Large-scale variations in small-scale temperature/salinity finestructure in the main thermocline of the northwest Atlantic

1976 ◽  
Vol 23 (12) ◽  
pp. 1175-1186 ◽  
Author(s):  
Terrence M. Joyce
Keyword(s):  
Large Scale ◽  
Small Scale ◽  
Northwest Atlantic ◽  
Scale Temperature ◽  
Main Thermocline

scholarly journals The Production and Dissipation of Compensated Thermohaline Variance by Mesoscale Stirring

2009 ◽  
Vol 39 (10) ◽  
pp. 2477-2501 ◽  
Author(s):  
K. Shafer Smith ◽  
Raffaele Ferrari
Keyword(s):  
Large Scale ◽  
Vertical Mixing ◽  
Small Scale ◽  
Vertical Diffusion ◽  
The North ◽  
Salinity Gradients ◽  
Scale Temperature ◽  
The Mean ◽  
Geostrophic Turbulence ◽  
Quasigeostrophic Model

Abstract Temperature–salinity profiles from the region studied in the North Atlantic Tracer Release Experiment (NATRE) show large isopycnal excursions at depths just below the thermocline. It is proposed here that these thermohaline filaments result from the mesoscale stirring of large-scale temperature and salinity gradients by geostrophic turbulence, resulting in a direct cascade of thermohaline variance to small scales. This hypothesis is investigated as follows: Measurements from NATRE are used to generate mean temperature, salinity, and shear profiles. The mean stratification and shear are used as the background state in a high-resolution horizontally homogeneous quasigeostrophic model. The mean state is baroclinically unstable, and the model produces a vigorous eddy field. Temperature and salinity are stirred laterally in each density layer by the geostrophic velocity and vertical advection is by the ageostrophic velocity. The simulated temperature–salinity diagram exhibits fluctuations at depths just below the thermocline of similar magnitude to those found in the NATRE data. It is shown that vertical diffusion is sufficient to absorb the laterally driven cascade of tracer variance through an amplification of filamentary slopes by small-scale shear. These results suggest that there is a strong coupling between vertical mixing and horizontal stirring in the ocean at scales below the deformation radius.

scholarly journals Modelling of cirrus clouds – Part 1b: Structuring cirrus clouds by dynamics

2009 ◽  
Vol 9 (2) ◽  
pp. 707-719 ◽  
Author(s):  
P. Spichtinger ◽  
K. M. Gierens
Keyword(s):  
Large Scale ◽  
Cirrus Clouds ◽  
Small Scale ◽  
Linear Processes ◽  
Microphysics Scheme ◽  
Scale Temperature ◽  
Sensitivity Studies ◽  
Cloud Evolution ◽  
Cloud Ice ◽  
The Impact

Abstract. A recently developed and validated bulk microphysics scheme for modelling cirrus clouds (Spichtinger and Gierens, 2009), implemented into the anelastic non-hydrostatic model EULAG is used for investigation of the impact of dynamics on the evolution of an arctic cirrostratus. Sensitivity studies are performed, using variation of large-scale updraughts as well as addition of small-scale temperature fluctuations and wind shear. The results show the importance of sedimentation of ice crystals on cloud evolution. Due to non-linear processes like homogeneous nucleation situations can arise where small changes in the outer parameters have large effects on the resulting cloud structure. In-cloud ice supersaturation is a common feature of all our simulations, and we show that dynamics is as least as important for its appearance than is microphysics.

scholarly journals Constraints on the mean density of the Universe which follow from the theories of adiabatic and whirl perturbations

1978 ◽  
Vol 79 ◽  
pp. 404-405
Author(s):  
A. A. Kurskov ◽  
L. M. Ozernoy
Keyword(s):  
Large Scale ◽  
Background Radiation ◽  
Small Scale ◽  
Microwave Background ◽  
Scale Temperature ◽  
Microwave Background Radiation ◽  
Initial Spectrum ◽  
Density Perturbations ◽  
The Mean ◽  
The Universe

The aim of this communication is to investigate what constraints to the cosmological parameter Ω = 2qO can be obtained if one assumes that primaeval whirl motions or adiabatic density perturbations with an appropriate initial spectrum were responsible for the formation of large scale structure in the Universe. These constraints are readily obtained from the two conditions: (i) an upper limit to small scale temperature fluctuations of the microwave background radiation, and (ii) the requirement that the primaeval perturbations should be large enough in order to produce observed structures.

scholarly journals Shark depredation rates in pelagic longline fisheries: a case study from the Northwest Atlantic

2009 ◽  
Vol 66 (4) ◽  
pp. 708-719 ◽  
Author(s):  
M. Aaron MacNeil ◽  
John K. Carlson ◽  
Lawrence R. Beerkircher
Keyword(s):  
Large Scale ◽  
Linear Models ◽  
Negative Binomial ◽  
Small Scale ◽  
Northwest Atlantic ◽  
Novel Technologies ◽  
Catch Composition ◽  
Longline Fisheries ◽  
Pelagic Longline

Abstract MacNeil, M. A., Carlson, J. K., and Beerkircher, L. R. 2009. Shark depredation rates in pelagic longline fisheries: a case study from the Northwest Atlantic. – ICES Journal of Marine Science, 66: 708–719. A suite of modelling approaches was employed to analyse shark depredation rates from the US Atlantic pelagic longline fishery. As depredation events are relatively rare, there are a large number of zeroes in pelagic longline data and conventional generalized linear models (GLMs) may be ineffective as tools for statistical inference. GLMs (Poisson and negative binomial), two-part (delta-lognormal and truncated negative binomial, T-NB), and mixture models (zero-inflated Poisson, ZIP, and zero-inflated negative binomial, ZINB) were used to understand the factors that contributed most to the occurrence of depredation events that included a small proportion of whale damage. Of the six distribution forms used, only the ZIP and T-NB models performed adequately in describing depredation data, and the T-NB and ZINB models outperformed the ZIP models in bootstrap cross-validation estimates of prediction error. Candidate T-NB and ZINB model results showed that encounter probabilities were more strongly related to large-scale covariates (space, season) and that depredation counts were correlated with small-scale characteristics of the fishery (temperature, catch composition). Moreover, there was little evidence of historical trends in depredation rates. The results show that the factors contributing to most depredation events are those already controlled by ships' captains and, beyond novel technologies to repel sharks, there may be little more to do to reduce depredation loss in the fishery within current economic and operational constraints.

scholarly journals The Response of the Water Surface Layer to Internal Turbulence and Surface Forcing

2021 ◽  
Vol 9 (2) ◽  
pp. 217 ◽  
Author(s):  
Mohammad Barzegar ◽  
Darek Bogucki ◽  
Brian K. Haus ◽  
Mingming Shao
Keyword(s):  
Surface Layer ◽  
Dissipation Rate ◽  
Water Surface ◽  
Large Scale ◽  
Large Fraction ◽  
Small Scale ◽  
Breaking Wave ◽  
Turbulent Heat ◽  
Scale Temperature ◽  
Water Surface Layer

We have carried out an experimental study of the turbulence kinetic energy dissipation rate (ϵ), temperature dissipation rate (χ), and turbulent heat flux (THF) within the water surface layer in the presence of non-breaking wave, surface convection, and horizontal heat and eddy fluxes that play a prominent role in the front. We noted that the non-breaking wave dominates ϵ values within the surface layer. While analyzing the vertical ϵ variability, the presence of a wave-affected layer from the water surface to a depth of z≈1.25λw is observed, where λw is the wavelength. ϵ associated with non-breaking waves ranged to 4.9×10−6–7×10−6 m2/s3 for the wavelength range of 0.038 m < λw < 0.098 m categorized as the gravity and gravity-capillary wave regimes. ϵ values increase for longer λw and non-breaking wave ϵ values represent their significant contribution to the ocean energy budget and dynamic of surface layer considering that the non-breaking wave covers the large fraction of ocean surface. We also found that the surface mean square slope (MSS) and wave generated ϵ have the same order of magnitude, i.e., MSS ∼ϵ. Besides, we have documented that the small-scale temperature fluctuation change (i.e., χ) is consistent with the large-scale temperature gradient change (i.e., d<T>/dz). The value of the THF is approximately constant within the surface layer. It represents that the measured THF near the water surface can be considered a surface water THF, challenging to measure directly.

Small-Scale Science to Large-Scale Profession

2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  
Large Scale ◽  
Small Scale

Development of Physics Learning Module Based on Guided Inquiry with Light Wave Material in Class XI of Senior High School

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati
Keyword(s):  
Large Scale ◽  
Learning Strategy ◽  
Student Response ◽  
Average Score ◽  
Small Scale ◽  
Design Development ◽  
Teacher Response ◽  
Student Responses ◽  
Analysis Design ◽  
Scientific Skills

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.

Planetary gentrification and urban (re)development

2019 ◽  
Vol 61 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Loretta Lees
Keyword(s):  
Low Income ◽  
Policy Making ◽  
Large Scale ◽  
Urban Redevelopment ◽  
Urban Transformation ◽  
Small Scale ◽  
Income Groups ◽  
Low Income Groups

Abstract Gentrification is no-longer, if it ever was, a small scale process of urban transformation. Gentrification globally is more often practised as large scale urban redevelopment. It is state-led or state-induced. The results are clear – the displacement and disenfranchisement of low income groups in favour of wealthier in-movers. So, why has gentrification come to dominate policy making worldwide and what can be done about it?

AGRICULTURAL PRODUCTION OF CA DONG PEOPLE IN RESETTLEMENT AREA OF TRANH RIVER HYDROPOWER NUMBER 2: CURRENT SITUATION AND IMPACT FACTORS

2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Bùi Thị Bích Lan
Keyword(s):  
Social Relations ◽  
Agricultural Production ◽  
Large Scale ◽  
Transition Process ◽  
Impact Factors ◽  
Small Scale ◽  
Scale Production ◽  
Technical Application ◽  
Production Models ◽  
Role Of The State

In Vietnam, the construction of hydropower projects has contributed significantly in the cause of industrialization and modernization of the country. The place where hydropower projects are built is mostly inhabited by ethnic minorities - communities that rely primarily on land, a very important source of livelihood security. In the context of the lack of common productive land in resettlement areas, the orientation for agricultural production is to promote indigenous knowledge combined with increasing scientific and technical application; shifting from small-scale production practices to large-scale commodity production. However, the research results of this article show that many obstacles in the transition process are being posed such as limitations on natural resources, traditional production thinking or the suitability and effectiveness of scientific - technical application models. When agricultural production does not ensure food security, a number of implications for people’s lives are increasingly evident, such as poverty, preserving cultural identity, social relations and resource protection. Since then, it has set the role of the State in researching and building appropriate agricultural production models to exploit local strengths and ensure sustainability.

Managing the impacts of mining on Ghana’s water resources from a legal perspective

2018 ◽  
Vol 1 (3) ◽  
pp. 156-165 ◽  
Author(s):  
Nasirudeen Abdul Fatawu
Keyword(s):  
Surface Water ◽  
Water Resources ◽  
Environmental Protection Agency ◽  
Large Scale ◽  
Small Scale ◽  
Mining Activities ◽  
Protection Agency ◽  
Environmental Laws ◽  
Mining Areas ◽  
Legal Perspective

Recent floods in Ghana are largely blamed on mining activities. Not only are lives lost through these floods, farms andproperties are destroyed as a result. Water resources are diverted, polluted and impounded upon by both large-scale minersand small-scale miners. Although these activities are largely blamed on behavioural attitudes that need to be changed, thereare legal dimensions that should be addressed as well. Coincidentally, a great proportion of the water resources of Ghana arewithin these mining areas thus the continual pollution of these surface water sources is a serious threat to the environmentand the development of the country as a whole. The environmental laws need to be oriented properly with adequate sanctionsto tackle the impacts mining has on water resources. The Environmental Impact Assessment (EIA) procedure needs to bestreamlined and undertaken by the Environmental Protection Agency (EPA) and not the company itself.

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