Methodology for Lidar Monitoring of Biomass Burning Smoke in Connection with the Land Cover

Round 1

Reviewer 1 Report

Title: Methodology for lidar monitoring of biomass burning smoke in connection with the land cover

Authors: Mariana Adam, et al

The manuscript reports the study of 11 aerosol pollution events of smoke by using Raman lidar measurements together with the Hysplit dispersion model in order to understand the originations.

The results from these studies are very useful for the researchers who is interested in the biomass burning aerosol monitoring and in its applications.

The whole paper was well organized and written in English. The studies and the conclusion are reasonable. However, the quanlity of the figures should be improved.

The referee finds that the manuscript could be accepted for publication after the quanlity check.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript describes a method to attribute ground-based lidar measurements of smoke plumes to the underlying land cover type that is burning. The primary measurements are from a multiwavelength Raman lidar operating in southern Romania. Smoke plumes are identified manually within the Raman lidar data and then an ensemble of Hysplit backward trajectories is used to determine the upstream fire source as reported by the MODIS FIRMS inventory. The method of Amiridis et al., 2010 is used to estimate plume injection height, and if the plume height is above the upstream airmass height predicted by Hysplit then the fire is assumed to be the source. MODIS land cover products are used to attribute a land cover type. 

 

The manuscript is exceptionally well prepared, with ample background material to place the current work in context with other efforts on lidar measurements of biomass burning. The methods and materials are clearly explained, and references are given to support algorithms used that are published elsewhere. The method to attribute lidar observations to source fires and land type is scientifically sound. One aspect that could help improve the manuscripts' arguments is to provide evidence that the layers being considered are truly dominated by smoke rather than some other aerosol type. The source direction of the plumes being considered are landward, so marine aerosol is unlikely. But is dust a possibility? The method demonstrates conclusively that smoke is upwind of the lidar site at the correct altitude, and the plume optical properties reported in Figure 9 are consistent with smoke, but it does not explicitly discount other aerosol types. The lidar ratios reported in Table 6 are in the range expected for dust at 532 nm. It is recommended that some comments be added to bolster the assertion that the layers considered are primarily smoke and not other aerosol types.

 

Beyond the previous comment which can be handled with a minor revision, the paper is in great shape for publication. It is well within the scope of Remote Sensing. The method is novel and would provide an excellent contribution to the community working to understand the impact of biomass burning on the atmosphere based on the fuel being burned. 

 

Specific Comments

 

Lines 42 and 528: The word “extend” should be replaced with “extent”. 

 

Lines 154, 343, 627: “insitu” should be “in situ”

 

Lines 178-180: Are these thresholds meant to isolate smoke layers from other aerosol types or does this statement refer to the range of valid measurements expected? Please clarify. Why is depolarization not considered as part of the IPs? Lines 166-167 suggest it is calculated and depolarization could be used to demonstrate that the layers being considered are smoke and not dust. 

 

Table 2: The formatting of the text could be improved. Currently, the space between each line is the same so when a land cover type requires two lines, like grasses or cereal, it looks like two distinct types rather than one. Perhaps this will be improved when the article is typeset. 

 

Line 375: Because the measurement site is southwest of Bucharest and the air mass came from the northeast, how certain is it that this lower layer is dominated by smoke from afar as opposed to anthropogenic pollution generated within Bucharest?

 

Line 384: Figure 2 and Table 3 suggests that the lower layer has a mean altitude of 1500 m, but Figure S7 shows the mean altitude at 2790 m. Is Figure S7 the correct reference here? Also this sentence suggests nine fires contributing to the lower layer, but Figure S7(a) only shows two fire locations. Are there more than one fire at these locations? Perhaps Figure 3 is the correct reference?

 

Figure 2: Why are the extinction error bars so much larger at 532 nm compared to 355 nm? Perhaps a comment could be added in the methods and materials section (at the authors discretion; this might not be necessary).

 

Table 3: It would be helpful to indicate if this is the mean or median layer altitude in the table or its caption.

 

Figure 3: The units for FRP should either be added to the middle panel title or to the legend. This would apply to those figures in the supplement as well.

 

Line 441: The word “percent” is not needed because % is already used.

 

Figure 6: It would be helpful to mark the lidar measurement site on this map.

 

Line 547: “Easter Ukraine” should be corrected with “Eastern Ukraine”.

 

Table 6: Units should be added in the first column for the layer bottom and layer top. Also, it would be helpful to add a row of the layer mean altitude since the discussion in the text and in the supplemental figures use this to refer to specific layers (just a suggestion).

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

1. the authors study the smoke layers using lidar and other tools linking to land cover，it is useful and the paper is well-written.

2. The paper cover 11 smoke layers in 2014, 2016, and 2017, why there is no observation in 2015?

3. in the paper, one  case study (as for 25 July 2016)  was to be illustrated, which is representative for five out of 11 cases, it is better to add the other case to represent for the other 6 out of 11 cases.

4. as for Figure 8. Intensive parameters versus smoke travel time. there is  good correlation.

Author Response

Please see the attachment

Author Response File: Author Response.pdf