Mapping Physical Characteristics of the Columbia River Mouth Using Transmittered Diving Waterbirds

2013 ◽  
Author(s):  
Daniel D. Roby ◽  
Donald E. Lyons ◽  
Adam Peck-Richardson ◽  
James A. Lerczak
Keyword(s):  
River Mouth ◽  
Columbia River ◽  
Physical Characteristics

Field and Numerical Study of the Columbia River Mouth

2013 ◽  
Author(s):  
Guy Gelfenbaum ◽  
Jamie MacMahan ◽  
Ad Reniers
Keyword(s):  
Numerical Study ◽  
River Mouth ◽  
Columbia River

scholarly journals FORECASTING THE WAVE-CURRENT INTERACTIONS AT THE MOUTH OF THE COLUMBIA RIVER, OR, USA

2012 ◽  
Vol 1 (33) ◽  
pp. 53 ◽  
Author(s):  
Sarah Kassem ◽  
H. Tuba Ozkan-Haller
Keyword(s):  
Pacific Northwest ◽  
Mean Squared Error ◽  
River Mouth ◽  
Columbia River ◽  
Tidal Currents ◽  
General Effect ◽  
The Pacific ◽  
Wave Forecast ◽  
Channel Wave ◽  
Wave Heights

An operational wave forecast of the area near the mouth of the Columbia River is presented. This region is known for its large waves and strong tidal currents. The forecast is forced with full directional spectra obtained from a refined WaveWatchIII forecast of the Pacific Northwest, and tidal current inputs are obtained from an estuarine circulation forecast of the Columbia River. The forecast has been operational since August 2011 providing short-term predictive wave information at the mouth of the Columbia River. Results from a 6-month period are promising, with a normalized root-mean-squared error (NRMSE) of 16% at the location of an inshore buoy, which is located outside the zone of tidal influence in 25 m water depth. Near the river mouth and in the channel, wave heights are heavily dominated by the tidal currents which significantly increase wave heights on ebb tides. Hindcast results shows that the model is able to predict the general effect of the tidal currents with a NRMSE of 30% in wave heights at the river mouth. Despite some of the model limitations, it still provides valuable information to navigators and bar pilots since it includes the effects of the tidal currents.

Bathymetric Distribution of Brittlestars (Ophiuroidea) Collected off the Northern Oregon Coast

1965 ◽  
Vol 22 (6) ◽  
pp. 1407-1424 ◽  
Author(s):  
Sergei Astrahantseff ◽  
Miles S. Alton
Keyword(s):  
Atomic Energy Commission ◽  
River Mouth ◽  
Benthic Fauna ◽  
Columbia River ◽  
Single Species ◽  
Species Number ◽  
Bathymetric Distribution ◽  
Number Of Species ◽  
Study Species ◽  
Benthic Zone

A cooperative study by the Bureau of Commercial Fisheries and the U. S. Atomic Energy Commission was undertaken to evaluate the composition of benthic fauna indigenous to waters adjacent to the Columbia River mouth. Standard stations were established by 25-fath intervals between 50 and 500 fath, and by 50-fath intervals from 500 to 1050 fath. Fifty- to 500-fath stations were monitored seasonally while sampling of deeper stations was generally restricted to spring and summer cruises.Twenty-four species of ophiuroids representing eight families and 14 genera were collected during this study. Species number varied by station ranging from one at 650 fath to a maximum of nine species at 300 fath.The number of species of ophiuroids by benthic zone showed a general increase with increasing depth. The total number of species collected by benthic zone was 4 from the sublittoral, 8 from the upper bathyal, 13 from the lower bathyal, and 15 from the abyssal. One, three, and eight species were confined to the outer sublittoral, lower bathyal, and abyssal, respectively.The highest availability of ophiuroids occurred between 150 and 250 fath and between 800 and 1050 fath. Lowest availability occurred at 125, 325, and 350 fath where few or no ophiuroids were observed. Larger catches of ophiuroids were estimated to contain from 500 to 2000 individuals. A single species, Ophiura sarsii, consistently dominated catches from 150 to 250 fath; while four species, Ophiocten pacificum, Ophiolimna bairdi, Ophiomusium lymani, and Ophiophthalmus normani, dominated catches between 800 and 1050 fath.The families Ophiuridae and Ophiacanthidae predominate in the study area. Together, they account for the majority of species collected which include the five most abundant species.The bathymetric distribution of ophiuroids from the Columbia River trackline illustrates a changing species composition with increasing depth, with the existence of both stenobathic and eurybathic species.

scholarly journals Tsunami Hydrodynamics in the Columbia River

2012 ◽  
Vol 7 (5) ◽  
pp. 604-608 ◽  
Author(s):  
Harry Yeh ◽  
◽  
Elena Tolkova ◽  
David Jay ◽  
Stefan Talke ◽  
...  
Keyword(s):  
Pacific Northwest ◽  
River Estuary ◽  
River Mouth ◽  
Columbia River ◽  
The United States ◽  
Large River ◽  
Cascadia Subduction Zone ◽  
The Pacific ◽  
The 2010 Chile Tsunami ◽  
Tohoku Tsunami

On 11 March 2011, the Tohoku Tsunami overtopped a weir and penetrated 49 km up the Kitakami River, the fourth largest river in Japan [1]. Similarly, the 2010 Chile tsunami propagated at least 15 km up the Maule River [2]. In the Pacific Northwest of the United States, large tsunamis have occurred along the Cascadia subduction zone, most recently the ‘orphan tsunami’ of 1700 (Atwater et al. [3]). The expected future occurrence of a Cascadia tsunami and its penetration into the Lower Columbia River became the subject of “the Workshop on Tsunami Hydrodynamics in a Large River” held in Corvallis, Oregon, 2011. We found that tsunami penetration into the Columbia River is quite different from a typical river. The tsunami enters the vast river estuary through the relatively narrow river mouth of the Columbia, which damps and diffuses its energy. The tsunami transforms into a long period, small amplitude wave that advances to Portland, 173 km from the ocean. Understanding this unique tsunami behavior is important for preparing a forthcoming Cascadia tsunami event.

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