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Antarctic Climate Change And The Environment, Peter Convey, R. Bindschadler, G. Di Prisco, E. Fahrbach, J. Gutt, D. A. Hodgson, Paul Andrew Mayewski, C. P. Summerhayes, J. Turner, Acce Consortium
Antarctic Climate Change And The Environment, Peter Convey, R. Bindschadler, G. Di Prisco, E. Fahrbach, J. Gutt, D. A. Hodgson, Paul Andrew Mayewski, C. P. Summerhayes, J. Turner, Acce Consortium
Earth Science Faculty Scholarship
The Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (similar to the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential …
Chevkinite-Group Minerals From Granulite-Facies Metamorphic Rocks And Associated Pegmatites Of East Antarctica And South India, H. E. Belkin, R. Macdonald, Edward S. Grew
Chevkinite-Group Minerals From Granulite-Facies Metamorphic Rocks And Associated Pegmatites Of East Antarctica And South India, H. E. Belkin, R. Macdonald, Edward S. Grew
Earth Science Faculty Scholarship
Electron microprobe data are presented for chevkinite-group minerals from granulite-facies rocks and associated pegmatities of the Napier Complex and Mawson Station charnockite in East Antarctica and from the Eastern Ghats, South India. Their compositions conform to the general formula for this group, viz. A(4)BC(2)D(2)Si(4)O(22) where, in the analysed specimens A = (rare-earth elements (REE), Ca, Y, Th), B = Fe(2+) Mg, C = (Al, Mg, Ti, Fe(2+), Fe(3+), Zr) and D = Ti and plot within the perrierite field oftlic total Fe (as FeO) (wt.%) vs. CaO (wt.%) discriminator diagram of Macdonald and Belkin (2002). In contrast to most chevkinite-group …
Variations In Ice Rafted Detritus On Beaches In The South Shetland Islands: A Possible Climate Proxy, Brenda L. Hall, Ethan R. Perry
Variations In Ice Rafted Detritus On Beaches In The South Shetland Islands: A Possible Climate Proxy, Brenda L. Hall, Ethan R. Perry
Earth Science Faculty Scholarship
Raised beach ridges on Livingston Island of the South Shetland Islands display variations in both quantity and source of ice rafted detritus (IRD) received over time. Whereas the modem beach exhibits little IRD, all of which is of local origin, the next highest beach (similar to250 C-14 yr BP) has large amounts, some of which comes from as far away as the Antarctic Peninsula. Significant quantities of IRD also were deposited similar to 1750 C-14 yr BP. Both time periods coincide with generally cooler regional conditions and, at least in the case of the similar to250 yr old beach, local …
Glacial Lake Wright, A High-Level Antarctic Lake During The Lgm And Early Holocene, Brenda L. Hall, George H. Denton, B. Overturf
Glacial Lake Wright, A High-Level Antarctic Lake During The Lgm And Early Holocene, Brenda L. Hall, George H. Denton, B. Overturf
Earth Science Faculty Scholarship
We report evidence of a large proglacial lake (Glacial Lake Wright) that existed in Wright Valley in the McMurdo Dry Valleys region of Antarctica at the last glacial maximum (LGM) and in the early Holocene. At its highstands, Glacial Lake Wright would have stretched 50 km and covered c. 210 km(2). Chronology for lake-level changes comes from 30 AMS radiocarbon dates of lacustrine algae preserved in deltas, shorelines, and glaciolacustrine deposits that extend up to 480 m above present-day lakes. Emerging evidence suggests that Glacial Lake Wright was only one of a series of large lakes to occupy the McMurdo …
Antarctic Glacial History Since The Last Glacial Maximum: An Overview Of The Record On Land, Ólafur Ingólfsson, Christian Hjort, Paul A. Berkman, Svante Björck, Eric Colhoun, Ian D. Goodwin, Brenda Hall, Kazuomi Hirakawa, Martin Melles, Per Möller, Michael L. Prentice
Antarctic Glacial History Since The Last Glacial Maximum: An Overview Of The Record On Land, Ólafur Ingólfsson, Christian Hjort, Paul A. Berkman, Svante Björck, Eric Colhoun, Ian D. Goodwin, Brenda Hall, Kazuomi Hirakawa, Martin Melles, Per Möller, Michael L. Prentice
Earth Science Faculty Scholarship
This overview examines available circum-Antarctic glacial history archives on land, related to developments after the Last Glacial Maximum (LGM). It considers the glacial-stratigraphic and morphologic records and also biostratigraphical information from moss banks, lake sediments and penguin rookeries, with some reference to relevant glacial marine records. It is concluded that Holocene environmental development in Antarctica differed from that in the Northern Hemisphere. The initial deglaciation of the shelf areas surrounding Antarctica took place before 10000 C-14 yrs before present(sp), and was controlled by rising global sea level. This was followed by the deglaciation of some presently ice-free inner shelf and …