Variability of Oceanographic Conditions Between Ocean Station P and Swiftsure Bank off the Pacific Coast of Canada

1966 ◽  
Vol 23 (6) ◽  
pp. 825-868 ◽  
Author(s):  
N. P. Fofonoff ◽  
S. Tabata
Keyword(s):  
Wind Stress ◽  
Annual Variation ◽  
Pacific Coast ◽  
Vertical Movement ◽  
Ekman Transport ◽  
The Pacific ◽  
Total Transport ◽  
The Mean ◽  
Baroclinic Flow ◽  
Bottom Portion

Oceanographic observations taken along the line between Ocean Station P (50°N, 145°W) and Swiftsure Bank (48°32′N, 125°00′W) from January 1959 through January 1962 showed that the annual variation of temperature was determined primarily by the heat exchange across the surface and only secondarily by currents. Salinity variations were related to freshwater runoff from land and the component of Ekman transport normal to the coast. Variations of depths of isopycnal surfaces appeared to be related to the curl of wind stress, except near the coast. However, the observed vertical movement of isopycnal surfaces was much larger than that calculated from the wind stress. Near the coast, the vertical movement was related to the component of Ekman transport normal to the coast.The average total transport through the section, as calculated from the curl of the wind stress, was 5.8 million metric tons per second and was directed northward. The average baroclinic flow was 13 million metric tons per second. These transports were consistent if the mean depth of no motion was at 1400 m with southward flow in the bottom portion.

scholarly journals Fishing effects on elasmobranchs from the Pacific Coast of Colombia

2016 ◽  
Vol 21 (1) ◽  
pp. 9 ◽  
Author(s):  
Andrés Felipe Navia ◽  
Paola Andrea Mejía-Falla
Keyword(s):  
Species Composition ◽  
Pacific Coast ◽  
Trophic Levels ◽  
Functional Level ◽  
The Pacific ◽  
The Mean ◽  
The Stability ◽  
Large Predators ◽  
Average Catch ◽  
Index Of Diversity

<p>During 1995, 2001, 2003, 2004 and 2007; we studied the temporal variation in the structure of the elasmobranch assemblage along the Colombian Pacific coast using: the community index of diversity, heterogeneity, equitability, species composition, average catch sizes, and mean trophic levels. A total of 1 711 specimens from 19 species<br />(7 sharks and 12 rays) were collected during the 90 trawling operations. The number of species captured varied between 7 (1995) and 12 (2007) demonstrating a trend towards an imbalance in the assemblage attributes. In 1995, the mean trophic level (TLm) of the assemblage was 3.60, but in 2007 it decreased to 3.55 when the functional level of large predators was absent (TL ≥ 4). These results suggest changes in species composition, structural attributes, and a reduction of the highest functional level. Alterations to the catch proportions were also found: i.e. a greater abundance of rays of lower trophic levels. This study suggests an effect of trawling on the stability of this tropical coastal ecosystem.</p>

Buoyancy of Atlantic and Pacific Herring

1969 ◽  
Vol 26 (8) ◽  
pp. 2077-2091 ◽  
Author(s):  
Vivien M. Brawn
Keyword(s):  
Vertical Movement ◽  
Body Volume ◽  
Pacific Herring ◽  
Natural Conditions ◽  
The Pacific ◽  
In Captivity ◽  
The Mean ◽  
Total Body ◽  
Total Body Volume ◽  
The Relationship

Pacific and Atlantic herring after adjustment to water 36 cm deep had sinking-factors between 1000 and 1008 and showed an inverse relationship between oil content and swimbladder volume up to 12% oil. At higher oil contents a swimbladder volume between 2.6 and 3.0% of total body volume was maintained. The mean volumes and densities of various components of the Pacific herring held in captivity were: swimbladder gas 4.1% of total volume,.0013 g/ml; oil 3.5%,.926 g/ml; scales 0.5%, 1.966 g/ml; skeleton 1.2%, 1.993 g/ml; rest of fish 90.6%, 1.057 g/ml. These components on the average exerted upward forces of 41.4 and 3.3 dynes/ml of fish due to gas and oil, and downward forces of 4.6, 11.2, and 32.1 dynes/ml due to scales, skeleton, and the rest of the fish respectively. Under natural conditions herring usually have high oil contents so the relationship observed here suggests they have low swimbladder volumes. This combined with a duct direct from the swimbladder to the exterior and the lack of gas secretion would give the herring freedom of vertical movement and a low change of sinking factor with depth.

scholarly journals Global elevational, latitudinal, and climatic limits for termites and the redescription of Rugitermes laticollis Snyder (Isoptera: Kalotermitidae) from the Andean Highlands

Sociobiology ◽  
2015 ◽  
Vol 62 (3) ◽  
pp. 426 ◽  
Author(s):  
Rudolf H Scheffrahn
Keyword(s):  
Pacific Coast ◽  
Mean Annual Temperature ◽  
Termite Species ◽  
The Pacific ◽  
Zootermopsis Angusticollis ◽  
The Mean ◽  
Andean Highlands ◽  
Neotermes Chilensis ◽  
First Time ◽  
Recorded Temperature

We compile, map, and discuss global elevational, latitudinal, thermal, and rainfall extremes of termite localities from literature sources and unpublished records. Rugitermes laticollis from Ecuador and Bolivia occurs at higher elevation (2700-3600 m) than any other termite species.  Termites span the globe from 54.3°N (Zootermopsis angusticollis in British Columbia (B.C.), Canada) to 48.9°S (Porotermes quadricollis in Magdalena, Chile).  The coldest locality supporting termites (Reticulitermes sp.) is at Churn Creek, B.C., where the mean annual temperature is 4°C.   Lake Havasu City, Arizona, where Heterotermes aureus and Gnathamitermes perplexus occur, has the highest recorded temperature maximum (52°C) for a termite locality.  Cryptotermes brevis and Neotermes chilensis are endemic to the Pacific Coast of Peru and Chile where rain is essentially absent.  We further provide locality extremes for six termite families from six zoogeographical regions.  In addition, the winged imago of Ru. laticollis is redescribed and the soldier is described for the first time.

scholarly journals Moored Observations of Transport and Variability of Halmahera Sea Currents

2020 ◽  
Vol 50 (2) ◽  
pp. 471-488 ◽  
Author(s):  
Xiang Li ◽  
Dongliang Yuan ◽  
Zheng Wang ◽  
Yao Li ◽  
Corry Corvianawatie ◽  
...  
Keyword(s):  
Seasonal Cycle ◽  
Weak Current ◽  
Layer System ◽  
Indonesian Seas ◽  
The Pacific ◽  
Transport Calculation ◽  
Total Transport ◽  
The Pacific Ocean ◽  
The Mean ◽  
Sea Currents

AbstractThe ocean currents in the Halmahera Sea are studied using a subsurface mooring deployed in the Jailolo Strait from November 2015 to October 2017. The subtidal currents of the mooring measurements are characterized by a two-layer system, with the current variability below about 200 m in opposite phases to that in the upper layer. The mean along-strait velocity (ASV) is toward the Indonesian seas in the whole water column, producing an estimated mean transport of 2.44 ± 0.42 Sv (1 Sv ≡ 106 m3 s−1). The errors of the transport calculation based on the single mooring measurements are estimated to be less than 15% using simulations of high-resolution ocean models. A weak current is observed to flow northward during 2017 at the bottom of the strait. The ASV variability is found to be dominated by an annual cycle both in the upper and lower layers. The total transport, however, is dominated by semiannual variability because of the cancelation of the annual transports in the upper and lower layers. The variability of the transport is suggested to be driven by the pressure difference between the Pacific Ocean and the Indonesian seas, as evidenced by the agreement between the satellite pressure gradient and the two-layer transports. The transport of the Jailolo Strait during the 2015/16 super El Niño is found to be nearly the same as that during the 2016 La Niña, suggesting that the interannual variability of the transport is much smaller than the seasonal cycle.

Sensitivity of Western Boundary Transport at the Mean North Equatorial Current Bifurcation Latitude to Wind Forcing

2012 ◽  
Vol 42 (11) ◽  
pp. 2056-2072 ◽  
Author(s):  
Xuebin Zhang ◽  
Bruce Cornuelle ◽  
Dean Roemmich
Keyword(s):  
Wind Stress ◽  
Time Lag ◽  
Surface Wind ◽  
North Equatorial Current ◽  
Western Boundary ◽  
Adjoint Sensitivity ◽  
Surface Wind Stress ◽  
The Pacific ◽  
The Pacific Ocean ◽  
The Mean

Abstract The bifurcation of the North Equatorial Current (NEC) plays an important role in the heat and water mass exchanges between the tropical and subtropical gyres in the Pacific Ocean. The variability of western boundary transport (WBT) east of the Philippine coast at the mean NEC bifurcation latitude (12°N) is examined here. A tropical Pacific regional model is set up based on the Massachusetts Institute of Technology general circulation model and its adjoint, which calculates the sensitivities of a defined meridional transport to atmospheric forcing fields and ocean state going backward in time. The adjoint-derived sensitivity of the WBT at the mean NEC bifurcation latitude to surface wind stress is dominated by curl-like patterns that are located farther eastward and southward with increasing time lag. The temporal evolution of the adjoint sensitivity of the WBT to wind stress resembles wind-forced Rossby wave dynamics but propagating with speeds determined by the background stratification and current, suggesting that wind-forced Rossby waves are the underlying mechanism. Interannual-to-decadal variations of the WBT can be hindcast well by multiplying the adjoint sensitivity and the time-lagged wind stress over the whole model domain and summing over time lags. The analysis agrees with previous findings that surface wind stress (especially zonal wind stress in the western subtropical Pacific) largely determines the WBT east of the Philippines, and with a time lag based on Rossby wave propagation. This adjoint sensitivity study quantifies the contribution of wind stress at all latitudes and longitudes and provides a novel perspective to understand the relationship between the WBT and wind forcing over the Pacific Ocean.

Philometra chilensis (Nematoda, Philometridae) affects the fecundity of the red cusk-eel, Genypterus chilensis (Guichenot) (Pisces, Ophidiidae) in Chile

2011 ◽  
Vol 56 (2) ◽  
Author(s):  
Rosa Chávez ◽  
Marcelo Oliva
Keyword(s):  
Pacific Coast ◽  
Total Body Length ◽  
Infected Fish ◽  
Intensity Of Infection ◽  
Mean Intensity ◽  
The Pacific ◽  
The Mean ◽  
Total Body ◽  
Partial Spawner ◽  
Genypterus Chilensis

AbstractThe occurrence of the dracunculoid nematode Philometra chilensis Moravec, Chávez et Oliva, 2011 (Philometridae) infecting the ovary of the red cusk-eel, Genypterus chilensis (Guichenot), off the Pacific coast of northern Chile is reported. A sample of 266 fish specimens (total body length 34–96 cm) revealed the nematode overall prevalence (April 2007) of this parasite to be 18.5% and the mean intensity of infection 17.9 (SD = 30.8). All infected fish were mature females. The present results suggest that infection by the nematode shows seasonality and coincides with specific reproductive stages of the red cusk-eel, a partial spawner, and as a result the infection can affect the reproductive success of the host.

The Philological Association of The Pacific Coast

PMLA ◽  
1935 ◽  
Vol 50 (4) ◽  
pp. 1373-1374
Keyword(s):  
Annual Meeting ◽  
Pacific Coast ◽  
Stanford University ◽  
The Pacific

The thirty-seventh annual meeting of the Philological Association of the Pacific Coast was held at Stanford University, California, on November 29 and 30, 1935.

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