Late-Holocene Penguin Occupation and Diet at King George Island Antarctic Peninsula

2013 ◽  
pp. 171-180 ◽  
Author(s):  
Steven D. Emslie ◽  
Peter Ritchie ◽  
David Lambert
Keyword(s):  
Antarctic Peninsula ◽  
Late Holocene ◽  
King George Island

Phytoplankton in the embayments of King George Island (Antarctic Peninsula): a review with emphasis on diatoms

Polar Record ◽  
2018 ◽  
Vol 54 (2) ◽  
pp. 158-175 ◽  
Author(s):  
Priscila Kienteca Lange ◽  
Ryszard Ligowski ◽  
Denise Rivera Tenenbaum
Keyword(s):  
Antarctic Peninsula ◽  
Early Summer ◽  
Western Antarctic Peninsula ◽  
King George Island ◽  
Accurate Identification ◽  
Phytoplankton Assemblages ◽  
Marine Food Web ◽  
Planktonic Diatoms ◽  
Local Material ◽  
Marine Food

ABSTRACTConsidering that phytoplankton assemblages are good bioindicators of environmental conditions, the sensitivity of the Western Antarctic Peninsula (WAP) to climate change, and the importance of some areas of its islands as Antarctic Specially Managed Areas, this work assembles published datasets on phytoplankton biodiversity and ecology in confined coastal areas (embayments) of King George Island, WAP. Over 33 years (1980–2013), 415 species from 122 genera have been identified to species level, being mostly diatoms (371 species), with 10 new species described with local material (6 diatoms, 4 cyanobacteria). The importance of diatoms was indicated by the frequent occurrence of Corethron pennatum, Pseudogomphonema kamtshaticum, and abundant benthic genera in the plankton (e.g. Navicula, Cocconeis). The increased contribution of dinoflagellates after 2010 suggests marked changes in the water column. Early-summer blooms differ between the bays' eastern and western shores, with terrestrial melting and wind-driven upwelling inducing the dominance of benthic species at eastern shores, whereas planktonic diatoms (Thalassiosira, Pseudo-nizschia, and Chaetoceros) are most abundant along western shores and central areas. The importance of an accurate identification of organisms that are becoming key ecological components of the region is discussed, as recent changes in the microflora may affect the entire marine food web.

scholarly journals Mesospheric front observations by the OH airglow imager carried out at Ferraz Station on King George Island, Antarctic Peninsula, in 2011

2018 ◽  
Vol 36 (1) ◽  
pp. 253-264 ◽  
Author(s):  
Gabriel Augusto Giongo ◽  
José Valentin Bageston ◽  
Paulo Prado Batista ◽  
Cristiano Max Wrasse ◽  
Gabriela Dornelles Bittencourt ◽  
...  
Keyword(s):  
Antarctic Peninsula ◽  
Near Infrared ◽  
Middle Atmosphere ◽  
Convective Cloud ◽  
Atmospheric Composition ◽  
Secondary Wave ◽  
King George Island ◽  
Composition And Structure ◽  
Waves And Tides ◽  
Energy And Momentum

Abstract. The main goals of this work are to characterize and investigate the potential wave sources of four mesospheric fronts identified in the hydroxyl near-infrared (OH-NIR) airglow images, obtained with an all-sky airglow imager installed at Comandante Ferraz Antarctic Station (EACF, as per its Portuguese acronym) located on King George Island in the Antarctic Peninsula. We identified and analyzed four mesospheric fronts in 2011 over King George Island. In addition, we investigate the atmospheric background environment between 80 and 100 km altitude and discuss the ducts and propagation conditions for these waves. For that, we used wind data obtained from a meteor radar operated at EACF and temperature data obtained from the TIMED/SABER satellite. The vertical wavenumber squared, m2, was calculated for each of the four waves. Even though no clearly defined duct (indicated by positive values of m2 sandwiched between layers above and below with m2  < 0) was found in any of the events, favorable propagation conditions for horizontal propagation of the fronts were found in three cases. In the fourth case, the wave front did not find any duct support and it appeared to dissipate near the zenith, transferring energy and momentum to the medium and, consequently, accelerating the wind in the wave propagation direction (near to south) above the OH peak (88–92 km). The likely wave sources for these four cases were investigated by using meteorological satellite images and in two cases we could find that strong instabilities were potential sources, i.e., a cyclonic activity and a large convective cloud cell. In the other two cases it was not possible to associate troposphere sources as potential candidates for the generation of such wave fronts observed in the mesosphere and secondary wave sources were attributed to these cases. Keywords. Atmospheric composition and structure (airglow and aurora) – meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)

Influence of Climate Variability in King George Island Glacier Retreat – Antarctic Peninsula

2021 ◽  
Author(s):  
Ibeth Celia Rojas Macedo ◽  
Wilson Alfredo Suarez Alayza ◽  
Edwin Anibal Loarte Cadenas ◽  
Katy Damacia Medina Marcos
Keyword(s):  
Climate Variability ◽  
Antarctic Peninsula ◽  
Enso Event ◽  
Glacier Retreat ◽  
Glacier Mass Balance ◽  
Climatic Data ◽  
King George Island ◽  
Cooling Period ◽  
Glacier Shrinkage ◽  
Landsat Satellite

&lt;p&gt;This research aims to explain the influence of climatic variables (temperature and precipitation) in King George Island (KGI) glacier shrinkage on the Antarctic Peninsula. It employed Landsat satellite images from 1989 to 2020, climatic data and ONI index from 1980 to 2019.&lt;/p&gt;&lt;p&gt;King George Island glaciers have lost 10% of their coverage in the last 31 years. Greater glacier shrinkage was shown until the first mid-period assessed, while the retreat rate slowed down for the second half of the studied period. Furthermore, of 73 KGI glaciers, 37% were marine- and land-terminating, 42% were land-terminating and 21% were sea-terminating. Nonetheless, the decreases in the ice-coverage of marine-contact glaciers (35% of glacier coverage reduced) were higher than land-terminating glaciers (17% of glacier coverage reduced).&lt;/p&gt;&lt;p&gt;There was a perceivable fluctuation in annual average air temperature for the 1980-2006 period. Nevertheless, from around 2007 to 2015/2016 there was a slight continuous cooling period and precipitation was somewhat above the average. Therefore, these patterns could explain the recent KGI glacier-retreat deceleration.&lt;/p&gt;&lt;p&gt;Unlike the 1982/1983 and 1997/1998 El Ni&amp;#241;o events, the 2015/2016 El Ni&amp;#241;o was colder with precipitation reduction from the sustained annual amount (since roughly 2007 to 2015/2016) to values below the average. Moreover, during the 2015/2016 El Ni&amp;#241;o, KGI glacier coverage reduction was the lowest for the 31 year-long evaluated. However, it was revealed that the glacier's height could increase by accumulation in El Ni&amp;#241;o years, but glacier mass balance could be more negative due to basal melting. Additionally, land-terminating glaciers have lost more glacier coverage than sea-terminating glaciers throughout this ENSO event.&lt;/p&gt;&lt;p&gt;Hence, climate variability might play a significant role in KGI glacier shrinkage, but calving process, glacier features and so on, further a combination of them should be assessed to reach a better understanding of KGI glacier retreat.&lt;/p&gt;

Debris recorded in ice free areas of an Antarctic Specially Managed Area (ASMA): Admiralty Bay, King George Island, Antarctic Peninsula

2009 ◽  
Vol 4 (1) ◽  
pp. 36-39 ◽  
Author(s):  
Martin Sander ◽  
Erli Costa ◽  
Tatiana Balbão ◽  
Ana Paula Carneiro ◽  
César Santos
Keyword(s):  
Antarctic Peninsula ◽  
King George Island ◽  
Admiralty Bay

scholarly journals Late-Holocene changes in character and behaviour of land-terminating glaciers on James Ross Island, Antarctica

2012 ◽  
Vol 58 (212) ◽  
pp. 1176-1190 ◽  
Author(s):  
Jonathan L. Carrivick ◽  
Bethan J. Davies ◽  
Neil F. Glasser ◽  
Daniel Nývlt ◽  
Michael J. Hambrey
Keyword(s):  
Climate Change ◽  
Sediment Transport ◽  
Surface Structure ◽  
Antarctic Peninsula ◽  
Thermal Regime ◽  
Late Holocene ◽  
Negative Mass ◽  
Warming Climate ◽  
James Ross Island ◽  
Geometric Changes

AbstractVirtually no information is available on the response of land-terminating Antarctic Peninsula glaciers to climate change on a centennial timescale. This paper analyses the topography, geomorphology and sedimentology of prominent moraines on James Ross Island, Antarctica, to determine geometric changes and to interpret glacier behaviour. The moraines are very likely due to a late-Holocene phase of advance and featured (1) shearing and thrusting within the snout, (2) shearing and deformation of basal sediment, (3) more supraglacial debris than at present and (4) short distances of sediment transport. Retreat of ~100 m and thinning of 15–20 m has produced a loss of 0.1 km3 of ice. The pattern of surface lowering is asymmetric. These geometrical changes are suggested most simply to be due to a net negative mass balance caused by a drier climate. Comparisons of the moraines with the current glaciological surface structure of the glaciers permits speculation of a transition from a polythermal to a cold-based thermal regime. Small land-terminating glaciers in the northern Antarctic Peninsula region could be cooling despite a warming climate.

scholarly journals Kelp gulls, Larus dominicanus (Aves: Laridae), breeding in Keller Peninsula, King George Island, Antarctic Peninsula

2009 ◽  
Vol 26 (3) ◽  
pp. 562-566 ◽  
Author(s):  
Joaquim O. Branco ◽  
Erli S. Costa ◽  
Jansen de Araujo ◽  
Edison Durigon ◽  
Maria Alice S. Alves
Keyword(s):  
Antarctic Peninsula ◽  
King George Island ◽  
Larus Dominicanus

Unstable Climate Oscillations during the Late Holocene in the Eastern Bransfield Basin, Antarctic Peninsula

2002 ◽  
Vol 58 (3) ◽  
pp. 234-245 ◽  
Author(s):  
Boo-Keun Khim ◽  
Ho Il Yoon ◽  
Cheon Yun Kang ◽  
Jang Jun Bahk
Keyword(s):  
Antarctic Peninsula ◽  
Late Holocene ◽  
Accumulation Rate ◽  
Silica Content ◽  
Climatic Conditions ◽  
Ice Age ◽  
Geochemical Data ◽  
Sediment Properties ◽  
Bransfield Basin ◽  
Distinct Features

AbstractCore A9-EB2 from the eastern Bransfield Basin, Antarctic Peninsula, consists of pelagic (diatom ooze-clay couplets and bioturbated diatom ooze) and hemipelagic (bioturbated mud) sediments interbedded with turbidites (homogeneous mud and silt–clay couplets). The cyclic and laminated nature of these pelagic sediments represents alternation between the deposition of diatom-rich biogenic sediments and of terrigenous sediments. Sediment properties and geochemical data explain the contrasting lamination, with light layers being finer-grained and relatively rich in total organic carbon and biogenic silica content. Also, the high-resolution magnetic susceptibility (MS) variations highlight distinct features: high MS values coincide with clastic-rich sections and low MS values correspond to biogenic sections. The chronology developed for core A9-EB2 accounts for anomalous ages associated with turbidites and shows a linear sedimentation rate of approximately 87 cm/103 yr, which is supported by an accumulation rate of 80 cm/103 yr calculated from 210Pb activity. The late Holocene records clearly identify Neoglacial events of the Little Ice Age (LIA) and Medieval Warm Period (MWP). Other unexplained climatic events comparable in duration and amplitude to the LIA and MWP events also appear in the MS record, suggesting intrinsically unstable climatic conditions during the late Holocene in the Bransfield Basin of Antarctic Peninsula.

scholarly journals Variations in ice rafted detritus on beaches in the South Shetland Islands: a possible climate proxy

2004 ◽  
Vol 16 (3) ◽  
pp. 339-344 ◽  
Author(s):  
BRENDA L. HALL ◽  
ETHAN R. PERRY
Keyword(s):  
Antarctic Peninsula ◽  
Ocean Circulation ◽  
Late Holocene ◽  
Warming Trend ◽  
South Shetland Islands ◽  
The South ◽  
Shetland Islands ◽  
Livingston Island ◽  
The Antarctic ◽  
Glacial Advance

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 modern beach exhibits little IRD, all of which is of local origin, the next highest beach (∼250 14C yr BP) has large amounts, some of which comes from as far away as the Antarctic Peninsula. Significant quantities of IRD also were deposited ∼1750 14C yr BP. Both time periods coincide with generally cooler regional conditions and, at least in the case of the ∼250 yr old beach, local glacial advance. We suggest that the increases in ice rafting may reflect periods of greater glacial activity, altered ocean circulation, and/or greater iceberg preservation during the late Holocene. Limited IRD and lack of far-travelled erratics on the modern beach are both consistent with the ongoing warming trend in the Antarctic Peninsula region.

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