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| 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 |
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| Calvo, Eva; Pelejero, Carles; De Deckker, Patrick; Logan, Graham A.. |
| Comparison of ice cores from Greenland and Antarctica shows an asynchronous two-step warming at these high latitudes during the Last Termination. However, the question whether this asynchrony extends to lower latitudes is unclear mainly due to the scarcity of paleorecords from the Southern Hemisphere. New data from a marine core collected off South Australia (similar to 36 degrees S) allows a detailed reconstruction of sea-surface temperatures over the Last Termination. This confirms the existence of an Antarctic-type deglacial pattern and shows no indication of cooling associated with the Northern Hemisphere YD event. The SST record also provides a new comparison with the more extensive paleoclimatic data available from continental Australia. This shows a... |
| Tipo: Text |
Palavras-chave: Alkenones; Deglaciation; Southern Hemisphere. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00235/34647/33013.pdf |
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| Lopes Dos Santos, Raquel A.; Spooner, Michelle I.; Barrows, Timothy T.; De Deckker, Patrick; Damste, Jaap S. Sinninghe; Schouten, Stefan. |
| Several proxies have been developed to reconstruct past sea surface temperature (SST), but different proxies may reflect temperatures of different seasons and each proxy is characterized by certain uncertainties. Therefore, a multiproxy approach is preferred to precisely reconstruct SST. Here, we reconstruct SST of the ocean offshore southeastern Australia (Murray Canyons area) for the last ~135 ka using three independent organic proxies (TEXH86 based on glycerol dialkyl glycerol tetraethers (GDGTs), UK'37 based on alkenones, and LDI based on long-chain diols) in addition to foraminiferal faunal assemblages. The organic proxy records show similar trends, with the highest temperature (21°C for UK'37 and TEXH86, and 25°C for LDI) during the last interglacial... |
| Tipo: Text |
Palavras-chave: Sea surface temperature; LDI index; TEX86H index; U-37(K') index; Foraminiferal assemblages; SE Australia. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00246/35763/34274.pdf |
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| Bayon, Germain; De Deckker, Patrick; Magee, John W.; Germain, Yoan; Bermell, Sylvain; Tachikawa, Kazuyo; Norman, Marc D.. |
| Millennial-scale cooling events termed Heinrich Stadials punctuated Northern Hemisphere climate during the last glacial period. Latitudinal shifts of the intertropical convergence zone (ITCZ) are thought to have rapidly propagated these abrupt climatic signals southward, influencing the evolution of Southern Hemisphere climates and contributing to major reorganisation of the global ocean-atmosphere system. Here, we use neodymium isotopes from a marine sediment core to reconstruct the hydroclimatic evolution of subtropical Australia between 90 to 20 thousand years ago. We find a strong correlation between our sediment provenance proxy data and records for western Pacific tropical precipitations and Australian palaeolakes, which indicates that Northern... |
| Tipo: Text |
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| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00375/48585/48906.pdf |
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| Barrows, Timothy T.; Juggins, Steve; De Deckker, Patrick; Calvo, Eva; Pelejero, Carles. |
| We compile and compare data for the last 150,000 years from four deep-sea cores in the midlatitude zone of the Southern Hemisphere. We recalculate sea surface temperature estimates derived from foraminifera and compare these with estimates derived from alkenones and magnesium/calcium ratios in foraminiferal carbonate and with accompanying sedimentological and pollen records on a common absolute timescale. Using a stack of the highest-resolution records, we find that first-order climate change occurs in concert with changes in insolation in the Northern Hemisphere. Glacier extent and inferred vegetation changes in Australia and New Zealand vary in tandem with sea surface temperatures, signifying close links between oceanic and terrestrial temperature. In... |
| Tipo: Text |
Palavras-chave: Sea surface temperature; Climate change; Australia–New Zealand. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00238/34941/33245.pdf |
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| Reeves, Jessica M.; Bostock, Helen C.; Ayliffe, Linda K.; Barrows, Timothy T.; De Deckker, Patrick; Devriendt, Laurent S.; Dunbar, Gavin B.; Drysdale, Russell N.; Fitzsimmons, Kathryn E.; Gagan, Michael K.; Griffiths, Michael L.; Haberle, Simon G.; Jansen, John D.; Krause, Claire; Lewis, Stephen; Mcgregor, Helen V.; Mooney, Scott D.; Moss, Patrick; Nanson, Gerald C.; Purcell, Anthony; Van Der Kaars, Sander. |
| The tropics are the major source of heat and moisture for the Australasian region. Determining the tropics' response over time to changes in climate forcing mechanisms, such as summer insolation, and the effects of relative sea level on exposed continental shelves during the Last Glacial period, is an ongoing process of re-evaluation. We present a synthesis of climate proxy data from tropical Australasia spanning the last 30,000 years that incorporates deep sea core, coral, speleothem, pollen, charcoal and terrestrial sedimentary records. Today, seasonal variability is governed largely by the annual migration of the inter-tropical convergence zone (ITCZ), influencing this region most strongly during the austral summer. However, the position of the ITCZ has... |
| Tipo: Text |
Palavras-chave: ITCZ; LGM; INTIMATE; Australasia; Indo-Pacific Warm Pool; Tropics; Australian monsoon. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00264/37502/36909.pdf |
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| Kuhnt, Wolfgang; Holbourn, Ann; Xu, Jian; Opdyke, Bradley; De Deckker, Patrick; Roehl, Ursula; Mudelsee, Manfred. |
| The evolution of the Australian monsoon in relation to high-latitude temperature fluctuations over the last termination remains highly enigmatic. Here we integrate high-resolution riverine runoff and dust proxy data from X-ray fluorescence scanner measurements in four well-dated sediment cores, forming a NE-SW transect across the Timor Sea. Our records reveal that the development of the Australian monsoon closely followed the deglacial warming history of Antarctica. A minimum in riverine runoff documents dry conditions throughout the region during the Antarctic Cold Reversal (15-12.9 ka). Massive intensification of the monsoon coincided with Southern Hemisphere warming and intensified greenhouse forcing over Australia during the atmospheric CO2 rise at... |
| Tipo: Text |
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| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00352/46296/45939.pdf |
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| Sadekov, Aleksey; Eggins, Stephen M.; De Deckker, Patrick; Ninnemann, Ulysses; Kuhnt, Wolfgang; Bassinot, Franck. |
| Laser-ablation inductively coupled plasma-mass spectrometry microanalyses of Mg/Ca across individual final chambers of three planktonic foraminifera species, Globigerinoides ruber, G. sacculifer, and Pulleniatina obliquiloculata, reveal significant interspecies differences in test Mg concentrations. Whereas these three species have similar Mg/Ca values at low sea surface temperatures (similar to 22 degrees C), they diverge markedly at high sea surface temperatures (similar to 29 degrees C). Explanations for these differences in species Mg/Ca values based on detailed comparison of species intratest Mg/Ca distributions suggest that compositional variability within tests cannot account for the observed deviation of species Mg/Ca values in warm-water... |
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| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00218/32934/31448.pdf |
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