Circulation in Antarctic waters as revealed by iceberg tracks 1972–1983

Polar Record ◽  
1984 ◽  
Vol 22 (138) ◽  
pp. 263-269 ◽  
Author(s):  
Paul Tchernia ◽  
Pierre François Jeannin
Keyword(s):  
Ross Sea ◽  
Singular Points ◽  
Weddell Sea ◽  
West Wind ◽  
East Wind ◽  
Antarctic Waters ◽  
Underlying Causes

AbstractBetween February 1972 and January 1983, successively using positioning satellites Eole, Nimbus F, Tiros N-Argos, movements of 21 Antarctic icebergs were monitored daily from radio transmissions; 17 of the bergs were followed over periods of 228–828 days through distances of 1600 to 8000 km (2000 to 5000 nautical miles, nm). Mean daily positions, calculated from several observations, were accurate to less than 5.5 km (3 nm) for Eole and Nimbus, 0.9 km (0.5 nm) for Argos. Grouped into three areas (Weddell Sea, Enderby Land to Adelie Land, Ross Sea), the trajectories cover four fifths of the continental periphery. Movements clearly indicate singular points along the boundary between the two circumpolar currents, the East Wind and West Wind drifts, and variations in the strength and direction of flow of these currents; submarine topography and other underlying causes are suggested.

scholarly journals On tho proportions of the prevailing winds, the mean temperature, and depth of rain in the climate of London, computed through a cycle of Eighteen Years, or periods of the Moon’s declination

1843 ◽  
Vol 4 ◽  
pp. 300-300
Keyword(s):  
The Moon ◽  
Fair Weather ◽  
North West ◽  
West Wind ◽  
North East ◽  
East Wind ◽  
The North ◽  
The Common ◽  
The Mean ◽  
Solar Influence

In this paper the author investigates the periodical variations of the winds, rain and temperature, corresponding to the conditions of the moon’s declination, in a manner similar to that he has already followed in the case of the barometrical variations, on a period of years extending from 1815 to 1832 inclusive. In each case he gives tables of the average quantities for each week, at the middle of which the moon is in the equator, or else has either attained its maximum north or south declination. He thus finds that a north-east wind is most promoted by the constant solar influence which causes it, when the moon is about the equator, going from north to south; that a south-east wind, in like manner, prevails most when the moon is proceeding to acquire a southern declination ; that winds from the south and west blow more when the moon is in her mean degrees of declination, going either way, than with a full north or south declination ; and that a north-west wind, the common summer and fair weather wind of the climate, affects, in like manner, the mean declination, in either direction, in preference to the north or south, and most when the moon is coming north. He finds the average annual depth of rain, falling in the neighbourhood of London, is 25’17 inches.

Holodentata gen. nov. (Isopoda: Asellota: Paramunnidae) with a description of two new species: H. caeca and H. triangulata from the Southern Ocean

Zootaxa ◽  
2009 ◽  
Vol 2096 (1) ◽  
pp. 395-412 ◽  
Author(s):  
BRENDA LÍA DOTI ◽  
MADHUMITA CHOUDHURY ◽  
ANGELIKA BRANDT
Keyword(s):  
New Species ◽  
Southern Ocean ◽  
Dorsal View ◽  
Type Species ◽  
New Genus ◽  
Ross Sea ◽  
Weddell Sea ◽  
Two New Species

A new genus of Paramunnidae, Holodentata (type species: Paramunna gaussi Vanhöffen, 1914) is erected. The new genus comprises two new species: H. caeca, from the deep Weddell Sea and H. triangulata, from the Ross Sea. The new genus is distinguished by the following characters: article 3 of the antenna short and with strong denticles, mandible palp absent, article 2 of maxilliped palp longest, coxal plates visible in dorsal view in all pereonites, pleotelson broad and laterally denticulated.

scholarly journals Antarctic sea ice variability and trends, 1979–2010

2012 ◽  
Vol 6 (2) ◽  
pp. 931-956 ◽  
Author(s):  
C. L. Parkinson ◽  
D. J. Cavalieri
Keyword(s):  
Indian Ocean ◽  
Sea Ice ◽  
Ross Sea ◽  
Ice Cover ◽  
Weddell Sea ◽  
The Arctic ◽  
Future Research ◽  
Positive Trend ◽  
Antarctic Sea Ice ◽  
Ice Coverage

Abstract. In sharp contrast to the decreasing sea ice coverage of the Arctic, in the Antarctic the sea ice cover has, on average, expanded since the late 1970s. More specifically, satellite passive-microwave data for the period November 1978–December 2010 reveal an overall positive trend in ice extents of 17 100 ± 2300 km2 yr−1. Much of the increase, at 13 700 ± 1500 km2 yr−1, has occurred in the region of the Ross Sea, with lesser contributions from the Weddell Sea and Indian Ocean. One region, that of the Bellingshausen/Amundsen Seas, has, like the Arctic, instead experienced significant sea ice decreases, with an overall ice extent trend of −8200 ± 1200 km2 yr−1. When examined through the annual cycle over the 32-yr period 1979–2010, the Southern Hemisphere sea ice cover as a whole experienced positive ice extent trends in every month, ranging in magnitude from a low of 9100 ± 6300 km2 yr−1 in February to a high of 24 700 ± 10 000 km2 yr−1 in May. The Ross Sea and Indian Ocean also had positive trends in each month, while the Bellingshausen/Amundsen Seas had negative trends in each month, and the Weddell Sea and Western Pacific Ocean had a mixture of positive and negative trends. Comparing ice-area results to ice-extent results, in each case the ice-area trend has the same sign as the ice-extent trend, but differences in the magnitudes of the two trends identify regions with overall increasing ice concentrations and others with overall decreasing ice concentrations. The strong pattern of decreasing ice coverage in the Bellingshausen/Amundsen Seas region and increasing ice coverage in the Ross Sea region is suggestive of changes in atmospheric circulation. This is a key topic for future research.

The west wind vs the east wind: instructional leadership model in China

2017 ◽  
Vol 55 (2) ◽  
pp. 186-206 ◽  
Author(s):  
Haiyan Qian ◽  
Allan Walker ◽  
Xiaojun Li
Keyword(s):  
Instructional Leadership ◽  
Leadership Practices ◽  
School Principals ◽  
Social Contexts ◽  
Three Dimensions ◽  
The West ◽  
Content Type ◽  
West Wind ◽  
East Wind ◽  
Context Specific

Purpose The purpose of this paper is to develop a preliminary model of instructional leadership in the Chinese educational context and explore the ways in which Chinese school principals locate their instructional-leadership practices in response to traditional expectations and the requirements of recent reforms. Design/methodology/approach In-depth interviews were conducted with 22 selected primary school principals in Shenzhen and Guangzhou. A qualitative analysis was conducted to categorize the major leadership practices enacted by these principals. Findings An initial model of instructional leadership in China with six major dimensions is constructed. The paper also illustrates and elaborates on three dimensions with the greatest context-specific meanings for Chinese principals. Originality/value The paper explores the ways in which Chinese principals enact their instructional leadership in a context in which “the west wind meets the east wind”; that is, when they are required to accommodate both imported reform initiatives and traditional expectations. The paper contributes to the sparse existing research on principals’ instructional leadership in non-western cultural and social contexts.

Chapter 2.1b Ferrar Large Igneous Province: petrology

2021 ◽  
pp. M55-2018-39 ◽  
Author(s):  
David H. Elliot ◽  
Thomas. H. Fleming
Keyword(s):  
Ross Sea ◽  
Lower Jurassic ◽  
Weddell Sea ◽  
Geochemical Characteristics ◽  
Large Igneous Province ◽  
Geographical Pattern ◽  
Chemical Type ◽  
Igneous Province ◽  
Intrusive Rocks ◽  
Basic Rocks

AbstractThe Lower Jurassic Ferrar Large Igneous Province consists predominantly of intrusive rocks, which crop out over a distance of 3500 km. In comparison, extrusive rocks are more restricted geographically. Geochemically, the province is divided into the Mount Fazio Chemical Type, forming more than 99% of the exposed province, and the Scarab Peak Chemical Type, which in the Ross Sea sector is restricted to the uppermost lava. The former exhibits a range of compositions (SiO2 = 52–59%; MgO = 9.2–2.6%; Zr = 60–175 ppm; Sri = 0.7081–0.7138; εNd = −6.0 to −3.8), whereas the latter has a restricted composition (SiO2 = c. 58%; MgO = c. 2.3%; Zr = c. 230 ppm; Sri = 0.7090–0.7097; εNd = −4.4 to −4.1). Both chemical types are characterized by enriched initial isotope compositions of neodymium and strontium, low abundances of high field strength elements, and crust-like trace element patterns. The most basic rocks, olivine-bearing dolerites, indicate that these geochemical characteristics were inherited from a mantle source modified by subduction processes, possibly the incorporation of sediment. In one model, magmas were derived from a linear source having multiple sites of generation each of which evolved to yield, in sum, the province-wide coherent geochemistry. The preferred interpretation is that the remarkably coherent geochemistry and short duration of emplacement demonstrate derivation from a single source inferred to have been located in the proto-Weddell Sea region. The spatial variation in geochemical characteristics of the lavas suggests distinct magma batches erupted at the surface, whereas no clear geographical pattern is evident for intrusive rocks.

XX.—On a See-Saw of Barometric Pressure, Temperature, and Wind Velocity between the Weddell Sea and the Ross Sea

1915 ◽  
Vol 35 ◽  
pp. 203-216
Author(s):  
R. C. Mossman
Keyword(s):  
South America ◽  
Wind Velocity ◽  
Air Temperature ◽  
Ross Sea ◽  
Barometric Pressure ◽  
Meteorological Conditions ◽  
Weddell Sea ◽  
The Other ◽  
The Subject ◽  
The One

In the course of a large inquiry on the inter-relations between the meteorological conditions in Antarctica and the Southern Ocean, on the one hand, and those prevailing in the southern continents, more especially South America, on the other, there has come to light an interesting see-saw between the barometric pressure, air temperature, and wind velocity in the Weddell and the Boss Seas. The above inquiry, which I hope to lay before this Society shortly, refers to the eight-year period 1902–09; and since the present paper deals with the years 1902, 1903, 1911, and 1912, I have thought it better to make it the subject of a separate communication. The positions of these stations and others where observations have been made are shown on the accompanying map, for which I am indebted to Dr H. R. Mill. The figures within the rings give the number of years covered by the records at the various places.

Fine structure and biology of Cryothecomonas gen. nov. (Protista incertae sedis) from the ice biota

1991 ◽  
Vol 69 (4) ◽  
pp. 1048-1070 ◽  
Author(s):  
Helge A. Thomsen ◽  
Kurt R. Buck ◽  
Patricia A. Bolt ◽  
David L. Garrison
Keyword(s):  
New Genus ◽  
Size Range ◽  
Morphological Characteristics ◽  
Lateral Position ◽  
Weddell Sea ◽  
Heterotrophic Flagellates ◽  
Unique Combination ◽  
Taxonomic Level ◽  
Incertae Sedis ◽  
Antarctic Waters

The morphology and ultrastructure of four species of Cryothecomonas gen.nov. (Protista incertae sedis) in material from the Weddell Sea, Antarctica, and the Isefjord, Denmark, are described. These heterotrophic flagellates, which were initially observed in association with sea ice, display a unique combination of morphological characteristics. At present it is impossible to assign the new genus to an existing higher taxonomic level of protistan flagellates. Cryothecomonas species are furnished with a close-fitting multilayered theca. The two naked anterior flagella emerge through narrow thecal funnels. A transitional helix is part of the flagellar transition zone. A conspicuous cytostome is located in a posterior (lateral) position. Food uptake is mediated through the extension of cytostomal pseudopodia. The nucleus is anteriorly located and contains a conspicuous nucleolus and distinct areas of chromatin. Mitochondrial cristae are tubular. Cryothecomonas species feed on cells in the size range 2–4.5 μm (e.g., algal flagellates). Data are presented on the abundance of Cryothecomonas armigera sp.nov. in Antarctic waters.

THE PETROLEUM POTENTIAL OF ANTARCTICA AND ITS CONTINENTAL MARGIN

1981 ◽  
Vol 21 (1) ◽  
pp. 99
Author(s):  
P. J. Cameron
Keyword(s):  
Continental Margin ◽  
Ross Sea ◽  
Mineral Resources ◽  
Weddell Sea ◽  
East Antarctica ◽  
Petroleum Exploration ◽  
Oil Accumulation ◽  
Petroleum Potential ◽  
Late Mesozoic ◽  
West Antarctic

On the basis of geological comparison and analogy with other Gondwanaland continents, four regions of Antarctica and its continental margin offer potential petroleum-bearing basins.The area of the Weddell Sea, Byrd subglacial basin and Ross Sea is analogous to the area east of the Andes Mountains in Argentina and offers good petroleum potential.The divergent continental margin of East Antarctica is analogous to the southern Australian and East Brazilian margins and its continental shelf is likely to contain Late Mesozoic basins, perhaps with a variety of reservoir systems, having good petroleum potential.The wide continental shelves of the Bellinghausen and Amundsen seas on the West Antarctic margin may also present favourable areas of petroleum exploration. Large intracratonic basins in East Antarctica, although possibly geologically favourable for oil accumulation, lie beneath thick ice, are largely unknown, and are the least prospective of the four areas.The exploitation of any Antarctic mineral resources will require the resolution of sovereignty claims to Antarctica at present excluded from the Antarctic Treaty.

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