scholarly journals Inner‐Shelf Vertical and Alongshore temperature Variability in the Subtidal, Diurnal, and Semidiurnal Bands Along the central California coastline with headlands

2020 ◽  
Vol 125 (3) ◽  
Author(s):  
Falk Feddersen ◽  
Jamie H. MacMahan ◽  
Thomas M. Freismuth ◽  
Matt K. Gough ◽  
Michael Kovatch
Keyword(s):  
Temperature Variability ◽  
Inner Shelf ◽  
Central California

scholarly journals Alongshore Variability of Shoaling Internal Bores on the Inner Shelf

2020 ◽  
Vol 50 (10) ◽  
pp. 2965-2981
Author(s):  
Jacqueline M. McSweeney ◽  
James A. Lerczak ◽  
John A. Barth ◽  
Johannes Becherer ◽  
Jennifer A. MacKinnon ◽  
...  
Keyword(s):  
Kinetic Energy ◽  
Spatiotemporal Patterns ◽  
Velocity Measurements ◽  
Inner Shelf ◽  
Length Scales ◽  
Central California ◽  
Internal Bores ◽  
Internal Bore ◽  
Water Depths

AbstractTemperature and velocity measurements from 42 moorings were used to investigate the alongshore variability of nonlinear internal bores as they propagated across the central California inner shelf. Moorings were deployed September–October 2017 offshore of the Point Sal headland. Regional coverage was ~30 km alongshore and ~15 km across shore, spanning 9–100-m water depths. In addition to subtidal processes modulating regional stratification, internal bores generated complex spatiotemporal patterns of stratification variability. Internal bores were alongshore continuous on the order of tens of kilometers at the 50-m isobath, but the length scales of frontal continuity decreased to O(1 km) at the 25-m isobath. The depth-averaged, bandpass-filtered (from 3 min to 16 h) internal bore kinetic energy was found to be nonuniform along a bore front, even in the case of an alongshore-continuous bore. The pattern of along-bore variability varied for each bore, but a 2-week average indicated that was generally strongest around Point Sal. The stratification ahead of a bore influenced both the bore’s amplitude and cross-shore evolution. The data suggest that alongshore stratification gradients can cause a bore to evolve differently at various alongshore locations. Three potential bore fates were observed: 1) bores transiting intact to the 9-m isobath, 2) bores being overrun by faster, subsequent bores, leading to bore-merging events, and 3) bores disappearing when the upstream pycnocline was near or below middepth. Maps of hourly stratification at each mooring and the estimated position of sequential bores demonstrated that an individual internal bore can significantly impact the waveguide of the subsequent bore.

Effects of marine reserves on predator-prey interactions in central California kelp forests

2020 ◽  
Vol 655 ◽  
pp. 139-155
Author(s):  
DC Yates ◽  
SI Lonhart ◽  
SL Hamilton
Keyword(s):  
Species Interactions ◽  
Size Structure ◽  
Marine Reserves ◽  
Mortality Rates ◽  
Kelp Forests ◽  
Negative Effects ◽  
Central California ◽  
Invertebrate Predators ◽  
Predatory Fishes ◽  
Density And Biomass

Marine reserves are often designed to increase density, biomass, size structure, and biodiversity by prohibiting extractive activities. However, the recovery of predators following the establishment of marine reserves and the consequent cessation of fishing may have indirect negative effects on prey populations by increasing prey mortality. We coupled field surveys with empirical predation assays (i.e. tethering experiments) inside and outside of 3 no-take marine reserves in kelp forests along the central California coast to quantify the strength of interactions between predatory fishes and their crustacean prey. Results indicated elevated densities and biomass of invertebrate predators inside marine reserves compared to nearby fished sites, but no significant differences in prey densities. The increased abundance of predators inside marine reserves translated to a significant increase in mortality of 2 species of decapod crustaceans, the dock shrimp Pandalus danae and the cryptic kelp crab Pugettia richii, in tethering experiments. Shrimp mortality rates were 4.6 times greater, while crab mortality rates were 7 times greater inside reserves. For both prey species, the time to 50% mortality was negatively associated with the density and biomass of invertebrate predators (i.e. higher mortality rates where predators were more abundant). Video analyses indicated that macro-invertivore fishes arrived 2 times faster to tethering arrays at sites inside marine reserves and began attacking tethered prey more rapidly. The results indicate that marine reserves can have direct and indirect effects on predators and their prey, respectively, and highlight the importance of considering species interactions in making management decisions.

PERFORMANCE METRICS AND TEMPERATURE VARIABILITY IN A 16 NM SPACER FINFET

2018 ◽  
Vol 8 (4) ◽  
pp. 41
Author(s):  
SANGEETA MANGESH ◽  
KRISHAN K. SAINI ◽  
CHOPRA P. K. ◽  
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...  
Keyword(s):  
Performance Metrics ◽  
Temperature Variability
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