scholarly journals Palaeobiological evidence for Southern Hemisphere Younger Dryas and volcanogenic cold periods

2021 ◽  
Author(s):  
Richard N. Holdaway
Keyword(s):  
New Zealand ◽  
Southern Hemisphere ◽  
Younger Dryas ◽  
Volcanic Eruptions ◽  
Isotopic Data ◽  
Habitat Specialist ◽  
Radiocarbon Age ◽  
The Antarctic ◽  
Age Series ◽  
Glacial Climate

Abstract. Current consensus places a Southern Hemisphere post-glacial cooling episode earlier than the Younger Dryas in the Northern Hemisphere. New Zealand sequences of glacial moraines and speleothem isotopic data are generally interpreted as supporting the absence of a Southern Hemisphere Younger Dryas. Radiocarbon age series of habitat specialist moa (Aves: Dinornithiformes) show, however, that a sudden return to glacial climate in central New Zealand contemporary with the Younger Dryas. The cooling followed significant warming, not cooling, during the period of the Antarctic Cold Reversal. In addition, the moa sequence chronology also shows that the Oruanui (New Zealand) and Mt Takahe (Antarctica) volcanic eruptions were contemporary with abrupt cooling events in New Zealand. The independent high spatial and temporal resolution climate chronology reported here is contrary to an inter-hemispheric post-glacial climate see-saw model.

Timing of the late-glacial climate reversal in the Southern Hemisphere using high-resolution radiocarbon chronology for Kaipo Bog, New Zealand

2006 ◽  
Vol 65 (02) ◽  
pp. 340-345 ◽  
Author(s):  
Irka Hajdas ◽  
David J. Lowe ◽  
Rewi M. Newnham ◽  
Georges Bonani
Keyword(s):  
Climate Change ◽  
New Zealand ◽  
High Resolution ◽  
Southern Hemisphere ◽  
Younger Dryas ◽  
Late Glacial ◽  
Bulk Sediment ◽  
Radiocarbon Chronology ◽  
The Antarctic ◽  
Glacial Climate

AbstractThe pattern of climate change in the Southern Hemisphere during the Younger Dryas (YD) chronozone provides essential constraint on mechanisms of abrupt climate change only if accurate, high-precision chronologies are obtained. A climate reversal reported previously at Kaipo bog, New Zealand, had been dated between 13,600 and 12,600 cal yr B.P. and appeared to asynchronously overlap the YD chron, but the chronology, based on conventionally radiocarbon-dated bulk sediment samples, left the precise timing questionable. We report a new high-resolution AMS 14C chronology for the Kaipo record that confirms the original chronology and provides further evidence for a mid-latitude Southern Ocean cooling event dated between 13,800 and 12,400 cal yr B.P. (2σ range), roughly equivalent to the Antarctic Cold Reversal.

scholarly journals A high-altitude snow chemistry record from Amundsenisen, Dronning Maud Land, Antarctica

2001 ◽  
Vol 47 (158) ◽  
pp. 489-496 ◽  
Author(s):  
Elisabeth Isaksson ◽  
Wibjörn Karlén ◽  
Paul Mayewski ◽  
Mark Twickler ◽  
Sallie Whitlow
Keyword(s):  
New Zealand ◽  
High Altitude ◽  
Major Ions ◽  
Southern Oscillation ◽  
Austral Summer ◽  
Volcanic Eruptions ◽  
The Core ◽  
Dronning Maud Land ◽  
South Shetlands ◽  
The Antarctic

AbstractIn this paper a detailed record of major ions from a 20 m deep firn core from Amundsenisen, western Dronning Maud Land, Antarctica, is presented. The core was drilled at 75° S, 2° E (2900 m a.s.l.) during austral summer 1991/92. The following ions were measured at 3 cm resolution: Na+, Mg2+, Ca2+, Cl−, NO3−, S042− and CH3SO3H (MSA). The core was dated back to 1865 using a combination of chemical records and volcanic reference horizons. The volcanic eruptions identified in this core are Mount Ngauruhoe, New Zealand (1974–75), Mount Agung, Indonesia (1963), Azul, Argentina (1932), and a broad peak that corresponds in time toTarawera, New Zealand (1886), Falcon Island, South Shetlands, Southern Ocean (1885), and Krakatau, Indonesia (1883). There are no trends in any of the ion records, but the annual to decadal changes are large. The mean concentrations of the measured ions are in agreement with those from other high-altitude cores from the Antarctic plateau. At this core site there may be a correspondence between peaks in the MSA record and major El Niño–Southern Oscillation events.

scholarly journals A beryllium-10 chronology of late-glacial moraines in the upper Rakaia valley, Southern Alps, New Zealand supports Southern-Hemisphere warming during the Younger Dryas

2017 ◽  
Vol 170 ◽  
pp. 14-25 ◽  
Author(s):  
Tobias N.B. Koffman ◽  
Joerg M. Schaefer ◽  
Aaron E. Putnam ◽  
George H. Denton ◽  
David J.A. Barrell ◽  
...  
Keyword(s):  
New Zealand ◽  
Southern Hemisphere ◽  
Younger Dryas ◽  
Late Glacial ◽  
Southern Alps

scholarly journals A palaeoenvironmental record of the Southern Hemisphere last glacial maximum from the Mount Cass loess section, North Canterbury, Aotearoa/New Zealand

2020 ◽  
pp. 1-15
Author(s):  
Peter C. Almond ◽  
Sándor Gulyás ◽  
Pál Sümegi ◽  
Balázs P. Sümegi ◽  
Stephen Covey-Crump ◽  
...  
Keyword(s):  
New Zealand ◽  
Southern Hemisphere ◽  
Last Glacial Maximum ◽  
Climatic Variability ◽  
Glacial Maximum ◽  
Pollen Record ◽  
Good Correspondence ◽  
Last Glacial ◽  
Event Stratigraphy ◽  
Westerly Winds

Abstract Calcareous loess in North Canterbury, eastern South Island, New Zealand (NZ), preserves subfossil bird bone, terrestrial gastropods, and eggshell, whose abundances and radiocarbon ages allowed us to reconstruct aspects of palaeoenvironment at high resolution through 25 to 21 cal ka BP. This interval includes millennial-scale climatic variability during the extended last glacial maximum (30–18 ka) of Australasia. Our loess palaeoclimatic record shows good correspondence with stadial and interstadial climate events of the NZ Climate Event Stratigraphy, which were defined from a pollen record on the western side of South Island. An interstade from 25.4 to 24 cal ka BP was warm but also relatively humid on eastern South Island, and loess grain size may indicate reduced vigour of the Southern Hemisphere westerly winds. The subsequent stade (24–22.6 cal ka BP) was drier, colder, and probably windier. The next interstade remained relatively dry on eastern South Island, and westerly winds remained vigorous. The 25.4–24 ka interstade is synchronous with Heinrich stade 2, which may have driven a southward migration of the subtropical front, leading to warming and wetting of northern and central South Island and retreat of Southern Alps glaciers at ca. 26.5 ka.

The search for an alternative strategy: New Zealand and the Antarctic

1983 ◽  
Vol 72 (288) ◽  
pp. 466-472 ◽  
Author(s):  
Laurie Barber ◽  
Michael Selby
Keyword(s):  
New Zealand ◽  
Alternative Strategy ◽  
The Antarctic

Chemical Composition of Ice Containing Tephra Layers in the Byrd Station Ice Core, Antarctica

1988 ◽  
Vol 30 (3) ◽  
pp. 315-330 ◽  
Author(s):  
Julie M. Palais ◽  
Philip R. Kyle
Keyword(s):  
Chemical Composition ◽  
Silicate Glass ◽  
Residence Time ◽  
Volcanic Ash ◽  
Global Climate ◽  
Ice Core ◽  
Volcanic Eruptions ◽  
Tephra Layers ◽  
The Antarctic ◽  
Hydrolysis Of

The chemical composition of ice containing tephra (volcanic ash) layers in 22 sections of the Byrd Station ice core was examined to determine if the volcanic eruptions affected the chemical composition of the atmosphere and precipitation in the vicinity of Byrd Station. The liquid conductivity, acidity, sulfate, nitrate, aluminum, and sodium concentrations of ice samples deposited before, during, and after the deposition of the tephra layers were analyzed. Ice samples that contain tephra layers have, on average, about two times more sulfate and three to four times more aluminum than nonvolcanic ice samples. The acidity of ice samples associated with tephra layers is lowered by hydrolysis of silicate glass and minerals. Average nitrate, sodium, and conductivity are the same in all samples. Because much of the sulfur and chlorine originally associated with these eruptions may have been scavenged by ash particles, the atmospheric residence time of these volatiles would have been minimized. Therefore the eruptions probably had only a small effect on the composition of the Antarctic atmosphere and a negligible effect on local or global climate.

Long-term Aptian marine osmium isotopic record of Ontong Java Nui activity

Geology ◽  
2021 ◽  
Author(s):  
Hironao Matsumoto ◽  
Rodolfo Coccioni ◽  
Fabrizio Frontalini ◽  
Kotaro Shirai ◽  
Luigi Jovane ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Volcanic Eruptions ◽  
Hydrothermal Activity ◽  
Published Data ◽  
Isotopic Data ◽  
Oceanic Plateaus ◽  
Carbon Burial ◽  
Organic Carbon Burial ◽  
Isotopic Records

The early to mid-Aptian was punctuated by episodic phases of organic-carbon burial in various oceanographic settings, which are possibly related to massive volcanism associated with the emplacement of the Ontong Java, Manihiki, and Hikurangi oceanic plateaus in the southwestern Pacific Ocean, inferred to have formed a single plateau called Ontong Java Nui. Sedimentary osmium (Os) isotopic compositions are one of the best proxies for determining the timing of voluminous submarine volcanic episodes. However, available Os isotopic records during the age are limited to a narrow interval in the earliest Aptian, which is insufficient for the reconstruction of long-term hydrothermal activity. We document the early to mid-Aptian Os isotopic record using pelagic Tethyan sediments deposited in the Poggio le Guaine (Umbria-Marche Basin, Italy) to precisely constrain the timing of massive volcanic episodes and to assess their impact on the marine environment. Our new Os isotopic data reveal three shifts to unradiogenic values, two of which correspond to black shale horizons in the lower to mid-Aptian, namely the Wezel (herein named) and Fallot Levels. These Os isotopic excursions are ascribed to massive inputs of unradiogenic Os to the ocean through hydrothermal activity. Combining the new Os isotopic record with published data from the lowermost Aptian organic-rich interval in the Gorgo a Cerbara section of the Umbria-Marche Basin, it can be inferred that Ontong Java Nui volcanic eruptions persisted for ~5 m.y. during the early to mid-Aptian.

Mawson’s views on use of natural resources in the Antarctic and sub-Antarctic

Polar Record ◽  
2021 ◽  
Vol 57 ◽  
Author(s):  
Peter D. Shaughnessy ◽  
Mark Pharaoh
Keyword(s):  
New Zealand ◽  
Natural Resources ◽  
Historical Context ◽  
Wildlife Sanctuary ◽  
Elephant Seals ◽  
Macquarie Island ◽  
Antarctic Expedition ◽  
Southern Elephant Seals ◽  
Meteorological Observations ◽  
The Antarctic

Abstract Sir Douglas Mawson is a well-known Antarctic explorer and scientist. Early in his career, he recognised opportunities for commerce in Antarctic and sub-Antarctic regions. While at Cape Denison, Antarctica, in 1913 on the Australasian Antarctic Expedition (AAE), the Adelie Blizzard magazine was produced. Mawson contributed articles about Antarctic natural resources and their possible use. Later, he advocated Australia be involved in pelagic whaling. He collected seal skins and oil for their commercial value to be assessed by the Hudson’s Bay Company. During the AAE, Mawson visited Macquarie Island where an oiling gang was killing southern elephant seals and royal penguins. Mawson was concerned that they were over-exploited and lobbied successfully to stop the killing. His plans for Macquarie Island included a wildlife sanctuary, with a party to supervise access, send meteorological observations to Australia and New Zealand, and be self-funded by harvesting elephant seals and penguins. Macquarie Island was declared a sanctuary in 1933. Although Mawson has been recognised as an early proponent of conservation, his views on conservation of living natural resources were inconsistent. They should be placed in their historical context: in the early twentieth century, utilisation of living natural resources was viewed more favourably than currently.

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