scholarly journals Alcataenia longicervica sp. n. from murres, Uria lomvia (Linnaeus) and Uria aalge (Pontoppidan) in the North Pacific basin, with redescriptions of Alcataenia armillaris (Rudolphi, 1810) and Alcataenia meinertzhageni (Baer, 1956) (Cestoda: Dilepididae)

1984 ◽  
Vol 62 (10) ◽  
pp. 2044-2052 ◽  
Author(s):  
Eric P. Hoberg
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
Pacific Basin ◽  
North Atlantic Region ◽  
Uria Lomvia ◽  
Atlantic Region ◽  
The North ◽  
The Pacific ◽  
The North Pacific ◽  
North Pacific Basin

Alcataenia longicervica sp. n. (Cestoda: Dilepididae) is described from murres, Uria spp., in Alaska and other localities in the Pacific basin. From Alcataenia armillaris (Rudolphi, 1810), which it most closely resembles, A. longicervica is distinguished by larger size of organs (cirrus sac, vitelline gland, and seminal receptacle), greater number of testes, and extremely long neck. In specimens of A. longicervica there are 22–27 rostellar hooks distributed in two rows. Hooks in the anterior row measure 41–49 μm in length while those in the posterior are 38–48 μm. Two species of Alcataenia, A. armillaris and A. meinertzhageni (Baer, 1956), both characteristic cestodes of birds of the genus Uria Brisson, are redescribed from material from the North Pacific basin and are compared with descriptions of specimens from the North Atlantic region.

The genus Anonyx (Crustacea, Amphipoda) in the North Pacific and Arctic oceans: Anonyx compactus group

1989 ◽  
Vol 67 (8) ◽  
pp. 1945-1954 ◽  
Author(s):  
D. H. Steele
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
Pacific Region ◽  
North Atlantic Region ◽  
Atlantic Region ◽  
Normal Length ◽  
The North ◽  
North Pacific Region ◽  
The North Atlantic ◽  
The North Pacific

The Anonyx compactus group is characterized by the morphology of the inner ramus of the second uropod, which is of normal length and depth but is completely constricted distally and bears a long spine at the constriction. This group comprises eight species of which three, Anonyx attenuatus, Anonyx stappersi, and Anonyx stebbingi, are newly described. Anonyx stappersi was identified as Chironesimus debruyni by L. Stappers and A. stebbingi as A. ampulloides by T. R. R. Stebbing. Seven of these species are known from the North Pacific region, and three from the North Atlantic region, but none has a circumpolar distribution.

The genus Anonyx (Crustacea, Amphipoda) in the North Pacific and Arctic oceans: Anonyx laticoxae group

1986 ◽  
Vol 64 (11) ◽  
pp. 2603-2623 ◽  
Author(s):  
D. H. Steele
Keyword(s):  
New Species ◽  
North Atlantic ◽  
North Pacific ◽  
Pacific Region ◽  
North Atlantic Region ◽  
Atlantic Region ◽  
The North ◽  
North Pacific Region ◽  
The North Atlantic ◽  
The North Pacific

Thirteen species of the Anonyx laticoxae group (uropod 2 with the rami not broadened and with the inner ramus not constricted) are listed for the North Pacific region. Five new species, Anonyx schefferi, Anonyx stegnegeri, Anonyx gurjanovai, Anonyx hurleyi, and Anonyx petersoni are described. Anonyx japonicus is synonymized with Anonyx affinis, and Anonyx lebedi and A. orientalis are raised to full species. Eleven of these species are known only from the North Pacific region. Anonyx laticoxae and Anonyx affinis are the only two that are also found in the North Atlantic region.

Revision of the genus Anophryocephalus Baylis, 1922 from pinnipeds in the Holarctic, with descriptions of Anophryocephalus nunivakensis sp.nov. and A. eumetopii sp.nov. (Tetrabothriidae) and evaluation of records from the Phocidae

1991 ◽  
Vol 69 (6) ◽  
pp. 1653-1668 ◽  
Author(s):  
Eric P. Hoberg ◽  
Ann M. Adams ◽  
Robert L. Rausch
Keyword(s):  
Bering Sea ◽  
North Pacific ◽  
Pacific Basin ◽  
Genital Papilla ◽  
High Latitudes ◽  
Eumetopias Jubatus ◽  
The North ◽  
Phoca Largha ◽  
The North Pacific ◽  
North Pacific Basin

Anophryocephalus Baylis, 1922 is emended to include tetrabothriid cestodes with intricate scolices (paired auricular appendages and bothridial operculae), complex genital atria (muscular chamber ventral to the vagina; muscular pad adjacent to the aperture of the male canal), and atrophy of the dorsal osmoregulatory system. Anophryocephalus anophrys (type), A. skrjabini, and A. ochotensis are redescribed. Anophryocephalus nunivakensis sp.nov., from Phoca largha, has bothridial operculae with broad anterior apertures, an ovoid cirrus sac (57–95 μm in diameter), a ventrolaterally directed male canal (26–44 μm long in mature segments), and 26–56 testes. Anophryocephalus eumetopii sp.nov., from Eumetopias jubatus, has bothridial operculae with narrow, slitlike, diagonally directed apertures, a spheroidal cirrus sac (51–72 μm in diameter), a prominent genital papilla and ventrolaterally directed male canal (36–51 μm long in mature segments), and 32–66 testes. Postlarval ontogeny of the scolex among some species of Anophryocephalus appears similar to that known for Tetrabothrius spp., suggesting uniformity in morphogenesis of the holdfast among the Tetrabothriidae. Anophryocephalus spp. are typical parasites of pinnipeds in the Holarctic, and contrary to previous reports, A. skrjabini and A. ochotensis are exclusively parasites of Phoca spp. and Eumetopias jubatus, respectively, at high latitudes in the North Pacific basin and Bering Sea.

scholarly journals Multidecadal Fluctuation of the Wintertime Arctic Oscillation Pattern and Its Implication

2018 ◽  
Vol 31 (14) ◽  
pp. 5595-5608 ◽  
Author(s):  
Hainan Gong ◽  
Lin Wang ◽  
Wen Chen ◽  
Debashis Nath
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
Arctic Oscillation ◽  
Surface Air Temperature ◽  
Western North America ◽  
Oscillation Pattern ◽  
The North ◽  
The Pacific ◽  
The North Atlantic ◽  
The North Pacific

The multidecadal fluctuations in the patterns and teleconnections of the winter mean Arctic Oscillation (AO) are investigated based on observational and reanalysis datasets. Results show that the Atlantic center of the AO pattern remains unchanged throughout the period 1920–2010, whereas the Pacific center of the AO is strong during 1920–59 and 1986–2010 and weak during 1960–85. Consequently, the link between the AO and the surface air temperature over western North America is strong during 1920–59 and 1986–2010 and weak during 1960–85. The time-varying Pacific center of the AO motivates a revisit to the nature of the AO from the perspective of decadal change. It reveals that the North Pacific mode (NPM) and North Atlantic Oscillation (NAO) are the inherent regional atmospheric modes over the North Pacific and North Atlantic, respectively. Their patterns over the North Pacific and North Atlantic remain stable and change little with time during 1920–2010. The Atlantic center of the AO always resembles the NAO over the North Atlantic, but the Pacific center of the AO only resembles the NPM over the North Pacific when the NPM–NAO coupling is strong. These results suggest that the AO seems to be fundamentally rooted in the variability over the North Atlantic and that the annular structure of the AO very likely arises from the coupling of the atmospheric modes between the North Pacific and North Atlantic.

scholarly journals Impact of North Atlantic Freshwater Forcing on the Pacific Meridional Overturning Circulation under Glacial and Interglacial Conditions

2019 ◽  
Vol 32 (15) ◽  
pp. 4641-4659
Author(s):  
Hyo-Jeong Kim ◽  
Soon-Il An
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
Meridional Overturning Circulation ◽  
Global Ocean ◽  
Overturning Circulation ◽  
The North ◽  
Freshwater Forcing ◽  
The Pacific ◽  
Meridional Overturning ◽  
The North Pacific

Abstract The Pacific meridional overturning circulation (PMOC) is not well known compared to the Atlantic meridional overturning circulation (AMOC), due to its absence today. However, considering PMOC development under different climate conditions shown by proxy and modeling studies, a better understanding of PMOC is appropriate to properly assess the past and future climate change associated with global ocean circulation. Here, the PMOC response to freshwater forcing in the North Atlantic (NA) is investigated using an Earth system model of intermediate complexity under glacial (i.e., Last Glacial Maximum) and interglacial [i.e., preindustrial with/without inflow through Bering Strait (BS)] conditions. The water hosing over NA led to the shutdown of the AMOC, which accompanied an active PMOC except for the preindustrial condition with the opening BS, indicating that the emergence of the PMOC is constrained by the freshwater inflow through the BS, which hinders its destabilization through enhancing ocean stratification. However, the closure of the BS itself could not explain how the sinking motion is maintained in the North Pacific. Here we found that various atmospheric and oceanic processes are involved to sustain the active PMOC. First, an atmospheric teleconnection associated with the collapsed AMOC encouraged the evaporation in the sinking region, causing buoyancy loss at the surface of the North Pacific. Second, the strengthened subpolar gyre transported saltier water northward, enhancing dense water formation. Finally, the vigorous upwelling in the Southern Ocean enabled a consistent mass supply to the sinking region, with the aid of enhanced westerlies.

Nature of the Differences in the Intraseasonal Variability of the Pacific and Atlantic Storm Tracks: A Diagnostic Study

2006 ◽  
Vol 63 (10) ◽  
pp. 2602-2615 ◽  
Author(s):  
Yi Deng ◽  
Mankin Mak
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
Intraseasonal Variability ◽  
Storm Track ◽  
Late Winter ◽  
The North ◽  
The Pacific ◽  
The North Atlantic ◽  
Early Late ◽  
The North Pacific

Abstract On the basis of an intraseasonal variability index of storm track evaluated for 40 winters (1963–64 through 2003–04) of NCEP–NCAR reanalysis data, it is found that well-defined midwinter minimum [MWMIN; (midwinter maximum MWMAX)] occurs in 21 (8) winters over the North Pacific. In contrast, MWMIN (MWMAX) occurs in 4 (25) of the 40 winters over the North Atlantic. The power spectrum of such an index for the Pacific has a broad peak between 5 and 10 yr, whereas the spectrum of the index for the Atlantic has comparable power in two spectral bands: 2–2.8 and 3.5–8 yr. Over the North Pacific, the increase in the zonal asymmetry of the background baroclinicity as well as in the corresponding horizontal deformation of the time-mean jet from early/late winter to midwinter is distinctly larger in an MWMIN winter. Associated with these changes, there is a distinctly stronger barotropic damping rate in the January of an MWMIN winter. The increase in the net conversion rate of eddy kinetic energy from early/late winter to midwinter is much larger in an MWMAX winter than that in an MWMIN winter. Even though there is a modest increase in the barotropic damping from early/late winter to midwinter over the North Atlantic, it is overcompensated by a larger increase in the baroclinic conversion rate. That would result in MWMAX. These results are empirical evidences in support of a hypothesis that a significant enhancement of the barotropic damping relative to the baroclinic growth from early/late winter to midwinter is a major contributing factor to MWMIN of the Pacific storm track.

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