Deglacial export of pre-aged terrigenous carbon to the Bay of Biscay
-
Published:2024-01-16
Issue:1
Volume:20
Page:121-136
-
ISSN:1814-9332
-
Container-title:Climate of the Past
-
language:en
-
Short-container-title:Clim. Past
Author:
Queiroz Alves EduardoORCID, Wong WanyeeORCID, Hefter JensORCID, Grotheer HendrikORCID, Tesi Tommaso, Gentz Torben, Zonneveld Karin, Mollenhauer GesineORCID
Abstract
Abstract. The last deglaciation is the most recent relatively well-documented period of pronounced and fast climate warming, and, as such, it holds important information for our understanding of the climate system. Notably, while research into terrestrial organic carbon reservoirs has been instrumental in exploring the possible sources of atmospheric carbon dioxide during periods of rapid change, the underlying mechanisms are not fully understood. Here we investigate the mobilization of organic matter to the Bay of Biscay, located in the north-eastern Atlantic Ocean off the coasts of France and Spain. Specifically, we focus on the area that was the mouth of the Channel River during the last deglaciation, where an enhanced terrigenous input has been reported for the last glacial–interglacial transition. We conducted a comprehensive suite of biomarker analyses (e.g. n-alkanes, hopanes and n-alkanoic acids) and isotopic investigations (radiocarbon dating and δ13C measurements) on a high-resolution sedimentary archive. The present study provides the first direct evidence for the fluvial supply of immature and ancient terrestrial organic matter to the core location. Moreover, our results reveal the possibility of permafrost carbon export to the ocean, driven by processes such as deglacial warming and glacial erosion. These findings are consistent with observations from other regions characterized by present or past permafrost conditions on land, which have shown that permafrost thaw and glacial erosion can lead to carbon remobilization, potentially influencing atmospheric carbon dioxide levels.
Funder
Alexander von Humboldt-Stiftung Deutsche Forschungsgemeinschaft
Publisher
Copernicus GmbH
Reference151 articles.
1. Andersen, K. K., Azuma, N., Barnola, J. M., Bigler, M., Biscaye, P., Caillon, N., Chappellaz, J., Clausen, H. B., Dahl-Jensen, D., Fischer, H., Flückiger, J., Fritzsche, D., Fujii, Y., Goto-Azuma, K., Grønvold, K., Gundestrup, N. S., Hansson, M., Huber, C., Hvidberg, C. S., Johnsen, S. J., Jonsell, U., Jouzel, J., Kipfstuhl, S., Landais, A., Leuenberger, M., Lorrain, R., Masson-Delmotte, V., Miller, H., Motoyama, H., Narita, H., Popp, T., Rasmussen, S. O., Raynaud, D., Rothlisberger, R., Ruth, U., Samyn, D., Schwander, J., Shoji, H., Siggard-Andersen, M. L., Steffensen, J. P., Stocker, T., Sveinbjörnsdóttir, A. E., Svensson, A., Takata, M., Tison, J. L., Thorsteinsson, T., Watanabe, O., Wilhelms, F., and White, J. W.: High-resolution record of Northern Hemisphere climate extending into the last interglacial period, Nature, 431, 147–151, 2004. a 2. Antoine, P., Coutard, J. P., Gibbard, P., Hallegouet, B., Lautridou, J. P., and Ozouf, J. C.: The Pleistocene rivers of the English Channel region, J. Quaternary Sci., 18, 227–243, 2003. a, b 3. Arz, H. W., Pätzold, J., and Wefer, G.: Climatic changes during the last deglaciation recorded in sediment cores from the northeastern Brazilian Continental Margin, Geo-Mar. Lett., 19, 209–218, 1999. a, b 4. Aufdenkampe, A. K., Mayorga, E., Raymond, P. A., Melack, J. M., Doney, S. C., Alin, S. R., Aalto, R. E., and Yoo, K.: Riverine coupling of biogeochemical cycles between land, oceans, and atmosphere, Front. Ecol. Environ., 9, 53–60, 2011. a 5. Avis, C. A., Weaver, A. J., and Meissner, K. J.: Reduction in areal extent of high-latitude wetlands in response to permafrost thaw, Nat. Geosci., 4, 444–448, 2011. a
|
|