The quality of the revised manuscript remains below the standard expected for publication in the ESSD journal. Numerous inconsistencies, spelling and grammatical errors, scientific inaccuracies, unclear references, and unrelated citations persist throughout the manuscript. Specifically, the 'Introduction' and 'Materials and Methods' sections suffer from poor presentation, characterized by lengthy and convoluted sentences, as well as disjointed transitions.
During the previous round of revision, it appears that the authors addressed only the errors pointed out by the reviewers without proactively seeking to identify and rectify similar issues elsewhere in the manuscript.
While the 'Methods', 'Results', and 'Discussion' sections present scientific findings, they fail to significantly advance the field beyond the utilization of a different satellite active fire product. Many of the methodologies employed in this study rely on outdated knowledge and overlook recent developments.
Based on these observations, I do not recommend publication of the manuscript in its current form. A substantial overhaul of both the textual presentation and scientific discussion is imperative for future consideration of this manuscript for publication.
Below, I outline some of the issues observed in the 'Introduction' and 'Materials and Methods'. Please note that this list is not exhaustive, and it is essential for the authors to enhance the overall clarity and coherence of the manuscript.
P1 L16-17: “Global high–resolution satellites can detect active fires, enabling a more accurate estimation of these emissions.”
Regarding the term 'more accurate', it's important to specify what the comparison is being made against. Without a clear comparison, the statement lacks clarity.
The phrase 'these emissions' is ambiguous as it doesn't specify which emissions are being referred to. It would be helpful to clarify that these emissions pertain to those from Open Biomass Burning (OBB) to enhance the reader's understanding.
P1 L19: “satellite and observational biomass data”
While "satellite biomass data" is a type of observational data, the phrase "satellite and observational" is redundant. Consider using "satellite-derived biomass data" or "observational biomass data" to avoid redundancy.
P1 L19: “vegetation index–derived spatiotemporal variable combustion efficiencies”
Consider revising "spatiotemporal" to "spatiotemporally" for grammatical correctness.
P1 L20: “The average annual OBB emissions for 2020–2022 were…”
Specify that these values are estimates derived from the study rather than presented as absolute facts. For example, consider revising to "The average annual estimated OBB emissions for 2020–2022 were..."
P1 L23-27:
The average annual OBB emissions for different regions have different precisions, ranging from 0 (e.g., 13 for EURO), 1 (e.g., 165.7 for TENA), to 2 (e.g., 72.71 for BONA). These inconsistencies in precision across different regions negatively impact the scientific credibility of the study.
P1 L28: “the lion’s share of total emissions”
While "lion's share" is a colorful and idiomatic expression, it may not be the most appropriate choice for a scientific journal. Scientific writing typically aims for clarity and precision, avoiding figurative language or colloquialisms that might distract from the data or findings being presented.
P1 L29-30: “with marked increases observed in August and September (annual average 441.32 Tg C) compared to other months”
According to Figure 4, OBB emissions in September did not have ‘marked increases’ from that in July (in fact, 2021 July emissions were higher than that in 2021 September). Avoid subjective terms like "marked increases" unless they are supported by the data.
P1 L31: “This surge in carbon emissions is…”
Choose a more neutral term than "surge" to describe the increase in carbon emissions. Perhaps "significant rise" or "notable increase" would be more appropriate.
P1 L32-34: “Fires in savanna grasslands were predominant in the NHAF, contributing to 77%
of emissions during January–April, whereas in the SEAS, woody savanna/shrubs (52%) and tropical forests (23%) were the primary sources.”
This sentence only presents detailed results from this study without any scientific explanation and discussion. I think it should belong to the results section, not here in the abstract.
P2 L40-41: “Forest clearing, accidental fires, firewood burning,agricultural residue burning, peatland burning and straw burning are among the major fire types worldwide”
The fire types listed here are not well organized. ‘Straw burning’ is a type of ‘agricultural residue burning’. It’s redundant to list both items. ‘Accidental fires’ represent one of the fire sources (not types). Also, you forgot to list the burning type that consumes most of the global burned area: savanna/grassland/shrub fires. Please organize the fire types more efficiently and eliminate redundancy.
P2 L44: “However, some regions worldwide are…”
Since there is no clear contrast in the preceding sentences, avoid using "however" here.
P2 L44-46: “...experiencing a notable increase in fire incidents (Richardson et al., 2022), such as, the Amazon rainforest fires (Pivello, 2011), Australian bushfires (Jegasothy et al., 2023), and wildfires in the United States (You and Xu, 2023), which are large–scale fire incidents that occur multiple times annually.”
Remove the comma after "such as". Also please clarify what does “...which are large–scale fire incidents that occur multiple times annually” refer to.
P2 L50-52: “The burned area method demonstrated good accuracy in quantifying larger fire events, which is based on the burned area, the available biomass fuels burned in fields, the fuel-related combustion efficiency, and emission factors.”
Consider changing “the burned area method” to ‘the burned area based fire emissions method”. Also, please clarify what the relative pronoun “which” refers to.
P2 L52-54: “As well as other open-access databases, such as the Global Fire Emissions Database (GFED) and the Fire INventory from NCAR (FINN) (Jiang et al., 2012; van Wees et al., 2022)”
This is not even a complete sentence!
Jiang et al 2012 is not a good reference for FINN and van Wees et al 2022 is not a good reference for GFED.
P2 L57: “the Global Fire Assimilation System (GFAS) (Di Giuseppe et al., 2017).”
Replace Di Giuseppe et al., 2017 with a better reference for GFAS.
P2 L57-58: “this approach has a drawback in that it tends to overestimate emissions during localized fire events.”
Specify what is meant by 'localized fire events' and why the FRP approach tends to overestimate emissions in such cases. Provide more clarity and context.
P2 L60: “the Fengyun–3D (FY–3D) satellite offers spatial resolutions of 250 and 1000m…, which, when compared to MODIS, significantly enhances its capacity…”
For clarity, it might be better to say a satellite ‘has spatial resolutions’ instead of ‘offers spatial resolutions’. The structure of this sentence is also not optimal and needs revision.
P2 L64: “This resulted in an impressive overall accuracy rate”
In scientific writing, it's generally advisable to maintain a tone of objectivity and avoid overly subjective or emphatic language such as ‘impressive’ in this sentence.
P3 L72-73: “Therefore, employing the FY–3D GFR product and allocation approaches for small fires is expected to yield reliable estimates of OBB emissions.”
Strengthen the causal relationship between the preceding sentence and this one (since you are using ‘therefore’ here)
P3 L73-74: “Many studies treat F as a constant based on regional land cover types, neglecting the actual spatial and temporal variability (Wiedinmyer et al., 2011)”
Many recent studies have already explicitly addressed the spatial and temporal resolution of fuel loads.
Methods that utilize fuel load parameterization based on regional land cover types do not necessarily neglect spatial and temporal variability; they simplify the spatial and temporal representation for computational efficiency.
P3 L74-75: “the combustion factor (CF), which represents the proportion of small biomass burned in a fire event, is typically assumed to be constant without considering the fuel status and humidity conditions (Pfeiffer et al., 2013)”
This definition of CF seems different to what I know. Please review the definition of CF to ensure accuracy and clarity.
Pfeiffer et al., 2013, focuses on a fire model for global biomass burning, which may not be the most appropriate reference for the CF approach used in observation-based global emissions calculations.
P4 L98-99: “where Ei (g/m2) represents type i emissions at location x, which is equal to the product of the burning area B (m2) at time t and location x, biomass F (g C/m2) at location x, CF (expressed as a fraction), and the emission factor EF (g/kg) for type i pollutants.”
The units of the variables in Equation 1 do not align: multiplying the units of B, F, CF, and EF does not result in the unit of E.
P4 L100: “FY–3D global fire spot monitoring data based burned area (B)”
Please acknowledge that the active fire spot data is used as a proxy for burned areas in this section. Clarify the difference between these two datasets and the uncertainties resulting from this approximation to provide a more comprehensive understanding.
P4 L101: “ Chines polar–orbiting meteorological satellites.”
Correct the typo "Chines" to "Chinese"
P4 L102-103: “It (FY-3D) is at an altitude of 836 km and was launched on November 15, 2017 and published on may, 2020.”
What do you mean by saying a satellite (FY-3D) was “published”?
‘may’ should be changed to ‘May’.
P4 L106-107: “FY–3D introduces the adaptive threshold and eliminates the limitations by fixed thresholds of MODIS and VIIRS algorithms”
The ‘fixed thresholds’ are not clearly described. There are multiple thresholds used in the spectral and contextual test in the MODIS/VIIRS algorithm. Specify which specific fixed thresholds are being referred to. Provide more detail to enhance understanding.
P4 L111-112: “the far–infrared channel employed in FY–3D has a high resolution of 250 m, higher than MODIS with 1 km, resulting in higher accuracy in big fire detection”
Explain in more detail how the higher resolution of the far-infrared channel in FY–3D may lead to increased accuracy in detecting big fires.
P4 L113: “the FY–3D GFR product achieves an accuracy of 94.0% globally”
Define the metric used to determine accuracy and provide information on the reference datasets. Specify the variables compared and the methodology used to derive the accuracy percentage.
P4 L116: “for accuracy and accuracy without omission”
Define "accuracy without omission" to ensure clarity and understanding.
P4 L126: Table 1
‘((NOAA-20))’ should be ‘(NOAA-20)’;
Explain the values within the parentheses (for TMAX)?
Give a definition for TMAX, SNR, and NEdT
P5 L129-130: “Previous studies on emission inventories based on wildfire areas were mostly used to assess F by defining different fire types in different areas”
Clarify the meaning of the sentence (or rephrase it) for better understanding.
P5 L136-139: “This fusion method combines the high accuracy of ground observation data with wide coverage of satellite data to produce reliable and precise global biomass products. Using this method, it is possible to overcome the limitations of a single data source, thereby enhancing the accuracy and reliability of biomass estimation.”
Tone down the language describing the fusion method (such as ‘effective’, ‘reliable’, ‘precise’) to avoid overconfidence. While the approach of combining different data streams can help mitigate limitations of using a single data source, it may introduce additional uncertainties.
P5 L139: “This study used multi–source data, including NDVI, tree cover (TC), and satellite and observational AGB, to …”
NDVI is never defined in the manuscript.
Again, satellite AGB is a type of observational AGB. So it’s redundant to say ‘satellite and observational AGB’.
P5 L143: “GEE platform”
GEE is not defined.
P5 L144: “so we combined the global aboveground and belowground biomass carbon density maps”
Provide a more detailed description of the global aboveground and belowground biomass carbon density maps to enhance understanding, as they are core datasets for fuel loading used in the study.
P6 L147: Equation 2
Verify the accuracy of Equation 2, as it appears to lead to a discrepancy. For year 2010, this equation lead to 2*AGB, while AGB is defined as AGB data in 2010. I guess there should be an additional coefficient of ½ in the equation.
P6 L149: “TC2010 is the tree cover in 2020”
Confirm the correct year for TC2010, as it appears to be a typo.
P6 L154: “Typically, CF is set as a constant”
Revise to reflect the evolving understanding in recent studies, which often employ parameterizations to account for spatial and temporal variations, rather than assuming a constant CF.
P6 L159: “A major influence on fire discharge in the framework is the surface condition…”
Clarify the terms ‘fire discharge’ and ‘framework’
P6 L159-160: “Different landtypes exhibit different biological qualities and correlations.”
Clarify the term "biological quantities" for better understanding.
P6 L162-163: “reclassified the original 17 classifications, and reclassified the results to
reorganize the subsurface types into seven categories”
Revise for clarity and organization. Consider splitting the sentence for improved readability.
P6 L167-168: “we amalgamated the reclassification outcomes of V3, V4, V5, and V6 into a forest type category, designated V1 and V2 as woodlands, and assigned V7 to crops”
Clarify the two-step process of aggregation for better understanding.
Explain the relationship between grassland and woodland and how the original classifications were aggregated to represent grassland.
Provide rationale for not directly aggregating the MCD12Q1 classifications to the final categories of forest, woodland, and cropland.
P6 L173: “We incorporated the VCI to ascertain fuel moisture conditions”
Define ‘ascertain’ for clarity
P6 L176: Equation 4
Capitalize the variable ‘vci’
P7 L177: Equation 5
Justify the changes made to Equation 5 compared to Equation 10 in Ito and Penner, 2004, to provide clarity on the modifications and their impact on the model.
P7 L178-179: “NDVImax the maximum value of NDVI in the same period in the previous 3 years”
Explain the rationale for using the previous 3 years as the reference period for NDVImax to provide context for the choice of this time frame.
P7 L180-181: “conducted an analysis based on the partitioning provided”
Clarify what is meant by "partitioning provided" to ensure understanding.
P7 L182: “ function fitting was executed”
Whether the ‘function fitting’ is referring to the ‘power function fitting’?
Provide details on the data used for the fitting. I understand VCI was calculated from MODIS NDVI, but where is the MCF data coming from?
P7 L182-183: “For grasslands, the VCI could be directly calculated and utilized.”
Clarify the relevance of including information about grasslands in a paragraph focused on deriving CF for forest fires.
P7 L189: “Here, EF in Tabel 2 was assigned according to the LCT”
Correct the typo "Tabel" to "Table"
Although the data sources in Table 2 have been added in the revised manuscript, a description of the method (e.g., the original data approach, the aggregation algorithm) is still needed here.
P7 L191: “However, other EF measurements were also used when locally measured EF data were not available.”
Specify which dataset contains the locally measured EF data and clarify the meaning of "other EF measurements" for better understanding.
P7 L194-195: “Finally, the EF for the following seven land types of other database were updated”
Clarify the reference data used for updating EF values and provide additional context on the update process for clarity.
I have not provided comments on the 'Results' and 'Discussion' sections in the above list. I encourage the authors to thoroughly review the text, rectify any spelling and grammar errors, improve the flow of transitions between sections, and ensure the use of pertinent citations throughout the manuscript. |
