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| Patterson, William P.; Dietrich, Kristin A.; Holmden, Chris; Andrews, John T.. |
| delta(18)O values of mollusks recovered from near-shore marine cores in northwest Iceland quantify significant variation in seasonal temperature over the period from similar to 360 B:C: to similar to A:D: 1660. Twenty-six aragonitic bivalve specimens were selected to represent intervals of climatic interest by using core sedimentological characteristics. Carbonate powder was sequentially micromilled from shell surfaces concordant with growth banding and analyzed for stable oxygen (delta(18)O) and carbon (delta(13)C) isotope values. Because delta(18)O values record subseasonal temperature variation over the lifetime of the bivalves, these data provide the first 2,000-year secular record of North Atlantic seasonality from ca. 360 cal yr B.C. to cal yr A.D.... |
| Tipo: Text |
Palavras-chave: Climate change; Stable isotopes; Vikings; Micromilling. |
| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00231/34231/32834.pdf |
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| Lachniet, Matthew S.; Johnson, Leah; Asmerom, Yemane; Burns, Stephen J.; Polyak, Victor; Patterson, William P.; Burt, Lindsay; Azouz, April. |
| We present a high-resolution terrestrial archive of Central American rainfall over the period 100-24 and 8.1-6.5 ka, based on delta(18)O time series from U-series dated stalagmites collected from a cave on the Pacific Coast of Costa Rica. Our results indicate substantial delta(18)O variability on millennial to orbital time scales that is interpreted to reflect rainfall variations over the cave site. Correlations with other paleoclimate proxy records suggest that the rainfall variations are forced by sea surface temperatures (SST) in the Atlantic and Pacific Oceans in a fashion analogous to the modern climate cycle. Higher rainfall is associated with periods of a warm tropical North Atlantic Ocean and large SST gradients between the Atlantic and Pacific... |
| Tipo: Text |
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| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00219/33020/31488.pdf |
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