Reconstructing past hydrology of eastern Canadian boreal catchments using clastic varved sediments and hydro-climatic modelling: 160 years of fluvial inflows

Gagnon-Poiré, Antoine; Brigode, Pierre; Francus, Pierre; Fortin, David; Lajeunesse, Patrick; Dorion, Hugues; Trottier, Annie-Pier

doi:https://doi.org/10.5194/cp-17-653-2021

Articles | Volume 17, issue 2

https://doi.org/10.5194/cp-17-653-2021

© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/cp-17-653-2021

© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 17, issue 2

Research article

|

25 Mar 2021

Research article |

| 25 Mar 2021

Reconstructing past hydrology of eastern Canadian boreal catchments using clastic varved sediments and hydro-climatic modelling: 160 years of fluvial inflows

Antoine Gagnon-Poiré, Pierre Brigode, Pierre Francus, David Fortin, Patrick Lajeunesse, Hugues Dorion, and Annie-Pier Trottier

Download

Final revised paper (published on 25 Mar 2021)
Supplement to the final revised paper
Preprint (discussion started on 20 Jul 2020)

Interactive discussion

Status: closed

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

- Printer-friendly version

- Supplement

RC1: 'Review of cp-2020-87', Krystopher Chutko, 17 Aug 2020
- AC1: 'response to reviewer # 1', Antoine Gagnon-Poiré, 02 Sep 2020
  - AC3: 'response to reviewer # 1 PDF file', Antoine Gagnon-Poiré, 03 Sep 2020
RC2: 'Reviewer comments cp-2020-87', Anonymous Referee #2, 22 Aug 2020
- AC2: 'response to reviewer #2', Antoine Gagnon-Poiré, 02 Sep 2020
- AC4: 'response to reviewer # 2 PDF file', Antoine Gagnon-Poiré, 04 Sep 2020
RC3: 'Reviewer comments for cp-2020-87', Anonymous Referee #3, 26 Aug 2020
- AC6: 'response to reviewer #3 PDF file', Antoine Gagnon-Poiré, 19 Sep 2020
AC5: 'response to reviewer #3 PDF file', Antoine Gagnon-Poiré, 04 Sep 2020

Peer-review completion

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

ED: Reconsider after major revisions (12 Oct 2020) by Keely Mills

AR by Antoine Gagnon-Poiré on behalf of the Authors (23 Nov 2020) Author's response Manuscript

ED: Referee Nomination & Report Request started (10 Dec 2020) by Keely Mills

RR by Anonymous Referee #2 (30 Dec 2020)

Suggestions for revision or reasons for rejection

The manuscript by Gagnon-Poire and co-authors entitled ‘Reconstructing past hydrology of eastern Canadian boreal catchments using clastic varved sediments and hydro-climatic modeling: 160 years of fluvial inflows’ has been revised according to reviewer’ comments and a detailed point-by-point response to reviewer comments is presented. Most comments are adequately considered by the authors, but there are still two points that could be better clarified.
First, I agree to the argument that by pooling more than one sediment record local disturbances of the sediment record might be minimized and I appreciate especially the approach to combine a distal and proximal core for the part of the lake influenced by the Naskaupi (NAS-1 and 2). However, it would have been logical to apply the same approach with a distal and a proximal core also for the Beaver River in order to get both parts of the large catchment similarly represented by sediment records. In this respect, it should be clarified why only one core representing the Beaver is included in the analyses and how this different representation of catchments in sediment records influences the analyses.
Second, the effect of the Naskaupi River diversion on sedimentation in the NAS cores as described in lines 670-687 in the manuscript still is not entirely clear. I understood that sedimentation increased due to more sediments available in the catchment due to the changes caused by constructions. It is also stated that the NAS-1 site became ‘more sensitive to maximum discharge variations in spring than mean annual discharges’ (lines 675-676). This would make sense, but apparently this applies only for parts of the spring runoff because ‘the capacity of early spring discharge to transport fine sediments… decreases along with the decrease in water supplies’. This apparent contradiction and differentiation in ‘early spring’ and ‘spring’ should be better explained. Furthermore, the different behavior of site NAS-2, where sediment input declined after 1971 in contrast to NAS-1 where it increased, could be better explained. Is that due to the lower transport capacity of the discharge and does it mean that the additional sediment is mainly accumulated on the delta, thus changing the entire delta geometry?

Hide

ED: Publish subject to minor revisions (review by editor) (14 Jan 2021) by Keely Mills

AR by Antoine Gagnon-Poiré on behalf of the Authors (21 Jan 2021) Author's response Author's tracked changes Manuscript

ED: Publish as is (07 Feb 2021) by Keely Mills

AR by Antoine Gagnon-Poiré on behalf of the Authors (16 Feb 2021) Manuscript

Short summary

A very high quality 160-year-long annually laminated (varved) sediment sequence of fluvial origin was recently discovered in an especially deep lake in Labrador. Each varve represents 1 hydrological year. A significant relation between varves' physical parameters (i.e., thickness and grain size extracted from each annual lamination) and river discharge instrumental observations provided the opportunity to develop regional discharge reconstructions beyond the instrumental period.