scholarly journals Diversity of late Neogene Monachinae (Carnivora, Phocidae) from the North Atlantic, with the description of two new species

2018 ◽  
Vol 5 (3) ◽  
pp. 172437 ◽  
Author(s):  
Leonard Dewaele ◽  
Carlos Mauricio Peredo ◽  
Pjotr Meyvisch ◽  
Stephen Louwye
Keyword(s):  
North America ◽  
North Atlantic ◽  
Late Miocene ◽  
East Coast ◽  
Type Specimens ◽  
The North ◽  
Late Neogene ◽  
New Material ◽  
The North Sea ◽  
The North Atlantic

While the diversity of ‘southern seals’, or Monachinae, in the North Atlantic realm is currently limited to the Mediterranean monk seal, Monachus monachus , their diversity was much higher during the late Miocene and Pliocene. Although the fossil record of Monachinae from the North Atlantic is mainly composed of isolated specimens, many taxa have been erected on the basis of fragmentary and incomparable specimens. The humerus is commonly considered the most diagnostic postcranial bone. The research presented in this study limits the selection of type specimens for different fossil Monachinae to humeri and questions fossil taxa that have other types of bones as type specimens, such as for Terranectes parvus . In addition, it is essential that the humeri selected as type specimens are (almost) complete. This questions the validity of partial humeri selected as type specimens, such as for Terranectes magnus . This study revises Callophoca obscura , Homiphoca capensis and Pliophoca etrusca , all purportedly known from the Lee Creek Mine, Aurora, North Carolina, in addition to their respective type localities in Belgium, South Africa and Italy, respectively. C. obscura is retained as a monachine seal taxon that lived both on the east coast of North America and in the North Sea Basin. However, H. capensis from North America cannot be identified beyond the genus level, and specimens previously assigned to Pl. etrusca from North America clearly belong to different taxa. Indeed, we also present new material and describe two new genera of late Miocene and Pliocene Monachinae from the east coast of North America: Auroraphoca atlantica nov. gen. et nov. sp., and Virginiaphoca magurai nov. gen. et nov. sp. This suggests less faunal interchange of late Neogene Monachinae between the east and west coasts of the North Atlantic than previously expected.

Growing Pacific Linkage with the Interannual Variability of North Atlantic Explosive Cyclogenesis

2021 ◽  
Author(s):  
Jacob John Stuivenvolt Allen ◽  
Simon S.-Y. Wang ◽  
Yoshimitsu Chikamoto ◽  
Jonathan D.D. Meyer ◽  
Zachary F. Johnson ◽  
...  
Keyword(s):  
North America ◽  
Interannual Variability ◽  
North Atlantic ◽  
High Latitude ◽  
East Coast ◽  
Wave Train ◽  
Baroclinic Instability ◽  
The North ◽  
Atmospheric Wave ◽  
The North Atlantic

Abstract Explosive cyclones (ECs), defined as developing extratropical cyclones that experience pressure drops of at least 24 hPa in 24 hours, are impactful weather events which occur along highly populated coastal regions in the eastern United States. These storms occur due to a combination of atmospheric and surface processes, such as jet stream intensification and latent heat release at the ocean surface. Even though previous literature has elucidated the role of these processes in EC formation, the sources of interannual variability that impact seasonal EC frequency are not well known. To analyze the sources of interannual variability, we track cases of ECs and dissect them into two spatial groups: those that formed near the east coast of North America (coastal) and those in the North Central Atlantic (high latitude). The frequency of high-latitude ECs is strongly correlated with the North Atlantic Oscillation, a well-known feature, whereas coastal EC frequency exhibits a growing relationship with an atmospheric wave-train emanating from the North Pacific in the last 30 years. This wave-train pattern of alternating high-and-low pressure resulted in resulted in heightened upper-level divergence and baroclinic instability along the east coast of North America. Using a coupled model experiment, we show that the tropical Pacific Ocean is the main driver of this atmospheric wave train and the subsequent enhancement seasonal baroclinic instability in the North Atlantic.

scholarly journals Rare Late Miocene Seal Taxa (Carnivora, Phocidae) from the North Sea Basin

2014 ◽  
Vol 48 (5) ◽  
pp. 419-432 ◽  
Author(s):  
I. Koretsky ◽  
S. Rahmat ◽  
N. Peters
Keyword(s):  
North Sea ◽  
North Atlantic ◽  
Late Miocene ◽  
Close Relationships ◽  
Western Europe ◽  
Northern Europe ◽  
The North ◽  
New Information ◽  
The North Sea ◽  
The North Atlantic

Abstract Rare Late Miocene Seal Taxa (Carnivora, Phocidae) from the North Sea Basin. Koretsky, I., Rahmat, S., Peters, N. - Th e discovery of new late Miocene fossil true seals from the North Sea Basin in Northern Europe provides important information regarding the radiation of monachines and phocines in the Eastern Atlantic. Examination of the first fossil seal remains from the Gram Formation, western Denmark, allowed redescriptions and emended diagnoses of several taxa. Analysis of diagnostic material recovered from western Denmark and Th e Netherlands shows the presence of at least three phocid genera and reveals new information on the taxonomic variability of true seals. Due to the close relationships that exist between these phocid faunas, a correlation was demonstrated between different localities of Northern and Western Europe and provides the opportunity to associate localities of the Western and Central Paratethys with the eastern and western shores of the North Atlantic. Morphological analyses of postcranial material identifi ed three new late Miocene species (Pontophoca jutlandica, Subfamily Monachinae; Gryphoca nordica and Platyphoca danica, both Subfamily Phocinae), suggesting that the maximum evolutionary diversity of mid-Tertiary phocids occurred first in the Paratethys and later in the North Atlantic Basins.

Notes on Power Operated Controls for Large Aircraft

1945 ◽  
Vol 49 (410) ◽  
pp. 51-54
Author(s):  
A. Gouge
Keyword(s):  
North America ◽  
North Atlantic ◽  
The North ◽  
The World ◽  
The North Atlantic ◽  
Large Aircraft

A Study of the air routes of the world brings out almost at once the fact that some of the most difficult route are also the most attractive. For instance, the North Atlantic route which couples North America with Europe is certainly one of the most difficult in the world, but also by the fact that it couples two of the most densely populated, as well as the most wealthy groups of people in the world, one of the most attractive.

scholarly journals Climate-Driven Change in the North Atlantic and Arctic Oceans Can Greatly Reduce the Circulation of the North Sea

2018 ◽  
Vol 45 (21) ◽  
pp. 11,827-11,836 ◽  
Author(s):  
Jason Holt ◽  
Jeff Polton ◽  
John Huthnance ◽  
Sarah Wakelin ◽  
Enda O'Dea ◽  
...  
Keyword(s):  
North Sea ◽  
North Atlantic ◽  
The North ◽  
The North Sea ◽  
The North Atlantic

Edges and interactions beyond Europe

2018 ◽  
Author(s):  
Peter S. Wells ◽  
Naoise Mac Sweeney
Keyword(s):  
North America ◽  
Iron Age ◽  
North Atlantic ◽  
Cultural Practices ◽  
Raw Materials ◽  
Long Distance ◽  
The North ◽  
First Millennium ◽  
Temperate Europe ◽  
The North Atlantic

Iron Age Europe, once studied as a relatively closed, coherent continent, is being seen increasingly as a dynamic part of the much larger, interconnected world. Interactions, direct and indirect, with communities in Asia, Africa, and, by the end of the first millennium AD, North America, had significant effects on the peoples of Iron Age Europe. In the Near East and Egypt, and much later in the North Atlantic, the interactions can be linked directly to historically documented peoples and their rulers, while in temperate Europe the evidence is exclusively archaeological until the very end of the prehistoric Iron Age. The evidence attests to often long-distance interactions and their effects in regard to the movement of peoples, and the introduction into Europe of raw materials, crafted objects, styles, motifs, and cultural practices, as well as the ideas that accompanied them.

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