The Intermediate Depth Waters of the Tasman and Coral Seas. II.The 26.80σt surface

1960 ◽  
Vol 11 (2) ◽  
pp. 148 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Distribution Patterns ◽  
Intermediate Depth ◽  
The North ◽  
Winter Distribution ◽  
South West ◽  
Tasman Sea ◽  
Antarctic Convergence ◽  
Horizontal Mixing ◽  
The Antarctic ◽  
The Western Pacific

The distribution of salinity, dissolved oxygen, and phosphates on the 26.80 σt surface of the Tasman and Coral Seas is examined. The distribution patterns of these properties and the relations of salinity and phosphate and salinity and oxygen values are explained by horizontal mixing of three water types. These originated, one to the north of the Antarctic Convergence, one in the south-west Tasman, possibly in the Australian Bight, and one at the equator in the western Pacific. The major sinking regions and the circulation paths of subtropical waters in the Tasman Sea are deduced from their summer and winter distribution and from the topography of the 26.80 σt, surface.

The Intermediate Depth Waters of the Tasman and Coral Seas. I. The 27.20 σt Surface

1960 ◽  
Vol 11 (2) ◽  
pp. 127 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Dissolved Oxygen ◽  
Distribution Patterns ◽  
Equatorial Region ◽  
Intermediate Depth ◽  
Water Types ◽  
South West ◽  
The Pacific ◽  
Antarctic Convergence ◽  
Horizontal Mixing ◽  
The Antarctic

The distribution of salinity, dissolved oxygen, and phosphates on the 27.20 σt surface of the Tasman and Coral Seas is examined. Their distribution patterns and the relations of salinity and phosphate values on this σt surface are explained by the horizontal mixing of three water types. These originate, one at the Antarctic Convergence, one in the western equatorial region of the Pacific, and one in the south-west Pacific. From the distribution of these water types and the topography of the 27.20 σt surface, general features of the intermediate depth circulation of the Tasman and Coral Seas are deduced.

The Intermediate Depth Waters of the Tasman and Coral Seas. III. Succession of Water Types East of Port Hacking in 1957-1959

1962 ◽  
Vol 13 (1) ◽  
pp. 61 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Seasonal Cycle ◽  
Vertical Mixing ◽  
Maximum Intensity ◽  
Water Type ◽  
Intermediate Depth ◽  
Water Types ◽  
South West ◽  
The Pacific ◽  
Actual Movement ◽  
The Antarctic

The seasonal occurrences of three water types on the 27.20 and 26.80 σt, surfaces on a section east of Port Hacking, 153-160� E., and at certain stations north of this line are discussed. On the 27.20 σt, surface it is shown that the Pacific Equatorial Intermediate is found in maximum intensity during September-October at longitude 158-160� E. Subsequently it moves west and during April-June it occurs at longitude 153-157� E. The South-West Pacific Intermediate appears at maximum intensity during March-July at 158-160� E. but in September-February it moves west to longitude 152-154� E. The Antarctic Intermediate is only about 30% of the water type mixture and occurs at the eastern end of the section during December to April and at the western end (152-154� E.) during March-April. On the 26.80 σt, surface the Subtropical formed between 30 and 75% of the water type mixture and was the principal water type, though it was not possible to distinguish between the part formed by local vertical mixing and that formed by actual movement from the Subtropical Convergence. No seasonal cycle could be determined for the Upper Antarctic Intermediate which varied between 0 and 55% of the water type mixture. The Upper Equatorial Intermediate varied from 5 to 45% of the mixture and showed no seasonal cycle.

scholarly journals Exploitation and Conservation of Seals in South Georgia

Oryx ◽  
1958 ◽  
Vol 4 (6) ◽  
pp. 373-380 ◽  
Author(s):  
W. Nigel Bonner
Keyword(s):  
Heavy Precipitation ◽  
South Georgia ◽  
Average Temperature ◽  
North East ◽  
The North ◽  
Antarctic Convergence ◽  
Mean Wind Speed ◽  
Meteorological Observations ◽  
The Many ◽  
The Antarctic

Almost from the date of their discovery by Captain Cook in 1775 the seal stocks of South Georgia have formed the basis of a lucrative, though initially sporadic, industry.South Georgia lies between 54 degrees and 55 degrees South and between 36 degrees and 38 degrees West. Despite its low latitude it has an antarctic climate, being south of the Antarctic Convergence at all seasons of the year. True sea ice is probably never formed on any of its coasts though enormous quantities of brash ice from the many glaciers may frequently obstruct access to certain beaches. Meteorological observations are made at King Edward Cove, a sheltered spot on the north-east coast, which does not perhaps represent truly the severity of the climate. In 1953 the average temperature throughout the year was 35·6 degrees F. and the extreme minimum recorded was 10 degrees F. in July. Almost certainly the exposed parts of the coast, particularly on the south-west side, frequently experience temperatures below zero. Violent winds are common. In 1953 the mean wind-speed was 8·9 knots and precipitation, mostly in the form of snow, amounted to 1,257·6 mm. The pattern of the climate of South Georgia is delineated by the relatively low temperatures, the prevailing high winds and the heavy precipitation.

Phytogeography of the tropical north-east African mountains

Bothalia ◽  
1983 ◽  
Vol 14 (3/4) ◽  
pp. 525-532 ◽  
Author(s):  
I. Friis
Keyword(s):  
Distribution Patterns ◽  
The South ◽  
East African ◽  
North East ◽  
The North ◽  
South West ◽  
Unpublished Studies ◽  
Mountain System ◽  
Mountain Chain ◽  
The Individual

The tropical north-east African mountains are tentatively divided into four phytochoria, the formal rank of which is not defined. The division is based on patterns of distribution and endemism in the region. The recognition of a distinct Afromontane phytochorion is now well established (Chapman White, 1970; Werger, 1978; White, 1978). However, there is still very little information on the phytogeography of the individual mountains or mountain systems. This study hopes to fill a little of the gap by analysing distribution patterns and patterns of endemism in the flora of the tropical north-east African mountains. The north-east African mountain system is the largest in tropical Africa (see e.g. map in White, 1978). At the core of this system is the large Ethiopian massif, around which are located various mountains and mountain chains. These include the Red Sea Hills in the Sudan, the mountain chain in northern Somalia, the south-west Arabian mountains, and the Imatong mountains of south-east Sudan. The latter are often referred to the East African mountain system (White, 1978) but. as I will point out later, they also have a close connection with the south-west highlands of Ethiopia. The paper presents some results of my study of the mountain flora of tropical north-east Africa, particularly the forest species. Where no source is indicated, the data are from my own unpublished studies.

scholarly journals XV.—Atlantic Sponges collected by the Scottish National Antarctic Expedition

1915 ◽  
Vol 50 (2) ◽  
pp. 423-467 ◽  
Author(s):  
Jane Stephens
Keyword(s):  
Deep Water ◽  
Cape Of Good Hope ◽  
The North ◽  
South West ◽  
Gough Island ◽  
Antarctic Expedition ◽  
South West Coast ◽  
St Helena ◽  
The Antarctic ◽  
North And South

The sponges in the following report were collected in the North and South Atlantic during the Scotia's voyages to and from the Antarctic regions in the years 1902–1904.All the sponges in the collection were obtained off the south-west coast of Cape Colony, with the exception of five well-known species which were taken off St Helena, the Cape Verde Islands, and the Princesse Alice Bank. Only one specimen was dredged in deep water, namely, in 350 fathoms off the Princesse Alice Bank, while the remainder were taken between tide-marks to a depth of 30 fathoms.The collection contains thirty-five species, of which fifteen are described as new.To complete the list of sponges obtained by the Scotia in Atlantic waters, mention may be made here of one species which is not contained in this report. This species, Cladorhiza thomsoni, dredged in deep water between Gough Island and the Cape of Good Hope, has been described by Professor Topsent (24 and 25). It was taken at Station 468, 39° 48′ S., 2° 33′ E., depth 2770 fathoms.The five species above referred to, Leucandra crambessa, Aphrocallistes beatrix, Tethya lyncurium, Chondrosia plebeja and Chondrosia reniformis, call for no special remark. They have all been previously obtained in, or fairly near, the areas for which they are here recorded.

Geographical distribution of living planktonic foraminifera (Protozoa) off the east coast of Australia.

1988 ◽  
Vol 39 (1) ◽  
pp. 71 ◽  
Author(s):  
S Andrijanic
Keyword(s):  
Sea Water ◽  
Planktonic Foraminifera ◽  
Distribution Patterns ◽  
Water Masses ◽  
Individual Species ◽  
The South ◽  
The North ◽  
Warm Core ◽  
Tasman Sea ◽  
Eastern Australia

Major water masses found off eastern Australia can be identified by their planktonic foraminiferal faunas. A total of 83 surface and oblique plankton samples from two cruises, in spring (October) and summer (January), between Hobart at 44� S. and Townsville at 18� S. yielded 27 species belonging to four distinct faunas: 'tropical', 'warm subtropical', 'cool subtropical' and 'transitional'. The tropical fauna is characterized by Globigerinoides sacculifer at an abundance greater than 42% and the co- dominance of Globigerinoides conglobatus, and is associated with Coral Sea water of equatorial origin. The subtropical fauna can be subdivided into warm and cool elements. The warm-subtropical fauna, with G. sacculifer more abundant than Globigerinoides ruber, inhabits Coral and Tasman Sea waters. The cool-subtropical fauna is a mixture of the warm subtropical and the transitional faunas. The transitional fauna is dominated by Globorotalia inflata and Globigerina bulloides in the south Tasman Sea subantarctic waters. It characterizes the South West Tasman water as defined by Rochford (1957). These water masses can be clearly separated, and the extent of mixing determined by their foraminiferal fauna. The shifts in the boundaries between the faunal zones was evident between spring and summer. The boundary between the tropical and subtropical water corresponds to the tropical convergence and the subtropical/transitional boundary is the Tasman Front. During the spring cruise, a warm core eddy was identified by its warm subtropical foraminiferal fauna surrounded by a transitional fauna to the south and cool subtropical fauna to the north. This water body was near 32� S., which is consistent with the reported positions of eddies shed by the East Australian Current. The distribution patterns of individual species are discussed.

Introduction

1964 ◽  
Vol 281 (1384) ◽  
pp. 1-6 ◽  
Keyword(s):  
Surface Temperature ◽  
General Circulation ◽  
Cold Water ◽  
Antarctic Water ◽  
The South ◽  
Cold Zone ◽  
The North ◽  
Antarctic Convergence ◽  
Meteorological Observations ◽  
The Antarctic

The topic of this afternoon’s Discussion was proposed by a joint panel of the National Committees on Antarctic and Oceanic Research to see whether joint discussion of an outstanding problem would initiate further collaboration. The Antarctic Convergence is a fairly obvious partition round the southern half of the circumpolar ocean, marking where the cold water of the Antarctic surface layer comes up against warmer Subantarctic water. It is always found in more or less the same position and many authors have referred to it as an important climatological and zoogeographical boundary. The physical processes which give rise to it may have a bearing on events in the atmosphere as well as on the general circulation of the ocean. It is not a barrier, the Antarctic water sinks, mixes and continues to the north at a lower level; icebergs get across it, and animals too, but it is an interesting and significant frontier. It should have been rather easy in a country like ours, traditionally interested in the Antarctic and the oceans, to find speakers, but the little we know about the Antarctic Convergence tends to emphasize the lack of really precise information such as scientists like to have, and as convener of the discussion I ought to mention that today’s speakers are not very willing volunteers. The story begins with the report of the meteorological observations of the German South Polar Expedition of 1901–02, published, like most large reports of expeditions, some 20 years later. Professor W. Meinardus, studying the surface temperature observations in the Indian Antarctic sector, found that the decrease of temperature towards the south becomes noticeably slower south of 50° S. The contrast was sufficient to divide the west wind drift into a cold zone to the south and a warm one to the north. He recognized the boundary as a line along which the cold Antarctic water sinks below the warmer Snbantarctic water with a consequent rise in surface temperature towards the north of about 2 °C. Using the observations of other expeditions he was able to plot its latitude from 105° W to 80° E. The circumpolar voyage made by the R. R. S. Discovery II in the winter of 1932 showed that it is continuous round the continent.

Some Aspects of the Deep Circulation of the Tasman and Coral Seas

1960 ◽  
Vol 11 (2) ◽  
pp. 166 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
General Circulation ◽  
High Salinity ◽  
Late Nineteenth Century ◽  
Deep Circulation ◽  
Latitude Range ◽  
The North ◽  
South West ◽  
Tasman Sea ◽  
The Indian Ocean ◽  
North And South

Data from selected stations deeper than 2000 m in the Tasman and Coral Seas are used to prepare meridional sections of salinity, oxygen, and phosphate along the meridian 155� E. between latitudes 14� S. and 42� S., and zonal sections of the same properties between meridians 149� E. and 155� E. in the latitude range 14-15� S. Meridional changes in the salinity minimum, phosphate maximum, and deep salinity maximum indicate circulation below 1500 m. Utilizing all available data, the general circulation of these waters in the Tasman and Coral Seas as a whole is described. Phosphate-rich waters from the Equatorial Western Pacific and probably from the Indian Ocean are found distributed along the western margin to the north and south of the region, at about the 2000 m level. Below this level, well-oxygenated waters of high salinity, presumably from the South-West Pacific, enter the northern Tasman Sea, through the New Caledonian trench. By comparison of temperature, salinity, and oxygen values the depth of the sill connecting the Tasman and Coral Seas is estimated at 3000 m. Along the 155� E. meridian temperatures recorded during the late nineteenth century were warmer by 0. 15-0.3�C than those obtained recently.

Australian endemic Drosophila III. The inornata species-group

1978 ◽  
Vol 26 (1) ◽  
pp. 83 ◽  
Author(s):  
PA Parsons ◽  
IR Bock
Keyword(s):  
Western Australia ◽  
New South ◽  
South Australia ◽  
Distribution Patterns ◽  
Species Group ◽  
The North ◽  
Resistant Species ◽  
South West ◽  
South Wales ◽  
Group Species

Amongst Australian non-baitable Dvosophila species, the inornata group of the subgenus Scaptodrosophila dominates in southern Australia. Distribution patterns correspond to the temperate zone flora so that, with one exception, the northerly limit of the group occurs in the southern Queensland upland forests. Amongst non-baitables only inornata-group species occur in south-west Western Australia and South Australia, while the species-group dominates in Victoria and Tasmania. In eastern Victoria and New South Wales other Scaptodrosophila species occur in increasing numbers towards the north, although the inornata group remains dominant. Two species occur exclusively in south-west Western Australia, while one desiccation-resistant species is common on both sides of the Nullabor. Distribution and speciation patterns are discussed in relation to past climates.

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