Late Quaternary deglaciation and climate history of the Larsemann Hills(East Antarctica)

AbstractMoraines southwest of Lake Yashilkul, Pamir, Tajikistan, were dated using 10Be exposure ages of boulder surfaces. We found evidence for (1) an extensive glaciation ∼60,000 yr ago; (2) a less extensive glacial advance, which deposited a characteristic hummocky moraine lobe with exposure ages ranging from ∼11,000 to 47,000 yr, probably deposited at or before 47,000 yr ago; and (3) lateral moraines with exposure ages of ∼40,000 yr, 27,000 yr and 19,000 yr, respectively. Increasing aridity in the Pamir is most likely responsible for the progressively limited extent of the glaciers during the Late Pleistocene.

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Late Quaternary vegetation and climate history of a perennial river canyon in the Río Salado basin (22°S) of Northern Chile

Quaternary Research ◽

10.1016/j.yqres.2006.02.002 ◽

2006 ◽

Vol 65 (3) ◽

pp. 450-466 ◽

Cited By ~ 94

Author(s):

Claudio Latorre ◽

Julio L. Betancourt ◽

Mary T.K. Arroyo

Keyword(s):

Late Quaternary ◽

Plant Macrofossils ◽

Annual Rainfall ◽

Mean Annual Temperature ◽

Northern Chile ◽

Climate History ◽

Emerging Trends ◽

History Of ◽

Bolivian Altiplano ◽

Vegetation And Climate

AbstractPlant macrofossils from 33 rodent middens sampled at three sites between 2910 and 3150 m elevation in the main canyon of the Río Salado, northern Chile, yield a unique record of vegetation and climate over the past 22,000 cal yr BP. Presence of low-elevation Prepuna taxa throughout the record suggests that mean annual temperature never cooled by more than 5°C and may have been near-modern at 16,270 cal yr BP. Displacements in the lower limits of Andean steppe and Puna taxa indicate that mean annual rainfall was twice modern at 17,520–16,270 cal yr BP. This pluvial event coincides with infilling of paleolake Tauca on the Bolivian Altiplano, increased ENSO activity inferred from a marine core near Lima, abrupt deglaciation in southern Chile, and Heinrich Event 1. Moderate to large increases in precipitation also occurred at 11,770–9550 (Central Atacama Pluvial Event), 7330–6720, 3490–2320 and at 800 cal yr BP. Desiccation occurred at 14,180, 8910–8640, and 4865 cal yr BP. Compared to other midden sites in the region, early Holocene desiccation seems to have happened progressively earlier farther south. Emerging trends from the cumulative midden record in the central Atacama agree at millennial timescales with improved paleolake chronologies for the Bolivian Altiplano, implying common forcing through changes in equatorial Pacific sea-surface temperature gradients.

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The Late Quaternary peat, vegetation and climate history of the Southern Oceanic Islands of New Zealand

Quaternary Science Reviews ◽

10.1016/s0277-3791(01)00044-0 ◽

2002 ◽

Vol 21 (4-6) ◽

pp. 683-707 ◽

Cited By ~ 47

Author(s):

M.S. McGlone

Keyword(s):

New Zealand ◽

Late Quaternary ◽

Oceanic Islands ◽

Climate History ◽

History Of ◽

Vegetation And Climate

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Late Quaternary climate-driven environmental change in the Larsemann Hills, East Antarctica, multi-proxy evidence from a lake sediment core

Quaternary Research ◽

10.1016/j.yqres.2005.04.002 ◽

2005 ◽

Vol 64 (1) ◽

pp. 83-99 ◽

Cited By ~ 69

Author(s):

Dominic A. Hodgson ◽

Elie Verleyen ◽

Koen Sabbe ◽

Angela H. Squier ◽

Brendan J. Keely ◽

...

Keyword(s):

Environmental Changes ◽

Accumulation Rate ◽

Late Quaternary ◽

East Antarctica ◽

Algal Community ◽

Data Set ◽

Last Glacial ◽

Larsemann Hills ◽

Quaternary Climate ◽

The Last Glacial

AbstractLittle is known about the response of terrestrial East Antarctica to climate changes during the last glacialâ€“interglacial cycle. Here we present a continuous sediment record from a lake in the Larsemann Hills, situated on a peninsula believed to have been ice-free for at least 40,000 yr. A mutli-proxy data set including geochronology, diatoms, pigments and carbonate stable isotopes indicates warmer and wetter conditions than present in the early part of the record. We interpret this as Marine Isotope Stage 5e after application of a chronological age-depth model and similar ice core evidence. Dry and cold conditions are inferred during the last glacial, with lake-level minima, floristic changes towards a shallow water algal community, and a greater biological receipt of ultraviolet radiation. During the Last Glacial Maximum and Termination I the lake was perennially ice-covered, with minimal snowmelt in the catchment. After ca. 10,500 cal yr B.P., the lake became seasonally moated or ice-free during summer. Despite a low accumulation rate, the sediments document some Holocene environmental changes including neoglacial cooling after ca. 2450 cal yr B.P., and a gradual increase in aridity and salinity to the present.

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Late Quaternary vegetation and climate history of the central Bering land bridge from St. Michael Island, western Alaska

Quaternary Research ◽

10.1016/s0033-5894(03)00068-1 ◽

2003 ◽

Vol 60 (1) ◽

pp. 19-32 ◽

Cited By ~ 66

Author(s):

Thomas A. Ager

Keyword(s):

Boreal Forests ◽

Vegetation Change ◽

Late Quaternary ◽

Land Bridge ◽

Climate History ◽

Middle Holocene ◽

Bering Land Bridge ◽

Dwarf Birch ◽

History Of ◽

Vegetation And Climate

AbstractPollen analysis of a sediment core from Zagoskin Lake on St. Michael Island, northeast Bering Sea, provides a history of vegetation and climate for the central Bering land bridge and adjacent western Alaska for the past ≥30,000 14C yr B.P. During the late middle Wisconsin interstadial (≥30,000–26,000 14C yr B.P.) vegetation was dominated by graminoid-herb tundra with willows (Salix) and minor dwarf birch (Betula nana) and Ericales. During the late Wisconsin glacial interval (26,000–15,000 14C yr B.P.) vegetation was graminoid-herb tundra with willows, but with fewer dwarf birch and Ericales, and more herb types associated with dry habitats and disturbed soils. Grasses (Poaceae) dominated during the peak of this glacial interval. Graminoid-herb tundra suggests that central Beringia had a cold, arid climate from ≥30,000 to 15,000 14C yr B.P. Between 15,000 and 13,000 14C yr B.P., birch shrub-Ericales-sedge-moss tundra began to spread rapidly across the land bridge and Alaska. This major vegetation change suggests moister, warmer summer climates and deeper winter snows. A brief invasion of Populus (poplar, aspen) occurred ca.11,000–9500 14C yr B.P., overlapping with the Younger Dryas interval of dry, cooler(?) climate. During the latest Wisconsin to middle Holocene the Bering land bridge was flooded by rising seas. Alder shrubs (Alnus crispa) colonized the St. Michael Island area ca. 8000 14C yr B.P. Boreal forests dominated by spruce (Picea) spread from interior Alaska into the eastern Norton Sound area in middle Holocene time, but have not spread as far west as St. Michael Island.

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