Southern high-latitude terrestrial climate change during the Palaeocene–Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau)
Contreras, L.; Pross, J.; Bijl, P.K.; O'Hara, R.B.; Raine, J.I.; Sluijs, A.; Brinkhuis, H. (2014). Southern high-latitude terrestrial climate change during the Palaeocene–Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau). Clim. Past 10: 1401-1420. http://dx.doi.org/10.5194/cp-10-1401-2014
In: Climate of the Past. Copernicus: Göttingen. ISSN 1814-9324; e-ISSN 1814-9332, meer
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Auteurs | | Top |
- Contreras, L.
- Pross, J.
- Bijl, P.K.
- O'Hara, R.B.
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- Raine, J.I.
- Sluijs, A.
- Brinkhuis, H., meer
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Abstract |
Reconstructing the early Palaeogene climate dynamicsof terrestrial settings in the high southern latitudes isimportant to assess the role of high-latitude physical and biogeochemicalprocesses in the global climate system. However,whereas a number of high-quality Palaeogene climaterecords has become available for the marine realm of thehigh southern latitudes over the recent past, the long-termevolution of coeval terrestrial climates and ecosystems isyet poorly known. We here explore the climate and vegetationdynamics on Tasmania from the middle Palaeoceneto the early Eocene (60.7–54.2 Ma) based on a sporomorphrecord from Ocean Drilling Program (ODP) Site 1172 onthe East Tasman Plateau. Our results show that three distinctlydifferent vegetation types thrived on Tasmania undera high-precipitation regime during the middle Palaeoceneto early Eocene, with each type representing different temperatureconditions: (i) warm-temperate forests dominatedby gymnosperms that were dominant during the middleand late Palaeocene (excluding the middle/late Palaeocenetransition); (ii) cool-temperate forests dominated by southernbeech (Nothofagus) and araucarians that transiently prevailedacross the middle/late Palaeocene transition interval(?59.5 to ?59.0 Ma); and (iii) paratropical forests rich inferns that were established during and in the wake of thePalaeocene–Eocene Thermal Maximum (PETM). The transientestablishment of cool-temperate forests lacking anyfrost-sensitive elements (i.e. palms and cycads) across themiddle/late Palaeocene transition interval indicates markedlycooler conditions, with the occurrence of frosts in winter,on Tasmania during that time. The integration of our sporomorphdata with previously published TEX86-based seasurfacetemperatures from ODP Site 1172 documents thatthe vegetation dynamics on Tasmania were closely linkedwith the temperature evolution in the Tasman sector of theSouthwest Pacific region. Moreover, the comparison of ourseason-specific climate estimates for the sporomorph assemblagesfrom ODP Site 1172 with the TEXL86- and TEXH86-based temperature data suggests a warm bias of both calibrationsfor the early Palaeogene of the high southern latitudes. |
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