Inferring the anthropogenic NO<sub><i>x</i></sub> emission trend over the United States during 2003–2017 from satellite observations: was there a flattening of the emission trend after the Great Recession?

Li, Jianfeng; Wang, Yuhang

doi:https://doi.org/10.5194/acp-19-15339-2019

Articles | Volume 19, issue 24

https://doi.org/10.5194/acp-19-15339-2019

© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/acp-19-15339-2019

© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 19, issue 24

Research article

|

17 Dec 2019

Research article |

| 17 Dec 2019

Inferring the anthropogenic NO_x emission trend over the United States during 2003–2017 from satellite observations: was there a flattening of the emission trend after the Great Recession?

Jianfeng Li and Yuhang Wang

Download

Final revised paper (published on 17 Dec 2019)
Supplement to the final revised paper
Preprint (discussion started on 16 Jul 2019)
Supplement to the preprint

Interactive discussion

Status: closed

AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment

- Printer-friendly version

- Supplement

SC1: 'A study on long-term tropospheric NO2 trends', Aristeidis Georgoulias, 16 Jul 2019
- AC1: 'Responses to Georgoulias', Jianfeng Li, 28 Jul 2019
- AC2: 'Responses to Georgoulias2', Jianfeng Li, 09 Oct 2019
- AC3: 'revised manuscript', Jianfeng Li, 10 Oct 2019
RC1: 'Nonlinearities in interpreting NOx emissions', Anonymous Referee #1, 13 Aug 2019
- AC4: 'Responses to reviewer #1', Jianfeng Li, 10 Oct 2019
- AC5: 'revised manuscript', Jianfeng Li, 10 Oct 2019
RC2: 'Review of Li and Wang paper', Anonymous Referee #2, 16 Aug 2019
- AC6: 'responses to reviewer #2', Jianfeng Li, 10 Oct 2019
- AC7: 'revised manuscript', Jianfeng Li, 10 Oct 2019

Peer-review completion

AR: Author's response | RR: Referee report | ED: Editor decision

AR by Jianfeng Li on behalf of the Authors (09 Oct 2019) Author's response Manuscript

ED: Publish subject to minor revisions (review by editor) (10 Oct 2019) by Andreas Richter

Dear Jianfeng Li,

I’m pleased to accept your revised manuscript "Inferring the anthropogenic NOx emission trend over the United States during 2003–2017 from satellite observations: Was there a flattening of the emission trend after the Great Recession?" for publication in ACP subject to minor revisions.

Most of the points raised by the reviewers have been answered and addressed in the revised version, but I have some additional comments and suggestions listed below. Please consider them carefully and provide a point by point reply together with the revised final manuscript.

Best regards,

Andreas Richter

• In my opinion, a weakness of this work is the lack of separation between chemical and other factors resulting in non-linearities. In the manuscript, chemical non-linearities are often mentioned but they probably play only a minor role compared to the main factor, the relative contribution of anthropogenic to total NOx emissions in a given grid cell. If that’s possible, it would therefore be good to add some information on which fraction of the observed non-linearity is really due to chemical non-linearities.

• Abstract, line 17: “non-linearity in the emission-TVCD relationship” should be “anthropogenic emission”

• Introduction, line 31: “unfavourable to climate change” – please rephrase

• Introduction, line 35: now soil emissions are mentioned specifically making the statement more correct but highlighting that these numbers without an estimate for lightning NOx are incomplete. Please add an estimate for lightning.

• Line 64: paragraph starts with chemical non-linearities, suggesting that the following discussion is about chemistry while I would argue that most of the following observations are explained by the relative contribution of anthropogenic emissions, not chemical non-linearities.

• Line 84: again, chemical non-linearity is mentioned explicitely but I find this misleading.

• Line 204: “in part” – are there any other possible reasons for the non-linearity?

• Line 251: I can’t really see the difference in variability between the two overpass times…

• Line 256: … and even if it were present, why is that indicative of chemical non-linearity?

Hide

AR by Jianfeng Li on behalf of the Authors (21 Oct 2019) Author's response Manuscript

ED: Publish as is (22 Oct 2019) by Andreas Richter

AR by Jianfeng Li on behalf of the Authors (30 Oct 2019)

Post-review adjustments

AA: Author's adjustment | EA: Editor approval

AA by Jianfeng Li on behalf of the Authors (03 Dec 2019) Author's adjustment

EA: Adjustments approved (04 Dec 2019) by Andreas Richter

Download

Article (8832 KB)
Full-text XML

Short summary

NO₂ tropospheric vertical columns (TVCDs) and surface concentrations are widely used proxies for NO_x emission variations. Through model and observation analyses, we find that satellite NO₂ TVCDs provide much better information on anthropogenic NO_x emission variations over urban than rural regions. NO₂ surface observations, satellite column datasets, and EPA anthropogenic NO_x emissions show consistent annual variations over urban regions of the United States with a continuous decrease after 2011.

Inferring the anthropogenic NOx emission trend over the United States during 2003–2017 from satellite observations: was there a flattening of the emission trend after the Great Recession?

Download

Interactive discussion

Peer-review completion

Post-review adjustments

Inferring the anthropogenic NO_x emission trend over the United States during 2003–2017 from satellite observations: was there a flattening of the emission trend after the Great Recession?