FLOWSA: A Python Package Attributing Resource Use, Waste, Emissions, and Other Flows to Industries

Round 1

Reviewer 1 Report

Overall, this is a well-written and interesting article, presenting a relevant tailored approach/tool to associate flows with sectors. It seems to fit very well in the scope of the special issue. A major issue is the lack in contextualization and addressing of underlying/associated scientific issues. See the major comments below. Hence, I advise for a major revision of this work.

Major comments

In the special issue, related articles have been published. A very similar one to your work is the article on stEWI (https://0-www-mdpi-com.brum.beds.ac.uk/2076-3417/12/7/3447), also authored by some of the authors. It is crucial to position and differentiate your work from these others better to highlight the added value of your work. Especially the article on stEWI seems at first hand very similar, so please be clear on this also in the introduction.

IO-models, are converted from supply and use-tables. A conversion to sector-by-sector is straightforward and your model can directly serve that (your FBS, if I understood well). However, an important aspect in the conversion for LCA is to convert to product-by-product versions (is this what you mean with FBA?), which necessitates addressing of multifunctionality. A further step for IO-LCA or hybrid-LCA is then also the addressing of multifunctionality (Majeau‐Bettez et al., 2018, 2016; Schaubroeck et al., 2021; Suh et al., 2010), which does not seem addressed in your work. What if sectors provide multiple products from different product groups? Moreover, what about the balancing of flows? At the end, there is a citation of a future article. Will this then be discussed there?

Specify what you mean with “activity” of FBA? Is this a process or a good? This is very crucial to understand in light of the link with LCA and whether you have dealt with the multifunctionality issue.

This exercise seems to be tailored to the US, or is it not? Discuss how your approach can be applied in other countries. Keep in mind that for certain products, from a life cycle perspective, impacts are outside of the US. Hence, applicability in other countries is also useful for the US from a consumption-perspective. Elaborate on this all in the discussion.

In a more broader regard, has this type of tool not already been developed in literature? If not, this would be the first of its kind, which would be relevant to point out.

You mention: “Several FBS datasets are generated 340 by importing emission and waste generation inventory data from the USEPA LCA tool, 341 the Standardized Emission and Waste Inventories (StEWI), rather than directly importing 342 data from USEPA datasets (Young et al. 2022)”. Then the only addition seems to be the consideration of resources? This again stresses the need to better distinguish between your work and that of Young et al. Present perhaps an example of what data looks like in StEWI and then how it looks like after processing in FLOWSA. Overall, it might be interesting to take one specific flow and show how it is processed or developed through all the different steps and all the different tools.

On which basis are sectors and activities defined? Are these predefined or generated based on data source information? Please elaborate.

The article seems to focus on environmental flows, but could this also not readily be used for social flows and social LCA. You already cover “employment”. Please elaborate on this.

Minor comments

The reference notation style in the manuscript is not according to the journal. Please adapt

Introduction

Explain basic notions better and refer to key references. For example explain LCA

Methods

Why are chemicals an elementary flow? They are produced by the industry. Or do you mean only chemical emissions or spills?

Majeau‐Bettez, G., Dandres, T., Pauliuk, S., Wood, R., Hertwich, E., Samson, R., Strømman, A.H., 2018. Choice of Allocations and Constructs for Attributional or Consequential Life Cycle Assessment and Input-Output Analysis. J. Ind. Ecol. 22, 656–670. https://0-doi-org.brum.beds.ac.uk/10.1111/jiec.12604

Majeau‐Bettez, G., Wood, R., Hertwich, E.G., Strømman, A.H., 2016. When Do Allocations and Constructs Respect Material, Energy, Financial, and Production Balances in LCA and EEIO? J. Ind. Ecol. 20, 67–84. https://0-doi-org.brum.beds.ac.uk/10.1111/jiec.12273

Schaubroeck, T., Gibon, T., Igos, E., Benetto, E., 2021. Sustainability assessment of circular economy over time: Modelling of finite and variable loops & impact distribution among related products. Resour. Conserv. Recycl. 168, 105319. https://0-doi-org.brum.beds.ac.uk/10.1016/j.resconrec.2020.105319

Suh, S., Weidema, B., Schmidt, J.H., Heijungs, R., 2010. Generalized Make and Use Framework for Allocation in Life Cycle Assessment. J. Ind. Ecol. 14, 335–353. https://0-doi-org.brum.beds.ac.uk/10.1111/j.1530-9290.2010.00235.x

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

I am happy for reviewing your manuscript which was very interesting to me. It is certainly an interesting topic. Specifically, this paper developed the open-source Flow Sector Attribution (FLOWSA) Python package to address the challenges surrounding attributing flows to US industrial and final use sectors. Models capture flows drawn from or released to the environment by sectors, as well as flow transfers between sectors. Some of the issues that need to be addressed are as follows.

Please describe the scientific contribution of this study.

The conclusions are desirable to be elucidated in detail.

Can FLOWSA broaden the scope of his applications? For example, applying it to similar studies in other countries.

Comments for author File: Comments.docx

Author Response

Please see the attachment. 

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors have addressed the comments adequately