The objective of the course of Ocean Dynamics-A (General Theory) is the knowledge of atmospheric and marine/oceanic flows at a meso- and large-scale and with and without stratification. The course aims at developing the skills needed for the development of suitable schemes and mathematical models simulating the dynamics of the oceans. In addition, the course aims at improving the knowledge of the numerical and experimental models used to simulate such flows. The course aims at defining conceptual models with different complexity levels for the simulations of atmospheric and marine/oceanic flows.
At the end of the course, the students will be able to: understand the complex dynamics of atmospheric and marine/oceanic flows occurring at different spatial scales with and without stratification; select the suitable models for the simulation of the different flows; understand and use the data obtained by laboratory and /or numerical experiments simulating stratified flows.
At the end of the course, the students will be able to: understand the complex dynamics of atmospheric and marine/oceanic flows occurring at different spatial scales with and without stratification; select the suitable models for the simulation of the different flows; understand and use the data obtained by laboratory and /or numerical experiments simulating stratified flows.
teacher profile teaching materials
- Stratification and the Brunt Vaisala frequency
- Turbulence characteristics
-Kolmogorov Theory
- The turbulent kinetic energy equation
- Turublence in the oceanic boundary layers
- Turbulence in the pycnocline : K-H instabilities
- Turbulent jets in ocean
- B. Cushman-Roisin, 1994, Introduction to Geophysical Fluid Dynamics, Prentice Hall.
Programme
- Turbulence in Ocean: an introduction- Stratification and the Brunt Vaisala frequency
- Turbulence characteristics
-Kolmogorov Theory
- The turbulent kinetic energy equation
- Turublence in the oceanic boundary layers
- Turbulence in the pycnocline : K-H instabilities
- Turbulent jets in ocean
Core Documentation
- A. Cenedese, 2006, Meccanica dei fluidi ambientale, Mc Graw-Hill.- B. Cushman-Roisin, 1994, Introduction to Geophysical Fluid Dynamics, Prentice Hall.
Reference Bibliography
- A. Cenedese, 2006, Meccanica dei fluidi ambientale, Mc Graw-Hill. - B. Cushman-Roisin, 1994, Introduction to Geophysical Fluid Dynamics, Prentice Hall.Type of delivery of the course
lessons held in classAttendance
optional attendanceType of evaluation
Exam modality The assessment is carried out through an oral examination. The interview aims to evaluate the student’s understanding of the fundamental principles of fluid mechanics for large scale applications and their ability to discuss their application to relevant physical phenomena. Questions may address both theoretical aspects and applied problems, including topics covered during lectures. Grading criteria The final grade is determined based on several factors, including: the level of knowledge and understanding of the topics; clarity of explanation; the ability to critically analyze physical phenomena; the coherence and logic of reasoning; and the correct use of technical terminology specific to the subject. teacher profile teaching materials
Viscous flows and Navier-Stokes equations, turbulent flows and Reynolds equations.
Governing equations for rotating flows
Rotating framework of reference, Unimportance of the centrifugal force, Acceleration on a three-dimensional rotating planet, Equations of Fluid Motion (Mass budget , Momentum budget, Equation of state, Energy budget, Salt and moisture budgets) Boussinesq approximation, Scales of motion, Important dimensionless numbers, Boundary conditions.
Rotation effects
Geostrophic flows and vorticity dynamics, cyclonic and anticyclonic flows, the bottom Ekman layer and the surface Ekman layer.
Ocean
Oceanic General Circulation; What drives the oceanic circulation; Large-scale ocean dynamics (Sverdrup dynamics). Western boundary currents. Thermohaline circulation; Abyssal circulation;
Atmosphere: generalities (structure and physical characteristics), definition of standard atmosphere and standard lapse rate. Atmospheric stability: dry and wet adiabatic lapse rate and atmospheric stability, conditional stability. Planetary Heat Budget.
Large scale Dynamics in atmosphere: Generalities(main sources of global scale circulation, effects of the Coriolis forces, direct and indirect cells, prevailing winds). Governing equations for large scale dynamics in atmosphere. Thermal wind relation, large-scale circulation in Hadley and Ferrel cells (theoretical analysis).
The Atmospheric Boundary Layer (ABL): generalities and definitions. Turbulent phenomena in the ABL: Mechanical and thermal turbulence, the turbulent cascade, statistical approach to turbulence in ABL (turbulence intensity and turbulent fluxes). The Turbulent kinetic equation, analysis of atmospheric stability from the vertical turbulent flux of temperature. Closure relations: local closures and K-theory, zeroth order closures based on similarity theory. Definition of the main length, time and velocity scales in ABL flows. Vertical structure of the boundary layer. Derivation of the potential temperature from the 1st law of thermodynamics. Day-night cycles of ABL in fair weather conditions. Dynamical Evolution of the ABL: entrainment zone, daily variation of the entrainment zone. Cloud-topped boundary layer overland.
Anabatic and katabatic winds. Hydrodynamic phenomena in presence of synoptic scale forcing.
Cloud physics: Generalities and definitions on cloud and rain droplets. Main Mechanisms for rain formation. Effect of curvature on condensation and evaporation (Kelvin theory). Solute effect on rain formation (Raoult's Law). Köhler theory and formation conditions for a rain droplet. Vapor deposition and early-stage growth of cloud condensation nuclei.
- B. Cushman-Roisin, 1994, Introduction to Geophysical Fluid Dynamics, Prentice Hall.
Programme
Governing equations for viscous and turbulent flowsViscous flows and Navier-Stokes equations, turbulent flows and Reynolds equations.
Governing equations for rotating flows
Rotating framework of reference, Unimportance of the centrifugal force, Acceleration on a three-dimensional rotating planet, Equations of Fluid Motion (Mass budget , Momentum budget, Equation of state, Energy budget, Salt and moisture budgets) Boussinesq approximation, Scales of motion, Important dimensionless numbers, Boundary conditions.
Rotation effects
Geostrophic flows and vorticity dynamics, cyclonic and anticyclonic flows, the bottom Ekman layer and the surface Ekman layer.
Ocean
Oceanic General Circulation; What drives the oceanic circulation; Large-scale ocean dynamics (Sverdrup dynamics). Western boundary currents. Thermohaline circulation; Abyssal circulation;
Atmosphere: generalities (structure and physical characteristics), definition of standard atmosphere and standard lapse rate. Atmospheric stability: dry and wet adiabatic lapse rate and atmospheric stability, conditional stability. Planetary Heat Budget.
Large scale Dynamics in atmosphere: Generalities(main sources of global scale circulation, effects of the Coriolis forces, direct and indirect cells, prevailing winds). Governing equations for large scale dynamics in atmosphere. Thermal wind relation, large-scale circulation in Hadley and Ferrel cells (theoretical analysis).
The Atmospheric Boundary Layer (ABL): generalities and definitions. Turbulent phenomena in the ABL: Mechanical and thermal turbulence, the turbulent cascade, statistical approach to turbulence in ABL (turbulence intensity and turbulent fluxes). The Turbulent kinetic equation, analysis of atmospheric stability from the vertical turbulent flux of temperature. Closure relations: local closures and K-theory, zeroth order closures based on similarity theory. Definition of the main length, time and velocity scales in ABL flows. Vertical structure of the boundary layer. Derivation of the potential temperature from the 1st law of thermodynamics. Day-night cycles of ABL in fair weather conditions. Dynamical Evolution of the ABL: entrainment zone, daily variation of the entrainment zone. Cloud-topped boundary layer overland.
Anabatic and katabatic winds. Hydrodynamic phenomena in presence of synoptic scale forcing.
Cloud physics: Generalities and definitions on cloud and rain droplets. Main Mechanisms for rain formation. Effect of curvature on condensation and evaporation (Kelvin theory). Solute effect on rain formation (Raoult's Law). Köhler theory and formation conditions for a rain droplet. Vapor deposition and early-stage growth of cloud condensation nuclei.
Core Documentation
- A. Cenedese, 2006, Meccanica dei fluidi ambientale, Mc Graw-Hill.- B. Cushman-Roisin, 1994, Introduction to Geophysical Fluid Dynamics, Prentice Hall.
Type of delivery of the course
LecturesType of evaluation
Oral examination, with a duration of about one hour, with questions on theory