Lessons Learned from Applying Adaptation Pathways in Heatwave Risk Management in Antwerp and Key Challenges for Further Development
Round 1
Reviewer 1 Report
This study presents diagrams in the form of black and white figures. Figures 9 and 14 are however described in color. References to figures do not appear in the text. The simulations are not explained. Apparently, there is no measurement campaign or physical modeling.
Author Response
We would like to thank the reviewer 1 for his/her time and valuable comments. We proceed to improve the manuscript accordingly.
Response to Reviewer 1 Comments.
The manuscript has undergone through profesional English editing
Point 1. This study presents diagrams in the form of black and white figures. Figures 9 and 14 are however described in color.
Response 1: Thank you for pointing the colouring errors in some of the Figures as they were originally in colour. We have now updated the Figures so that all are visualized in colour.
Point 2. References to figures do not appear in the text. The simulations are not explained
Response 2: Reference to Figure 4 was not present and has now been included in the text. After the revision, in Page 17, references to Figures 11, 12, 13 were not updated.
Point 3: Apparently, there is no measurement campaign or physical modeling
Response 3:
We have created a new subsection (2.1) in materials and methods to shortly describe the input information (urban climate modelling and building simulations) for the development of adaptation pathways. The information is well described in Climatic Change (2017) 144:721–735. DOI 10.1007/s10584-017-2058-1
Furthermore, we have included some few more references and improved the research questions we are aiming to solve/present.
Reviewer 2 Report
The paper's objective is to present the key steps and decisions adopted to transfer the adaptation pathway approach to the local context in a case study, Antwerp. The methodology for designing climate Adaptation Pathways is also presented with the selection of the best alternative options for climate heat wave risk. The lessons learned and challenges of the proposed approach for further development are discussed.
The paper seems well structured but some fundamental issues the proposed methodology should be more detailed for a better comprehension of the paper.
Page 2, Line 89: please insert the reference. The same at page 7 line 269, page 5 line 181 and 182/ 183, page 9 line 325, page 13 line 377, page 14 line 400, page 15 line 413, page 17 line 436.
Page 4, sect. 3.1.2: about the WBGT it is essential to be more detailed. The WBGT index is widely used for estimating the heat stress potential of industrial environments (see ASHRAE), so references shall be introduced for better detail this proposal.
Moreover, information on the RAMSES methodology for calculating LWH (%) should be proposed for better clarify the connection between the buildings parameters and LWH.
Page 6: sect. 3.1.3 Adaptation Objectives. Perhaps the proposed values for temperatures could be revised. Are you sure that the value of 5.1°C is so different to 5.09°C? How it could be possible to measure these values with defined accuracy and constant in time?
These temperatures values are referred to air, surfaces or WBGT? How the radiation contribution it is considered in the model?
The results are analyzed as function of air temperature: why?
Page 7, fig.3: please revise the caption. The figure is not colored.
Page 10, Fig.5: the differences in LHW(%) between figures a), b) and c) aren't so evident... Please try to improve the description.
Red color is not readable also for Fig. 9 (page 14)
References: Some citations (nr 27, 33 and 36) could be better indicated (i.e. editor, journal, report,...)
Author Response
We would like to thank Reviewer 2 for your valuable comments. We have proceed to improve the manuscript accordingly.
Point 1. The paper seems well structured but some fundamental issues the proposed methodology should be more detailed for a better comprehension of the paper.
Response 1: Thank you for your comment. We have created a new subsection (2.1) in materials and methods to shortly describe the input information (urban climate modelling and building simulations) for the development of adaptation pathways. The information is well described in Climatic Change (2017) 144:721–735. DOI 10.1007/s10584-017-2058-1. We hope the methodology is clearer now.
Point 2. Page 2, Line 89: please insert the reference. The same at page 7 line 269, page 5 line 181 and 182/ 183, page 9 line 325, page 13 line 377, page 14 line 400, page 15 line 413, page 17 line 436.
Response 2: Thank you for your input on extra places where references would be beneficial. However, it seems there has been some sort of problem that the referred lines often do not correspond to the page and the referred lines do not seem to need any reference.
Point 3:Page 4, sect. 3.1.2: about the WBGT it is essential to be more detailed. The WBGT index is widely used for estimating the heat stress potential of industrial environments (see ASHRAE), so references shall be introduced for better detail this proposal. Moreover, information on the RAMSES methodology for calculating LWH (%) should be proposed for better clarify the connection between the buildings parameters and LWH.
Response 3: As previously mention, a section has been included in methods and material to describe better the calculation and use of WBGT and LWH.
Point 4. Page 6: sect. 3.1.3 Adaptation Objectives. Perhaps the proposed values for temperatures could be revised. Are you sure that the value of 5.1°C is so different to 5.09°C? How it could be possible to measure these values with defined accuracy and constant in time?
Response 4: Thank you for the remark. The given values are obtained after a substraction between the projected temperatures for the future and the thresholds defined by stakeholders. However, it is true that it does not make sense to include such an accurate value. Thus, temperatures have been updated with just one decimal
Point 5. These temperatures values are referred to air, surfaces or WBGT? How the radiation contribution it is considered in the model?
Response 5: Temperatures are referred to air temperature. We have accordingly include “air temperature” to avoid confusion. The radiation contribution was not the focus of this paper, but planning. However, we have referred to a RAMSES linked output: Climatic Change (2017) 144:721–735. DOI 10.1007/s10584-017-2058-1 where further information can be found.
Point 6. The results are analyzed as function of air temperature: why?
Response 6. Thank you for your comment. We have rephase it to make it clearer
The results are analyzed in LWH (%) when the adaptation pathway aims at adapting indoor conditions.
The results are analyzed in air temperature when the adaptation pathway aims at adapting outdoor urban conditions
Please, see section 3.1.3 as example. A few words have been included to explicitly mention what i is outdoor and indoor objectives
Point 7. Page 7, fig.3: please revise the caption. The figure is not colored.
Response 7. Thank you for pointing out this error. Originally a coloured figure was used. Figure 3 is now included in colour to facilitate reading
Point 8. Page 10, Fig.5: the differences in LHW(%) between figures a), b) and c) aren't so evident... Please try to improve the description. Red color is not readable also for Fig. 9 (page 14)
Response 8. Figures have been improved and Figure 5 description has been updated.
Point 9.References: Some citations (nr 27, 33 and 36) could be better indicated (i.e. editor, journal, report,...)
Response 9. We completely agree with the reviewer as the reference editor seem that has not entered correctly the references. References have been updated.
Reviewer 3 Report
This paper describes adaptation pathways for heat wave management in the Belgian city of Antwerp. The paper is well structured and well written. Authors acknowledge high remaining uncertainties that cannot be reduced and propose a stepwise, iterative approach that stays flexible enough to calibrate with additional future data. Indeed, the set of drivers for political action is complex and should include various fields, not just climate change. Society benefits most from “no regret meadures”, i.e. focus initially on solutions regardless of uncertain future developments, the “low hanging fruits”.
In my opinion, the authors could make their arguments even stronger by stressing that future summer climate of Antwerp is likely to be similar as in some locations further south already today. Four of the authors are from Spain where heat waves today are probably longer and more intense than in Antwerp. How do Spanish cities cope with these heat waves? How did Spanish society adapt to this climate over the centuries? What can northern European cities learn from their southern European neighbours? How does heat impact productivity and mortality in e.g. Spain? What are the main adaptation strategies? Historically it was the extended lunchtime break (“siesta”) and re-arrangement of working times into cooler parts of the day. Later, air condition was installed and the work schedule was more flexible again. If all households and work places in Antwerp were to install air condition, would this help? How would this impact loss of worktime and mortality? Some of this is already mentioned in the Results section of the paper. But some direct reference to southern European strategies would be beneficial.
Tables 1 and 2 list data for climate projections up to 2100. These values involve large uncertainties, largely controlled by unknown emission path (political decisions) and climate sensitivity (scientific uncertainty). But authors state only a single value, e.g. for the number of heatwaves. In reality this should be a wide range. It is ok to work with a mean number for schematic purposes. But some sort of error bars or uncertainty range description should be mentioned.
Lines 217-220: Where do these temperatures come from, reference? 10°C warming even for the “far future” is unlikely. The IPCC in AR6 has just reduced the upper limit of the likely range of the climate sensitivity from 4.5 to 4.0°C warming per CO2 doubling. The CMIP6-models have turned out to be too hot and shall not been used for future temperature modelling. Please also note that similar temperatures as today already occurred 1000 years ago during the Medieval Climate Anomaly, probably with similar frequency and intesity of heat waves as today. How did Medieval people deal with the heat in Europa? See e.g. Lüning et al. doi: 10.1029/2019PA003734.
Climate change will likely increase the number of heat waves, but also reduce the number of cold waves. It would be good if authors can say a few words about the benefits of fewer cold waves and their potential savings for countries. Can some of the saved funds be re-directed to adapting to heat waves?
I noticed error messages in line 89 and others. Please check what went wrong here.
Summed up, a very good manuscript after a little bit of extra work.
Author Response
We would like to thank Reviewer 3 for your time and valuable comments. We have proceed to improve the manuscript accordingly.
Point 1. In my opinion, the authors could make their arguments even stronger by stressing that future summer climate of Antwerp is likely to be similar as in some locations further south already today. Four of the authors are from Spain where heat waves today are probably longer and more intense than in Antwerp. How do Spanish cities cope with these heat waves? How did Spanish society adapt to this climate over the centuries? What can northern European cities learn from their southern European neighbours? How does heat impact productivity and mortality in e.g. Spain? What are the main adaptation strategies? Historically it was the extended lunchtime break (“siesta”) and re-arrangement of working times into cooler parts of the day. Later, air condition was installed and the work schedule was more flexible again. If all households and work places in Antwerp were to install air condition, would this help? How would this impact loss of worktime and mortality? Some of this is already mentioned in the Results section of the paper. But some direct reference to southern European strategies would be beneficial.
Response 1: Thank you for the interesting comment by the reviewer. It is indeed a very valid and interesting research question. The reviewer is right that northern country in Europe will present more similar summers to what historical has been in the south of Europe. Despite the points are very valid the focus of the work is more related on the presentation of a valid planning approach with a step-by-step methodology and its application to a case study. The benchmarking of the adaptation option is very interesting but may introduce a complexity to the manuscript that may lead to loose the focus of it. Adaptation options often have a high context influence. For example, in south of Spain (as well as in e.g. Greece), a traditional adaptation mechanism has been to have “white villages” what we now technically call cool roofs/façades/materials, but that it is not easily applicable to today’s context in many European Cities. Thus the paper only considers those that were feasible in Antwerp (Figure 3)
Point 2. Tables 1 and 2 list data for climate projections up to 2100. These values involve large uncertainties, largely controlled by unknown emission path (political decisions) and climate sensitivity (scientific uncertainty). But authors state only a single value, e.g. for the number of heatwaves. In reality this should be a wide range. It is ok to work with a mean number for schematic purposes. But some sort of error bars or uncertainty range description should be mentioned.
Response 2: Thank you for your comment. It is true that climate projections using different models have an associated uncertainty. However, to avoid confusion we have updated Table’s 1 title to better represent the reviewers’s point. Table 2 includes “threshold” temperatures associated to Antwerp’s Federal Plan, thus no uncertainty applies here
Point 3. Lines 217-220: Where do these temperatures come from, reference? 10°C warming even for the “far future” is unlikely. The IPCC in AR6 has just reduced the upper limit of the likely range of the climate sensitivity from 4.5 to 4.0°C warming per CO2 doubling. The CMIP6-models have turned out to be too hot and shall not been used for future temperature modelling. Please also note that similar temperatures as today already occurred 1000 years ago during the Medieval Climate Anomaly, probably with similar frequency and intesity of heat waves as today. How did Medieval people deal with the heat in Europa? See e.g. Lüning et al. doi: 10.1029/2019PA003734.
Response 3: Thank you for your comment. The work does not refer to a 10°C warming, but the need to reduce up to 10°C to avoid the system to be no longer effective in keeping the population safe due to heat.
Point 4. Climate change will likely increase the number of heat waves, but also reduce the number of cold waves. It would be good if authors can say a few words about the benefits of fewer cold waves and their potential savings for countries. Can some of the saved funds be re-directed to adapting to heat waves?
Response 4: Thank you for your comment. We have tried to make the climate change statement stronger by incorporating one extra paragraph in the introduction.
Point 5. I noticed error messages in line 89 and others. Please check what went wrong here.
Response 5: The manuscript has gone though profesional english editing
Point 6. Summed up, a very good manuscript after a little bit of extra work.
Response 6.Thank you for your time and we appreciate your constructive revision.
Round 2
Reviewer 1 Report
The main commentaries have been taken into account.
Author Response
Thank you again for this second review.
Reviewer 2 Report
please revise the equation in line 171.
Caption of Fig.3 is not in the same page that the figure
No further comments
Author Response
Dear Reviewer 2,
Thank you for identifying a typo error. Equation has been corrected.
Captions have been revised so that they are in the same page ( we have checked using simple revision mode).
Best regards,
Saioa
