The Circum-Arctic Sediment Carbon Database — Carbon, nitrogen and isotopes in sediment cores of the Arctic Ocean

Jannik Martens, Evgeny Romankevich, Igor Semiletov, Birgit Wild, Bart van Dongen, Jorien Vonk, Tommaso Tesi, Natalia Shakhova, Oleg V. Dudarev, Denis Kosmach, Alexander Vetrov, Leopold Lobkovsky, Nikolay Belyaev, Robie Macdonald, Anna J. Pieńkowski, Timothy I. Eglinton, Negar Haghipour, Salve Dahle, Michael L. Carroll, Emmelie K.L. Åström, Jacqueline M. Grebmeier, Lee W. Cooper, Göran Possnert, Örjan Gustafsson

This dataset is part of the Circum-Arctic Sediment Carbon Database (CASCADE) and contains data for sediment cores across the Arctic Ocean, which are divided into three depositional time scales: centennial, millennial and glacial.

This dataset permits studies of past biogeochemical cycling and sediment carbon budgets in the Arctic Ocean using measured organic carbon (OC) concentrations, total nitrogen (TN) concentrations, and OC isotopes (δ¹³C, Δ¹⁴C) in sediment cores.

The dataset includes data from the published literature and yet unpublished data.

Citation

Jannik Martens, Evgeny Romankevich, Igor Semiletov, Birgit Wild, Bart van Dongen, Jorien Vonk, Tommaso Tesi, Natalia Shakhova, Oleg V. Dudarev, Denis Kosmach, Alexander Vetrov, Leopold Lobkovsky, Nikolay Belyaev, Robie Macdonald, Anna J. Pieńkowski, Timothy I. Eglinton, Negar Haghipour, Salve Dahle, Michael L. Carroll, Emmelie K.L. Åström, Jacqueline M. Grebmeier, Lee W. Cooper, Göran Possnert, Örjan Gustafsson (2021) The Circum-Arctic Sediment Carbon Database — Carbon, nitrogen and isotopes in sediment cores of the Arctic Ocean. Dataset version 2. Bolin Centre Database. https://doi.org/10.17043/cascade-sediment-cores-2

References

Martens J, Romankevich E, Semiletov I, Wild B, van Dongen B, Vonk J, Tesi T, Shakhova N, Dudarev OV, Kosmach D, Vetrov A, Lobkovsky L, Belyaev N, Macdonald RW, Pieńkowski AJ, Eglinton TI, Haghipour N, Dahle S, Carroll ML, Åström EKL, Grebmeier JM, Cooper LW, Possnert G, Gustafsson Ö (2021) CASCADE – The Circum-Arctic Sediment CArbon DatabasE. Earth Syst Sci Data 13:2561⁠ – ⁠2572. https://doi.org/10.5194/essd-13-2561-2021

Data description

Depositional time scales

Sediment cores are distinguished by three depositional time scales as follows:

1. Centennial scale cores (core scale 1) in upper sediments of the Arctic Ocean, e.g., multi corer, Gemini corer, box corer, van Veen grab sampler, other short gravity corers up to 1 m length.
2. Millennial scale cores (core scale 2) of shelf sediments roughly covering the depositional time frame from the late Holocene to the last glacial/interglacial transition, by e.g., piston corer, long gravity corer, kasten corer.
3. Glacial cycles scale cores (core scale 3) from the continental slopes or the deeper Arctic Ocean basins covering periods from earlier than the Last Glacial Maximum, including e.g. drill coring on the Circum-Arctic shelves or deep-sea piston cores.

Data sheets for sediment cores

Three depositional time scales are distinguished for the dataset of sediment cores (see criteria above), which are organized as three different data tables. We, however, also provide one summary table with all core scales represented in one file. Each core scale is available as Excel spreadsheet (.xslx) and as tab-separated text (.txt) file:

• CASCADEcorescale1_v2.xlsx
• CASCADEcorescale1_v2.txt
• CASCADEcorescale2_v2.xlsx
• CASCADEcorescale2_v2.txt
• CASCADEcorescale3_v2.xlsx
• CASCADEcorescale3_v2.txt
• CASCADEcores_v2.xlsx
• CASCADEcores_v2.txt

Data sheet structure

As for surface sediments, all data and meta data for each core subsample and measurement are organized as columns in each data table. Each row in the CASCADE data sheets for sediment cores represents one subsample from a sediment core at an oceanographic station that was analyzed for one or several carbon parameters. The data sheet for sediment cores also includes a column for the sampling depth of core subsamples in cm below the sediment surface. Hence, multiple subsamples from one core are organized as multiple subsamples in the data sheet, which share the same geospatial information (lat, lon) but represent different sampling depth.

Columns for ID, depth and georeference

1. CASCADE entry ID
2. Sample code (as reported by data source)
3. Latitude (decimal degrees)
4. Longitude (decimal degrees)
5. Mean sample depth below sea floor (cm)
6. Water depth (m b.s.l.)
7. Expedition or vessel name
8. Sampling year

Carbon and Nitrogen (CN) data

9. OC (%)
10. TN (%)
11. OC/TN

Carbon isotopes

12. δ¹³C (‰ VPDB)
13. Δ¹⁴C (‰)

References

14. Citation of CN data
15. Citation of δ¹³C data
16. Citation of Δ¹⁴C data

Quality parameter and meta information

17. Sediment sampler (e.g. grab sampler, multi corer, etc)
18. Sample storage (0 for unknown, 1 for frozen, 2 for refrigerated)
19. CN measurement (method of analysis)
20. ¹³C measurement (method of analysis)
21. AMS label

Comments

Please cite the companion paper in ESSD and the database when using the CASCADE.

The CASCADE is guided and continuously curated by scientists at the Bolin Centre for Climate Change

• Örjan Gustafsson
• Jannik Martens
• Matthias Brakebusch

Version history

Version 2

Minor corrections and improvements of the dataset based on reviewer comments.

Version 1

Initial release.