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Abstract Winter surface air temperature (Tas) over the Barents–Kara Seas (BKS) and other Arctic regions has experienced rapid warming since the late 1990s that has been linked to the concurring cooling over Eurasia, and these multidecadal trends are attributed partly to internal variability. However, how such variability is generated is unclear. Through analyses of observations and model simulations, we show that sea ice–air two-way interactions amplify multidecadal variability in sea-ice cover, sea surface temperatures (SST) and Tas from the North Atlantic to BKS, and the Atlantic Meridional Overturning Circulation (AMOC) mainly through variations in surface fluxes. When sea ice is fixed in flux calculations, multidecadal variations are reduced substantially (by 20–50%) not only in Arctic Tas, but also in North Atlantic SST and AMOC. The results suggest that sea ice–air interactions are crucial for multidecadal climate variability in both the Arctic and North Atlantic, similar to air-sea interactions for tropical climate.
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Western Siberia experienced rapid shifts in moisture source and summer water balance during the last deglaciation and early Holocene
ABSTRACT The Russian Arctic is an extensive region, with relatively few long‐duration paleoclimate reconstructions compared to other terrestrial Arctic regions. We present a 24 000‐year reconstruction of climate in the Polar Ural Mountains usingn‐alkanoic acid hydrogen isotopes from Lake Bolshoye Shchuchye. Major last deglaciation climate changes in the North Atlantic are present in this record, including transitions associated with the Bølling–Allerød, Younger Dryas and Holocene. However, the magnitude of the last deglaciation isotopic shifts at Bolshoye Shchuchye are small relative to the North Atlantic, and are dwarfed by a shift to2H‐enriched values starting at 10.5k cal abpat this site that is not present in most other records. The last deglaciation changes may be due to variations in local temperature, sea ice cover in the Barents and Kara seas, and plant community shifts impacting transpiration. The enrichment starting at 10.5‐k cal abpprobably records a shift towards modern climate conditions, caused by the loss of the Scandinavian Ice Sheet, increased locally sourced moisture from the Barents and Kara seas, and northward treeline migration causing enhanced transpiration. Future warming may increase summer precipitation in this region, with changes to local ecosystems and carbon cycling.
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- PAR ID:
- 10307166
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Quaternary Science
- Volume:
- 37
- Issue:
- 5
- ISSN:
- 0267-8179
- Page Range / eLocation ID:
- p. 790-804
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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