|
|
|
|
|
Stuut, Jan‐berend W.; De Deckker, Patrick; Saavedra‐pellitero, Mariem; Bassinot, Franck; Drury, Anna‐joy; Walczak, Maureen H.; Nagashima, Kana; Murayama, Masafumi. |
New proxy records from deep‐sea sediment cores from the northwestern continental margin of Western Australian reveal a 5.3 million‐year (Ma) history of aridity and tropical‐monsoon activity in northwestern Australia. Following the warm and dry early Pliocene (~5.3 Ma), the northwestern Australian continent experienced a gradual increase in humidity peaking at about 3.8 Ma with higher than present‐day rainfall. Between 3.8 and about 2.8 Ma, climate became progressively more arid with more rainfall variability. Coinciding with the onset of the northern hemisphere glaciations and the intensification of the northern hemisphere monsoon, aridity continued to increase overall from 2.8 Ma until today, with greater variance in precipitation and an increased... |
Tipo: Text |
Palavras-chave: Paleoclimate; Monsoon; Australia; Runoff; Pliocene; Quaternary. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00502/61384/65035.pdf |
| |
|
|
Praetorius, Summer K.; Condron, Alan; Mix, Alan C.; Walczak, Maureen H.; Mckay, Jennifer L.; Du, Jianghui. |
Columbia River megafloods occurred repeatedly during the last deglaciation, but the impacts of this fresh water on Pacific hydrography are largely unknown. To reconstruct changes in ocean circulation during this period, we used a numerical model to simulate the flow trajectory of Columbia River megafloods and compiled records of sea surface temperature, paleo-salinity, and deep-water radiocarbon from marine sediment cores in the Northeast Pacific. The North Pacific sea surface cooled and freshened during the early deglacial (19.0-16.5 ka) and Younger Dryas (12.9-11.7 ka) intervals, coincident with the appearance of subsurface water masses depleted in radiocarbon relative to the sea surface. We infer that Pacific meltwater fluxes contributed to net Northern... |
Tipo: Text |
|
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00611/72288/71102.pdf |
| |
|
|
|