Northeast pacific and bering sea magnetic data, Juan De Fuca Strait, British Columbia to icy cape, Alaska

1975 ◽  
Author(s):  
1979 ◽  
Vol 36 (10) ◽  
pp. 1223-1227
Author(s):  
D. D. Lemon ◽  
P. H. LeBlond ◽  
T. R. Osborn

Seiche motions observed in San Juan Harbour with a bottom-mounted pressure gauge have been Fourier-analyzed and interpreted in terms of a theoretical model of oscillations in a rectangular basin with an exponential depth profile. Two of the observed periods (at 14.6 and 38.5 min) are identified with resonances of the basin; two other significant low frequency peaks (at 21 and 55 min) do not coincide with resonant periods of the basin and must be due to strong external forcing. Higher frequency fluctuations (20–160 s) are attributed to swell and to its subharmonic interactions with edge waves. Key words: water waves, seiches, mathematical model, Juan de Fuca Strait, British Columbia


1979 ◽  
Vol 16 (9) ◽  
pp. 1645-1657 ◽  
Author(s):  
Neville F. Alley ◽  
Steven C. Chatwin

The major Pleistocene deposits and landforms on southwestern Vancouver Island are the result of the Late Wisconsin (Fraser) Glaciation. Cordilleran glaciers formed in the Vancouver Island Mountains and in the Coast Mountains had advanced down Strait of Georgia to southeastern Vancouver Island after 19 000 years BP. The ice split into the Puget and Juan de Fuca lobes, the latter damming small lakes along the southwestern coastal slope of the island. During the maximum of the glaciation (Vashon Stade), southern Vancouver Island lay completely under the cover of an ice-sheet which flowed in a south-southwesterly direction across Juan de Fuca Strait, eventually terminating on the edge of the continental shelf. Deglaciation was by downwasting during which ice thinned into major valleys and the strait. Most upland areas were free of ice down to an elevation of 400 m by before 13 000 years BP. A possible glacier standstill and (or) resurgence occurred along Juan de Fuca Strait and in some interior upland valleys before deglaciation was complete. Glacial lakes occupied major valleys during later stages of deglaciation.


1965 ◽  
Vol 43 (11) ◽  
pp. 1409-1420 ◽  
Author(s):  
Thomas B. Widdowson

The genus Hedophyllum Setchell consists of one variable species, H. sessile (C. Ag.) Setchell. Field observations and experiments show that H. subsessile Setchell was based upon a form characteristic of the type species in the second summer of its life. H. spirale Yendo is reduced to synonymy with Laminaria bongardiana P. et R., and H. kuroshioense Segawa is transferred to the genus Laminaria.Observations of the genus in the field throughout most of its range in the northeast Pacific indicate morphological differences between populations in the areas east and west of Yakutat, in the Gulf of Alaska. These differences appear to be related to sea temperature.Morphological variations in populations of Hedophyllum studied along Juan de Fuca Strait appear to be caused by exposure to sunlight and the mechanical effects of wave action.


2021 ◽  
Author(s):  
Susan Allen ◽  
Tereza Jarnikova ◽  
Elise Olson ◽  
Debby Ianson

<p>Coastal regions by their very nature are dynamically diverse.  Within one geographical region there are often multiple areas dominated by substantially different dynamics that shape not only the physical characteristics but also the ecosystem.  The Salish Sea, in the northeast Pacific, is an excellent example with strongly tidally mixed regions, freshwater-dominated regions, and regions directly influenced by the open ocean.  These regions are generally well known and multiple disciplines refer to them with various boundaries and under various names.  Here we use unsupervised clustering on numerical model results to formalize these regional provinces.  The model is SalishSeaCast,  a three-dimensional real-time coupled bio-chem-physical model based on the NEMO framework.  We find that the regions clustered on ecosystem variables (phytoplankton biomass) spatially coincide with those clustered on physical variables, particularly the stratification as diagnosed by the halocline depth.  The clusters are robust across years with interannual variability manifesting mostly in changes in the size of the clusters.  As the clusters are dynamically distinct, they provide a natural framework on which to evaluate the model against observations.  We find that the model accurately simulates each of the major clusters.  The spatial and temporal resolution of the model can then characterize these different clusters more systematically than the observations, revealing biases associated with sparse sampling in the observations. Two examples will be given, one addressing a long-standing issue of the productivity gradient in the stratified main basin, the Strait of Georgia, and another concerning the seasonal cycle of productivity in the ocean-influenced Juan de Fuca Strait.</p>


1971 ◽  
Vol 28 (10) ◽  
pp. 1681-1681
Author(s):  
W. E. Barraclough ◽  
R. M. Wilson

The whitebait smelt Allosmerus elongatus (Ayres) is recorded from British Columbia for the first time on the basis of three specimens from Juan de Fuca Strait caught November 2, 1969.


Zootaxa ◽  
2019 ◽  
Vol 4700 (1) ◽  
pp. 1-29
Author(s):  
B. OTT ◽  
H. M. REISWIG ◽  
N. McDANIEL ◽  
R. HARBO

Collections of sponges by the late Dr. William C. Austin and the authors (N. McDaniel, R. Harbo and B. Ott) provided material for descriptions of new species from two genera of Poecilosclerida for shallow waters of Southern British Columbia, Canada and Northern Washington, USA: Lissodendoryx and Myxilla. There have been no new species of these two genera described for the Northeast Pacific since Laubenfels’ work in central California (Laubenfels 1930, 1932) and Lambe’s reports in 1893 to 1895 for Geological Survey of Canada sponge collections from British Columbia, Canada to the Bering Sea. We describe three new species of Lissodendoryx (Lissodendoryx) (Demospongiae, Poecilosclerida, Coelosphaeridae) and one new species of Myxilla (Myxilla) (Demospongiae, Poecilosclerida, Myxillidae): L. (L.) barkleyensis n. sp., L. (L.) littoralis n. sp., L. (L.) toxaraphida n. sp. and M. (M.) austini n. sp. Lissodendoryx (L.) barkleyensis n. sp. is cave-dwelling, has acanthostyles 112–260 µm, tornotes 107–177 µm, arcuate isochelas 8–28 µm and two sizes of sigmas 18–29, 26–55 µm. Lissodendoryx (L.) littoralis n. sp. fistulate habitus is adapted to muddy substrates similar to some Polymastia species also found commonly in the Northeast Pacific. It has subtylostyles 185–336 µm, tylotes 112–229 µm, arcuate isochelas 11–23 µm, and sigmas 30–75 µm. Lissodendoryx (L.) toxaraphida n. sp. is the only described Lissodendoryx species with raphides shaped like toxas. It has acanthostyles 140–286 µm, tornotes 143–195µm, arcuate isochelas 18–34 µm and toxiform raphides 65–156 µm. Myxilla (M.) austini n. sp. has a fistulate habitus and both tornote and tylote megascleres. It appears to be tolerant of low oxygen environments. Myxilla (M.) austini n. sp. has smooth to sparsely spined styles 193–353 µm, tylotes 153–221 µm, tornotes 174–260 µm, two sizes of anchorate isochelas 13–27, 42–81 µm, and two sizes of sigmas 13–47, 33–78 µm. All specimens were collected from shallow water (intertidal to 25 m). 


1978 ◽  
Vol 35 (3) ◽  
pp. 305-314 ◽  
Author(s):  
A. G. Lewis

Nutrient and chlorophyll values were measured hourly at one of four stations on a cross-channel transect, over a 25-h period during each of 5 mo. Nitrate values increased with depth, chlorophyll decreased, and phosphate remained essentially unchanged during most months. Chlorophyll and phosphate values did not show consistent cross-channel trends, while nitrate levels were frequently higher on the southern side of the Strait. The cross-channel nitrate pattern can be at least partially explained in terms of geostrophic flow; greater amounts of nitrate-rich oceanic water enter at depth on the southern side of the Strait, while nitrate poor inshore water exists near the surface on the northern side. Key words: nutrients, chlorophyll, Juan de Fuca Strait


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