Thermal response of demersal and pelagic juvenile fishes from the surf zone during a heat‐wave simulation

A subgrid scale model is presented for the large-wave simulation (LWS) of spilling breaking waves over bottom of arbitrary shape and finite depth. According to LWS formulation, large velocity and free-surface scales are fully resolved, while subgrid scales are accounted for by an eddy viscosity model, similar to large-eddy simulation (LES). The LWS-based model is applied on the two-dimensional wave propagation over a constant-slope bed. Fluid motion is described by the Euler equations for inviscid but rotational flow, subject to the fully non-linear free-surface boundary conditions. The application of LWS is facilitated by a boundary-fitted transformation, which introduces free-surface elevation terms in the Euler equations and simplifies the numerical implementation. Subgrid velocity scales are modeled similarly to LES, while the effect of free-surface subgrid scales are modeled by wave SGS stresses model. The resulting equations are solved numerically by a two-stage fractional time-step scheme, while an absorption zone is placed in the outflow region to minimize reflection by the outgoing waves. The simulation is carried out for the propagation and breaking of waves over a flat bed with constant slope 1/35 and results are compared to available experimental data. The numerical predictions for the breaking height, the breaking depth and the free-surface elevation dissipation in the surf zone agree very well with the corresponding measurements. The model predicts the vorticity generation in the breaking face of the wave and the appearance of the undertow current in the surf zone. The predicted shear of the undertow current is higher than the measured one.

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Microcalorimeters for X-Ray Spectroscopy

International Astronomical Union Colloquium ◽

10.1017/s0252921100107365 ◽

1988 ◽

Vol 102 ◽

pp. 41

Author(s):

E. Silver ◽

C. Hailey ◽

S. Labov ◽

N. Madden ◽

D. Landis ◽

...

Keyword(s):

High Resolution ◽

High Efficiency ◽

Thermal Response ◽

Low Noise ◽

High Resolution Spectroscopy ◽

Superconducting Transition ◽

Sapphire Substrates ◽

Laboratory Plasmas ◽

Adiabatic Demagnetization ◽

Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

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A Quasi-3D Surf Zone Model

Coastal Engineering 1994 ◽

10.1061/9780784400890.165 ◽

1995 ◽

Author(s):

Jung Lyul Lee ◽

Hsiang Wang

Keyword(s):

Surf Zone ◽

Zone Model

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Nonlinear Wave Dynamics in the Surf Zone

Coastal Engineering 1996 ◽

10.1061/9780784402429.092 ◽

1997 ◽

Author(s):

O. R. Sørensen ◽

P. A. Madsen ◽

H. A. Schäffer

Keyword(s):

Nonlinear Wave ◽

Surf Zone ◽

Wave Dynamics

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Mixing of Heated Water Discharged in the Surf Zone

Coastal Engineering 1978 ◽

10.1061/9780872621909.157 ◽

1978 ◽

Cited By ~ 3

Author(s):

Kiyoshi Horikawa ◽

Ming-Chung Lin ◽

Tamio O. Sasaki

Keyword(s):

Surf Zone ◽

Heated Water

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Numerical simulation of the tree higro-thermal response in forest fire environment

WEENTECH Proceedings in Energy ◽

10.32438/wpe.0220 ◽

2020 ◽

pp. 57-65

Author(s):

Eusébio Conceiçã ◽

João Gomes ◽

Maria Manuela Lúcio ◽

Jorge Raposo ◽

Domingos Xavier Viegas ◽

...

Keyword(s):

Forest Fire ◽

Numerical Study ◽

Thermal Response ◽

View Factor ◽

Tree Model ◽

Pine Tree ◽

Surface Temperatures ◽

Fire Environment ◽

Fire Front ◽

Heat Exchanges

This paper refers to a numerical study of the hypo-thermal behaviour of a pine tree in a forest fire environment. The pine tree thermal response numerical model is based on energy balance integral equations for the tree elements and mass balance integral equation for the water in the tree. The simulation performed considers the heat conduction through the tree elements, heat exchanges by convection between the external tree surfaces and the environment, heat exchanges by radiation between the flame and the external tree surfaces and water heat loss by evaporation from the tree to the environment. The virtual three-dimensional tree model has a height of 7.5 m and is constituted by 8863 cylindrical elements representative of its trunks, branches and leaves. The fire front has 10 m long and a 2 m high. The study was conducted taking into account that the pine tree is located 5, 10 or 15 m from the fire front. For these three analyzed distances, the numerical results obtained regarding to the distribution of the view factors, mean radiant temperature and surface temperatures of the pine tree are presented. As main conclusion, it can be stated that the values of the view factor, MRT and surface temperatures of the pine tree decrease with increasing distance from the pine tree in front of fire.

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Heat wave effects on biomass and vegetative growth of macrophytes after long-term adaptation to different temperatures: a mesocosm study

Climate Research ◽

10.3354/cr01352 ◽

2015 ◽

Vol 66 (3) ◽

pp. 265-274 ◽

Cited By ~ 16

Author(s):

Y Cao ◽

ÉM Neif ◽

W Li ◽

J Coppens ◽

N Filiz ◽

...

Keyword(s):

Heat Wave ◽

Vegetative Growth ◽

Wave Effects ◽

Different Temperatures

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Prey tell: what quillback rockfish early life history traits reveal about their survival in encounters with juvenile coho salmon

Marine Ecology Progress Series ◽

10.3354/meps13300 ◽

2020 ◽

Vol 650 ◽

pp. 7-18 ◽

Cited By ~ 1

Author(s):

HW Fennie ◽

S Sponaugle ◽

EA Daly ◽

RD Brodeur

Keyword(s):

Life History ◽

Early Life ◽

Life History Traits ◽

Direct Evidence ◽

Coho Salmon ◽

Larval Fish ◽

Early Life History ◽

In The Wild ◽

Otolith Microstructure Analysis ◽

Pelagic Juvenile

Predation is a major source of mortality in the early life stages of fishes and a driving force in shaping fish populations. Theoretical, modeling, and laboratory studies have generated hypotheses that larval fish size, age, growth rate, and development rate affect their susceptibility to predation. Empirical data on predator selection in the wild are challenging to obtain, and most selective mortality studies must repeatedly sample populations of survivors to indirectly examine survivorship. While valuable on a population scale, these approaches can obscure selection by particular predators. In May 2018, along the coast of Washington, USA, we simultaneously collected juvenile quillback rockfish Sebastes maliger from both the environment and the stomachs of juvenile coho salmon Oncorhynchus kisutch. We used otolith microstructure analysis to examine whether juvenile coho salmon were age-, size-, and/or growth-selective predators of juvenile quillback rockfish. Our results indicate that juvenile rockfish consumed by salmon were significantly smaller, slower growing at capture, and younger than surviving (unconsumed) juvenile rockfish, providing direct evidence that juvenile coho salmon are selective predators on juvenile quillback rockfish. These differences in early life history traits between consumed and surviving rockfish are related to timing of parturition and the environmental conditions larval rockfish experienced, suggesting that maternal effects may substantially influence survival at this stage. Our results demonstrate that variability in timing of parturition and sea surface temperature leads to tradeoffs in early life history traits between growth in the larval stage and survival when encountering predators in the pelagic juvenile stage.

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