AMCE6081 General Description Physical and biological processes are inter-related aspects that govern the productivity of marine ecosystems. Provides an introduction to the physical processes that control abundance of marine organisms in the ocean. Turbulence in surface and bottom boundary layers and its roles on the lives of plants and animals; buoyancy- and wind-induced circulation, mixing, coastal upwelling/ downwelling processes, fronts, river plume, tides, internal waves, circulation and eddy and their effects on biological transport, primary production; zooplankton, fish and the regeneration of nutrients; NPZD (Nutrient, Phytoplankton, Zooplankton and Detritus) chemical-biological model; mathematical and numerical techniques in the of coupled hydrodynamic- ecosystem model.

AMCE6082

3 Global distribution of chlorophyll averaged over the period from 1 January 2002 to 28 February 2005 using data collected from MODIS on the Aqua satellite. Chlorophyll values range from 0.01 mg/m3 (purple) to 60 mg/m3 (red). From NASA Goddard Space Flight Center.Chlorophyll values

AMCE6084 Xie, L. and W.W. Hsieh, 1995

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7 Sun Food Web Photosynthesis by phytoplankton Passed from organism to organism by feeding transfers Currents, tides (also moon), turbulence and stratification by heating or associated wind * * 1.Alters boundary layers, stratification and euphotic layer, causes retention of planktonic organisms and modifies light penetration. 2. Transports nutrients and waste products, assists migrations, affects the rate of encounter between planktonic predators and their prey. 3. Rate of biological process is affected by T (C) and organisms colonizing is determined by v (m/s).

AMCE6088 Multi temporal and spatial scales in physic and biologic processes

AMCE6089 OSU 1mm=10 -3 m

AMCE60810 Transfers of nutrients and waste products by molecular diffusion Transfers of nutrients and waste products by faster turbulent diffusion, mesoscale, upwelling, eddy, front, surface and internal waves Internal Rossby deformation radius= h: water depth; ρ: water density; Ω: angular velocity of earth rotation; Φ: latitute (m) Transfers of nutrients and waste products by eddy turbulent diffusion,ba sin scale circulation, plantary waves, tides Molecular

AMCE60811 About 100 yrs 1-10 yrs days-1wks days hoursTime scale Large marine mammal Temporal scales determined from organisms Increase fluctuations in number Process of trophic transfer Molecular

AMCE60812 Turbulence, diffusion and boundary layers, mixing, mixed layer

AMCE60813 slowly varying mean fields rapidly varying turbulent component Periods of u’: from a second (minimum) to tens minutes (maximum). Size of u’ : from a few millimeters (µm) (minimum) to a few meters (maximum) Periods

AMCE60814 Laminar Flow and Turbulent Flow The terms laminar flow and purely viscous (molecular) flow are used synonymously to mean a fluid flow which flows in laminas or layers, as opposed to turbulent flow in which the velocity components have random turbulent fluctuations imposed upon their mean values. In general, increase the flow will change from laminar to turbulent. The effect of viscosity are still present in turbulent flow, but they are masked by much strong turbulence. The viscosity due to turbulent flow is sometimes called as turbulent viscosity.

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AMCE60816 Sources of turbulent energy: 1: Instability induced by surface or internal wave breakings, 2: Wind stirring at the sea surface, 3. Velocity shear, 4. Strong currents, meanders and eddies breakings. Velocity shear

AMCE60817

AMCE60818 Definitions: Viscosity, Friction and Ideal Flow Molecular Viscosity: internal friction of fluid due to molecular motion, which causes it resist the tendency to flow. This comes to work when the scale of turbulence is < 1mm. Viscous force, i.e. friction depends on the type of fluid and physical configuration or flow pattern (including both molecular and turbulent viscous force. The magnitude of latter is much larger). If the viscous force is negligible, the flow is defined as ideal flow or inviscid flow in which friction is precisely zero. A fluid with very small viscosity may behave quite differently to a (hypothetical) fluid with no viscosity at all.

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AMCE60820 Reynolds number u: velocity, d: typical dimension, : viscosity coefficients

AMCE60821 Table 2.1

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AMCE60823 Diffusion-Viscosity Diffusion: mixing of a property by the random motions of molecules (molecular diffusion) or of eddy (turbulent or eddy diffusion). Viscosity: it is resistance force of the water, acts to resist the velocity. Its consequence is corresponding to the associated diffusion.

AMCE60824 Some Estimations Fick’s Law: to estimate the flux and time scale of a variable due to molecular diffusion The length scale to diffuse Coefficient of molecular diffusion=1.5x10 -9 m 2 s -1 Kolmogoroff Length: length scale across the smallest eddy of smallest fluctuation. L=(kinematic viscosity (molecular)/turbulent-energy dissipation) 1/4 Largest turbulent eddies: to determine the vertical excursion of the small passive organisms being moved about by the turbulent flow Lb=(turbulent energy dissipation/stratification

AMCE60825 (Bottom) Boundary Layer Solid boundary in which water movement is reduced. It reduces the exchange rate of molecules of O2, CO2, NH3 etc. with the ambient waters.

AMCE60826 No-slip boundary or u=0 at solid surface Idealized case Real case