2019–20 Australian Bushfires and Anomalies in Carbon Monoxide Surface and Column Measurements

Round 1

Reviewer 1 Report

Reviewer comments attached in docx file.

Comments for author File: Comments.pdf

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments/ suggestions that can improve the clarity of the text and the correctness of some terms.

L30 replace “with modelling indicating” -by- “with modelling results indicating”

L39, L41 avoid repetition of “means” – Suggestion:… in the Southern Hemisphere,  make fires the major contributor…

L45: ..” and large atmospheric background”, Add a value for the background CO2, e.g. from the GAW station Cape Grim.; more appropriate is the word “high”. Also here - re-phrase to avoid the word “mean”

L51: “after major fires at heightened concentrations” – “after significant fires at increased (or elevated) concentrations

L57: “removal via its primary sink, OH.” – “ and OH (hydroxyl radical) oxidation removal”

L68: “global network of Fourier transform spectrometers” - global network of ground-based Fourier transform spectrometers

L102-103 spell out MOPITT and IASI

L132-133 replace enhancement by a more appropriate word, e.g. increase; also modify “in situ CO?” as “in situ CO concentrations?

L145-147. Delete ”meteorology” after inversion layer. It seems that the sea breeze interacts with other local circulations (due to the escarpment), so the formation of inversion layers is probably a result of the complex local atmospheric circulations.

 L162. “FTIR instrument measures from 1750”-  FTIR instrument measures wavenumbers from 1750

L186. at the end of the section on TCCON - Add something about measurement precision or accuracy for CO.

L261. “prolonged enhancement” -  long-lasting significant increase

L264 “ prolonged” – Can you add the number of days/weeks with increase CO in 2019-2020 bushfire period?

Fig. 4 –Legend – make symbols and letters bigger

L268. enhancement – increase ( the most popular word for concentrations changing from lower to higher values is increase)

L272. "The seasonal cycle of CO" – to mention that is based on multi-year data, eg. “Seasonal cycle of multi-annual monthly mean CO values”

L274 “spring maximum (August-October)” : Please verify as in Fig. 5 it seems is in (Sept-Nov). Or you mean increase in CO ? – Please, revise

L276-277 and L286:  primary biomass burning season, Do you mean -  primary sources from biomass burning during… months ? I suggest for clarity to add the months in these sentence

L287-293. This paragraph is more suitable for the discussion in 4.1  moving also Fig.6 under 4.1.

Fig.6 (i) Legend – make symbols and letters bigger; (ii)  Figure caption – add what is the top, and what bottom panel, explain abbreviation MAD also in Fig. Caption

L296 - Section 4.1. “The background surface CO is estimated using on-site data during the bush-fire period”. Could you provide the range of values of the so estimated surface background CO concentrations? Have you looked at GAW station Cape Grim data for this period? As a remote site it could provide background values for the region. Please add a small comment on this.

L323 “comparison of 2019-20 bush fires” – comparison of XCO metrics for 2019-2020 bush fires

L324 explain abbreviation FTS

L324-326: This sentence :” In addition, the long-range transport from South American fires in October 2010 also results in marked CO anomaly in the column data record (mean XCO anomaly = 27.25 ppb over 6 days)” - refers to Fig.6 (and not to Table1), so it should be moved backward in the text.

L331.  The word “enhancement” is crucial for understanding the discussion in this section. In the previous sections it was more as a synonym to “increase” in CO or XCO values. If here it is used for anomalies (estimated as in 4.1.) the word would be anomalies.

This is strongly related to the criteria (L337) – see further

L333 – “The aim .”.should be at the end of the Introduction section. Here one can start as: We analyse here if…

L337 – “criteria” – You mean the metrics in Table 1 or the anomalies?  It is better to define again clearly the criteria used to mark the periods in Fig.7

L343, L354,L359,L362: The numbers for % need additional clarification: L343 Only 20% of the time series there is coincident of surface and column data. Then, in 71% out of the above – there is column+surface “enhancement” .. Could you provide the length of the periods (hours, 10-days mean or else) corresponding to the above % ?

Fig.7: On both panels there are intervals with increase in CO ( or XCO) , but they are not marked with any type of colour vertical bars - e.g. for the column ( bottom panel) there is an increase around  Dec 8.,  Dec, 20, Jan.15. For the FTIR (surface) data – Dec18-19. This implies to explain better the criteria used for selecting the 3 categories of periods, discussed later on. From the following sections one can also conclude that the periods for the different colour bars are more (as number) than the ones indicated in Fig.7. Please check again position of colour bars in Fig.7 adding additional information in the text ( if necessary).

L369-370. the column CO values (~80 ppb - 160 ppb) – add  “hourly”, and provide values for the surface CO

L371 relatively constant background – Could you provide background value for this day

L393 “double planetary boundary layer”  You mean perhaps stacked layers with different characteristics, PBL can not be “double”. Please correct with “formation of stacked layers”, or other phrase

L407 “Combined, these point to” – suggestion: "This highlights the role…."

L422 “in both the surface and column” - in both the surface and column values.

L446 many satellites such as MOPITT – Please correct -  MOPITT (Measurements of Pollution In The Troposphere)) is the instrument on-board of NASA Terra satellite; and provide REF to its data. Also useful is to add the horizontal resolution and the overpass time for the region – time of day and frequency

L491 differences in the column and surface - differences in atmospheric dynamics and respective in CO concentrations both at the surface and in the column

Author Response

Please see the attachment.

Author Response File: Author Response.pdf