Academic Journal
A review of Tertiary climate changes in southern South America and the Antarctic Peninsula. Part 2: continental conditions
| العنوان: | A review of Tertiary climate changes in southern South America and the Antarctic Peninsula. Part 2: continental conditions |
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| المؤلفون: | Le Roux, J. P. |
| بيانات النشر: | Elsevier |
| سنة النشر: | 2012 |
| المجموعة: | Universidad de Chile: Captura |
| مصطلحات موضوعية: | Climate change, Tertiary, South America, Antarctic Peninsula, Sea-floor spreading, Greenhouse gases, Andes Range |
| الوصف: | Artículo de publicación ISI ; Climate changes in southern South America and the Antarctic Peninsula during the Tertiary show a strong correlation with ocean warming and cooling events, which are in turn related to tectonic processes. During periods of accelerated sea-floor spreading and mid-ocean ridge activity, sea-levels rose so that parts of the continents were flooded and forests were destroyed. However, this was balanced by the large-scale release of CO2 during volcanic outgassing and carbonate precipitation on the continental shelves, which caused rising air temperatures and the poleward expansion of (sub)tropical and temperate forests. Cooling episodes generally caused an increase in the north–south thermal gradient because of an equatorward shift in climate belts, so that the Westerly Winds intensified and brought higher rainfall to the lower latitudes. An increase in wind-blown dust caused temperatures to drop further by reflecting sunlight back into space. The rising Andes Range had a marked influence on climate patterns. Up to the middle Miocene it was still low enough to allow summer rainfall to reach central and north-central Chile, but after about 14 Ma it rose rapidly and effectively blocked the spill-over of moisture from the Atlantic Ocean and Amazon Basin. At this time, the cold Humboldt Current was also established, which together with the Andes helped to create the “Arid Diagonal” of southern South America stretching from the Atacama Desert to the dry steppes of Patagonia. This caused the withdrawal of subtropical forests to south-central Chile and the expansion of sclerophytic vegetation to central Chile. However, at the same time it intercepted more rain from the northeast, causing the effect of the South American monsoon to intensify in northwestern Argentina and southern Bolivia, where forest communities presently occur. In Patagonia, glaciation started as early as 10.5 Ma, but by 7 Ma had become a prominent feature of the landscape and continued apparently uninterruptedly into the ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| Relation: | Sedimentary Geology 247–248 (2012) 21–38; http://www.captura.uchile.cl/handle/2250/16682 |
| DOI: | 10.1016/j.sedgeo.2011.12.001 |
| الاتاحة: | https://doi.org/10.1016/j.sedgeo.2011.12.001 http://www.captura.uchile.cl/handle/2250/16682 |
| رقم الانضمام: | edsbas.CBBBF2F |
| قاعدة البيانات: | BASE |
| DOI: | 10.1016/j.sedgeo.2011.12.001 |
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