be published in Atmosphere.

Best regards.