The North Atlantic and Arctic Oceans are unquestionably major players in the climatic evolution of the Northern Hemisphere and in the history of the meridional overturning circulation of the Atlantic Ocean. The establishment of the modern North Atlantic Water (NAW) transporting heat, salt, and moisture to the Northern Hemisphere has been indicated as one of the main forcing mechanisms for the onset of the Northern Hemisphere glaciation. NAW controls the extent and dynamics of circum-Arctic and circum-North Atlantic ice sheets and sea ice in addition to deep water and brine production. How the ocean system and cryosphere worked during past warmer intervals of high insolation and/or high atmospheric CO2 content is still largely unknown and debated. The required information can only be attained by offshore scientific drilling in high-resolution, continuous, and undisturbed sedimentary sequences identified on the western continental margin of Svalbard (eastern side of the Fram Strait) along the main pathway and northern penetration of the NAW flowing into the Arctic Ocean. The area around Svalbard is very sensitive to climatic variability and it can be considered as a “sentinel of climate change.” Further, the reconstruction of the dynamic history of the marine-based paleo-Svalbard-Barents Sea Ice Sheet is important because it is considered the best available analog to the modern, marine-based West Antarctic Ice Sheet, for which the loss of stability is presently the major uncertainty in projecting future global sea level rise in response to the present global climate warming.
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This content will become publicly available on September 24, 2025
Expedition 403 Preliminary Report: Eastern Fram Strait Paleo-Archive
The North Atlantic and Arctic Oceans are unquestionably major players in the climatic evolution of the Northern Hemisphere and in the history of the meridional overturning circulation of the Atlantic Ocean. The establishment of the modern North Atlantic Water (NAW) transporting heat, salt, and moisture to the Northern Hemisphere has been indicated as one of the main forcing mechanisms for the onset of Northern Hemisphere glaciation. NAW controls the extent and dynamics of circum-Arctic and circum-North Atlantic ice sheets and sea ice in addition to deep water and brine production. How the ocean system and cryosphere worked during past warmer intervals of high insulation and/or high atmospheric CO2 content is still largely unknown and debated. The required information can only be attained by offshore scientific drilling in high-resolution continuous expanded sedimentary sequences identified on the western continental margin of Svalbard (and eastern side of the Fram Strait) along the main pathway and northern penetration of the NAW flowing into the Arctic Ocean. The area around Svalbard is very sensitive to climatic variability and can be considered a sentinel of climate change. Furthermore, the reconstruction of the dynamic history of the marine-based paleo-Svalbard–Barents Sea Ice Sheet is important because it is considered the best available analog to the modern, marine-based West Antarctic Ice Sheet, for which the loss of stability is presently the major uncertainty in projecting future global sea level rise in response to the present global climate warming.
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- Award ID(s):
- 1326927
- PAR ID:
- 10543814
- Publisher / Repository:
- International Ocean Discovery Program
- Date Published:
- Journal Name:
- Preliminary report
- Volume:
- 403
- ISSN:
- 2372-9562
- Subject(s) / Keyword(s):
- International Ocean Discovery Program IODP JOIDES Resolution Expedition 403 Eastern Fram Strait Paleo-Archive Climate and Ocean Change Biosphere Frontiers Earth in Motion Site U1618 Site U1619 Site U1620 Site U1621 Site U1622 Site U1623 Site U1624
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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