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. 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. 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 Cetacean strandings along the Pacific and Caribbean coasts of Nicaragua from 2014 to 2021

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Joëlle De Weerdt ◽  
Eric Angel Ramos ◽  
Etienne Pouplard ◽  
Marc Kochzius ◽  
Phillip Clapham
Keyword(s):  
Marine Mammals ◽  
Sperm Whale ◽  
Distribution Patterns ◽  
Sperm Whales ◽  
The Pacific ◽  
Toothed Whale ◽  
Beaked Whales ◽  
Causes Of Mortality ◽  
Cuvier’S Beaked Whale ◽  
Stenella Attenuata

AbstractDocumenting marine mammal strandings provides important information needed to understand the occurrence and distribution patterns of species. Here, we report on strandings of cetaceans on the Pacific (n = 11) and Caribbean (n = 2) coasts of Nicaragua, documented opportunistically from 2014 to 2021. Strandings included three species of baleen whale (blue whale Balaenoptera musculus, Bryde’s whale Balaenoptera edeni, humpback whale Megaptera novaeangliae) and five species of toothed whale (dwarf sperm whale Kogia sima, Guiana dolphin Sotalia guianensis, pantropical spotted dolphin Stenella attenuata, spinner dolphin Stenella longirostris, Cuvier’s beaked whale Ziphius cavirostris). These are the first published accounts of blue whales, Bryde’s whales, dwarf sperm whales, and Cuvier’s beaked whales in Nicaraguan waters. Limited resources and the advanced decomposition of animals prevented necropsies in most cases, the identification of the causes of mortality in all cases, and the species identification of two dolphins. Information derived from these stranding events offers new insights into the occurrence of marine mammals on the Pacific and Caribbean coasts of Nicaragua and Central America.

scholarly journals Climate variability impacts on diversification processes in a biodiversity hotspot: a phylogeography of ancient pseudoscorpions in south-western Australia

2019 ◽  
Vol 186 (4) ◽  
pp. 934-949 ◽  
Author(s):  
Danilo Harms ◽  
J Dale Roberts ◽  
Mark S Harvey
Keyword(s):  
Phylogenetic Analyses ◽  
Distribution Patterns ◽  
Biodiversity Hotspot ◽  
Molecular Dating ◽  
Environmental Niche ◽  
Ecological Niche Models ◽  
The South ◽  
Niche Modelling ◽  
South West ◽  
Western Division

Abstract The south-western division of Australia is the only biodiversity hotspot in Australia and is well-known for extreme levels of local endemism. Climate change has been identified as a key threat for flora and fauna, but very few data are presently available to evaluate its impact on invertebrate fauna. Here, we derive a molecular phylogeography for pseudoscorpions of the genus Pseudotyrannochthonius that in the south-west are restricted to regions with the highest rainfall. A dated molecular phylogeny derived from six gene fragments is used for biogeographic reconstruction analyses, spatial mapping, environmental niche-modelling, and to infer putative species. Phylogenetic analyses uncover nine clades with mostly allopatric distributions and often small linear ranges between 0.5 and 130 km. Molecular dating suggests that the origins of contemporary diversity fall into a period of warm/humid Palaeogene climates, but splits in the phylogeny coincide with major environmental shifts, such as significant global cooling during the Middle Miocene. By testing several models of historical biogeography available for the south-west, we determine that Pseudotyrannochthonius is an ancient relict lineage that principally follows a model of allopatric speciation in mesic zone refugia, although there are derivations from this model in that some species are older and distribution patterns more complex than expected. Ecological niche models indicate that drier and warmer future climates will lead to range contraction towards refugia of highest rainfall, probably mimicking past variations that have generated high diversity in these areas. Their conservation management will be crucial for preserving the unique biodiversity heritage of the south-west.

scholarly journals Amplitudes of surface waves and magnitudes of shallow earthquakes*

1945 ◽  
Vol 35 (1) ◽  
pp. 3-12
Author(s):  
B. Gutenberg
Keyword(s):  
Absorption Coefficient ◽  
Surface Waves ◽  
Epicentral Distance ◽  
Pacific Basin ◽  
Depth Of Focus ◽  
Intermediate Depth ◽  
Station Corrections ◽  
The Pacific ◽  
Shallow Earthquakes

Summary. A study of amplitudes of surface waves having periods of about 20 seconds is employed to improve the calculation of magnitudes of distant shallow earthquakes. Table 3 gives station corrections; table 4, revised figures for the effect of epicentral distance. It is found that for epicentral distances between about 20° and 175° the average observed amplitudes correspond closely to those calculated with an absorption coefficient k = 0.0003 per km. For paths completely outside or inside the Pacific Basin, k = 0.0002± per km., while for paths tangent to its boundary the amplitudes of surface waves with periods of about 20 seconds may be reduced by two-thirds or more (in extreme cases by almost nine-tenths) through reflection or refraction of energy; such seismograms of shallow shocks may be taken as indicating intermediate depth of focus.

Distribution patterns of disjunct and endemic vascular plants in the interior wetbelt of northwest North AmericaThis paper is one of a selection of papers published as part of the special Schofield Gedenkschrift.

Botany ◽  
2010 ◽  
Vol 88 (4) ◽  
pp. 409-428 ◽  
Author(s):  
Curtis R. Björk
Keyword(s):  
Vascular Plants ◽  
Distribution Patterns ◽  
South Coast ◽  
Ice Age ◽  
Annual Precipitation ◽  
Mean Annual Precipitation ◽  
North Coast ◽  
The Pacific ◽  
Inland Northwest ◽  
Wet Climate

A region of contrastively wetter and milder climate occurs in inland northwest North America, separated from similar climates of the Pacific coast by 200–400 km. Researchers have long noted that numerous vascular plants divide their ranges between the interior wetbelt and coastal regions, although many such disjunctions have hitherto gone undocumented. Here I summarize all vascular plants shared between coastal and interior wetbelt regions, disjunct by at least 200 km. These disjunct taxa are assigned to north-coast and south-coast lists according to whether the coastal portions of the ranges occur primarily north or south of the southern limits of maximum continental glaciation. A list of interior wetbelt endemic taxa is also presented, focusing on those that occur at forested elevations. Presence/absence for coastal disjunct and endemic taxa were assigned to grid of 1° × 1° latitude–longitude cells. Using this grid, concentrations of disjunct and endemic taxa were detected, and total values per cell were tested in linear regression for a relationship to mean annual precipitation. In total, 116 coastal disjunct taxa were detected, 31 of them north-coastal and 85 south-coastal. Interior wetbelt endemic and subendemic taxa total 95, and of these, 46 were found primarily at forested elevations. North-coast taxa were found over a wide latitudinal range both north and south of the glacial limits, and their distribution had a weak positive relationship with annual precipitation. South-coast and endemic taxa were found mostly south of the glacial limits, and their distribution did not correlate to annual precipitation. The greatest concentrations of south coastal disjunct and endemic taxa occurred in the Clearwater region of north-central Idaho; a region noted by previous researchers to be a likely ice-age refugium for wet-climate dependent plants and animals. Inferences are made from these patterns, both for biogeographical understanding of the roles played by the interior wetbelt and some regions connecting to the coast, as well as for preservation of biodiversity and ecosystem continuity.

scholarly journals Antarctic ice-shelf calving triggered by the Honshu (Japan) earthquake and tsunami, March 2011

2011 ◽  
Vol 57 (205) ◽  
pp. 785-788 ◽  
Author(s):  
Kelly M. Brunt ◽  
Emile A. Okal ◽  
Douglas R. MacAyeal
Keyword(s):  
Pacific Ocean ◽  
Northern Hemisphere ◽  
European Space Agency ◽  
Observational Evidence ◽  
Ice Shelf ◽  
Wave Impact ◽  
Space Agency ◽  
The Pacific ◽  
The Pacific Ocean ◽  
The Antarctic

AbstractWe use European Space Agency Envisat data to present the first observational evidence that a Northern Hemisphere tsunami triggered Antarctic ice-shelf calving more than 13 000 km away. The Honshu tsunami of 11 March 2011 traversed the Pacific Ocean in <18 hours where it impinged on the Sulzberger Ice Shelf, resulting in the calving of 125 km2 of ice from a shelf front that had previously been stable for >46 years. This event further illustrates the growing evidence of ocean-wave impact on Antarctic calving and emphasizes the teleconnection between the Antarctic ice sheet and events as far away as the Northern Hemisphere.

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