Perfluorinated compounds in the Antarctic region: Ocean circulation provides prolonged protection from distant sources

2010 ◽  
Vol 158 (9) ◽  
pp. 2985-2991 ◽  
Author(s):  
Susan Bengtson Nash ◽  
Stephen R. Rintoul ◽  
So Kawaguchi ◽  
Iain Staniland ◽  
John van den Hoff ◽  
...  
Keyword(s):  
Ocean Circulation ◽  
Perfluorinated Compounds ◽  
Antarctic Region ◽  
The Antarctic

The Role of Oscillating Southern Hemisphere Westerly Winds: Global Ocean Circulation

2020 ◽  
Vol 33 (6) ◽  
pp. 2111-2130
Author(s):  
Woo Geun Cheon ◽  
Jong-Seong Kug
Keyword(s):  
Ocean Circulation ◽  
North Atlantic ◽  
North Pacific ◽  
Global Ocean ◽  
The North ◽  
Westerly Winds ◽  
The North Atlantic ◽  
Global Ocean Circulation ◽  
The Antarctic ◽  
The North Pacific

AbstractIn the framework of a sea ice–ocean general circulation model coupled to an energy balance atmospheric model, an intensity oscillation of Southern Hemisphere (SH) westerly winds affects the global ocean circulation via not only the buoyancy-driven teleconnection (BDT) mode but also the Ekman-driven teleconnection (EDT) mode. The BDT mode is activated by the SH air–sea ice–ocean interactions such as polynyas and oceanic convection. The ensuing variation in the Antarctic meridional overturning circulation (MOC) that is indicative of the Antarctic Bottom Water (AABW) formation exerts a significant influence on the abyssal circulation of the globe, particularly the Pacific. This controls the bipolar seesaw balance between deep and bottom waters at the equator. The EDT mode controlled by northward Ekman transport under the oscillating SH westerly winds generates a signal that propagates northward along the upper ocean and passes through the equator. The variation in the western boundary current (WBC) is much stronger in the North Atlantic than in the North Pacific, which appears to be associated with the relatively strong and persistent Mindanao Current (i.e., the southward flowing WBC of the North Pacific tropical gyre). The North Atlantic Deep Water (NADW) formation is controlled by salt advected northward by the North Atlantic WBC.

scholarly journals Global biogeographic patterns in bipolar moss species

2017 ◽  
Vol 4 (7) ◽  
pp. 170147 ◽  
Author(s):  
E. M. Biersma ◽  
J. A. Jackson ◽  
J. Hyvönen ◽  
S. Koskinen ◽  
K. Linse ◽  
...  
Keyword(s):  
Large Scale ◽  
Common Species ◽  
Long Distance Dispersal ◽  
Stepping Stones ◽  
Long Distance ◽  
Antarctic Region ◽  
Moss Species ◽  
Biogeographic Patterns ◽  
Biogeographic Pattern ◽  
The Antarctic

A bipolar disjunction is an extreme, yet common, biogeographic pattern in non-vascular plants, yet its underlying mechanisms (vicariance or long-distance dispersal), origin and timing remain poorly understood. Here, combining a large-scale population dataset and multiple dating analyses, we examine the biogeography of four bipolar Polytrichales mosses, common to the Holarctic (temperate and polar Northern Hemisphere regions) and the Antarctic region (Antarctic, sub-Antarctic, southern South America) and other Southern Hemisphere (SH) regions. Our data reveal contrasting patterns, for three species were of Holarctic origin, with subsequent dispersal to the SH, while one, currently a particularly common species in the Holarctic ( Polytrichum juniperinum ), diversified in the Antarctic region and from here colonized both the Holarctic and other SH regions. Our findings suggest long-distance dispersal as the driver of bipolar disjunctions. We find such inter-hemispheric dispersals are rare, occurring on multi-million-year timescales. High-altitude tropical populations did not act as trans-equatorial ‘stepping-stones’, but rather were derived from later dispersal events. All arrivals to the Antarctic region occurred well before the Last Glacial Maximum and previous glaciations, suggesting that, despite the harsh climate during these past glacial maxima, plants have had a much longer presence in this southern region than previously thought.

scholarly journals Interannual response of global ocean hindcasts to a satellite-based correction of precipitation fluxes

2012 ◽  
Vol 9 (2) ◽  
pp. 611-648 ◽  
Author(s):  
A. Storto ◽  
I. Russo ◽  
S. Masina
Keyword(s):  
Ocean Circulation ◽  
Surface Current ◽  
Global Ocean ◽  
Surface Salinity ◽  
Near Surface ◽  
Convergence Zones ◽  
Circumpolar Current ◽  
The Tropics ◽  
Spatially Varying ◽  
The Antarctic

Abstract. We present a methodology to correct precipitation fluxes from the ECMWF atmospheric reanalysis (ERA-Interim) for oceanographic applications. The correction is performed by means of a spatially varying monthly climatological coefficient, computed within the period 1989–2008 by comparison between ERA-Interim and a satellite-based passive microwave precipitation product. ERA-Interim exhibits a systematic over-estimation of precipitation within the inter-tropical convergence zones (up to 3 mm d−1) and under-estimation at mid- and high- latitudes (up to −4 mm d−1). The correction has been validated within eddy-permitting resolution global ocean hindcasts (1989–2009), demonstrating the ability of our strategy in attenuating the 20-yr mean global EMP negative imbalance by 16%, reducing the near-surface salinity fresh bias in the Tropics up to 1 psu and improving the representation of the sea level interannual variability, with an SSH error decrease of 8%. The ocean circulation is also proved to benefit from the correction, especially in correspondence of the Antarctic Circumpolar Current, where the error in the near-surface current speed decreases by a 9%. Finally, we show that the correction leads to volume and freshwater transports that better agree with independent estimates.

scholarly journals Investigation of Changes of the Kinematic Parameters of Antarctic Tectonic Plate Using Data Observations of Permanent GNSS Stations

2017 ◽  
Vol 103 (1) ◽  
pp. 119-135 ◽  
Author(s):  
Kornylii Tretyak ◽  
Al-Alusi Forat ◽  
Yurii Holubinka
Keyword(s):  
Angular Velocity ◽  
Kinematic Parameters ◽  
Antarctic Region ◽  
Tectonic Plate ◽  
Euler Pole ◽  
The Mean ◽  
Using Data ◽  
Gnss Permanent Stations ◽  
The Antarctic

Abstract The paper describes a modified algorithm of determination of the Euler pole coordinates and angular velocity of the tectonic plate, considering the continuous and uneven distribution of daily measurements of GNSS permanent stations. Using developed algorithm were determined the mean position of Euler pole and angular velocity of Antarctic tectonic plate and their annual changes. As the input data, we used the results of observations, collected on 28 permanent stations of the Antarctic region, within the period from 1996 to 2014.

THE GENUSMICROCOSTATUSIN THE ANTARCTIC REGION

2010 ◽  
Vol 25 (2) ◽  
pp. 417-429 ◽  
Author(s):  
Bart Van de Vijver ◽  
Luc Ector ◽  
Myriam de Haan ◽  
Ralitsa Zidarova
Keyword(s):  
Antarctic Region ◽  
The Antarctic

Glacial climates in the Antarctic region during the late Paleogene: Evidence from northwest Tasmania, Australia

Geology ◽  
1993 ◽  
Vol 21 (2) ◽  
pp. 145 ◽  
Author(s):  
M. K. Macphail ◽  
E. A. Colhoun ◽  
K. Kiernan ◽  
D. Hannan
Keyword(s):  
Antarctic Region ◽  
The Antarctic
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