Earth,Atmospheric, Ocean & Planetary Sciences Paper 2 Oceanography
(i) Physical Oceanography: Equation of State of seawater, current system including under current, their formation and theories, oceanic fronts.
Subtropical current system - Western and Eastern boundary currents Somali current thermohaline and abyssal circulation; formation of water masses mixing and double diffusion.
TSV diagrams; computation of divergence and estimation of vertical velocity; acoustics and optics.
(ii) Dynamical Oceanography: Equations of motion of frictionless ocean currents; scale analysis; barotropic and baroclinic approximation; geostrophic currents in a stratified ocean, the 2- layer approximation, and White-Margules equation; gradient currents and mass stratification; relative currents and slope currents; Ekman’s theory, Sverdrup, Stommel and Munk’s theories; Upwelling and sinking with special reference to the Indian ocean.
(iii) Ocean Waves and Tides: Small amplitude ocean waves; wave celerity; wave energy and group velocity. Finite amplitude waves, long waves and internal wave; wind waves, their origin, growth, propagation and decay; significant wave height and period. Waves spectrum, Principles of wave forecasting SMB and PNJ methods; tides, their causes, variation and types; tidal currents; harmonic analysis, finite difference method and prediction of tides.
(iv) Air-Sea Interaction: Laminar and turbulent flows; Reynolds stresses; Richardson’s criterion for turbulence; principles of Prandtl’s mixing length theory; Taylor’s statistical theory and Kolmogoroffs similarity theory; Air Sea interaction at various scales; planetary and laminar boundary layer, surface layer and spiral layer; Sea surface as a lower boundary of air-flow, and its geometry; wind field in the first few meters of the sea surface, wind structure in the maritime frictional layer; transfer of heat and water vapour, determination of air-sea fluxes; energy exchange and global heat and water budgets, convection and its role in tropical circulations, effects of upwelling and sinking on the ocean-atmosphere system.
(v) Coastal and Estuarine Oceanography: Factors influencing coastal processes; transformation of waves in shallow water; Effects of stratification; effect of bottom friction, phenomena of wave reflection, refraction and diffraction; breakers and surf; littoral currents; wave action on sediments - movement to beach material; rip currents; beach stability ocean beach nourishment; harbour resonance; seiches; Tsunamis; Interaction of waves and structure. Sea Walls, groynes, revetments, etc. Estuaries: classification and nomenclature; tides in estuaries; estuarine circulation and mixing; depth - averaged and breadth - averaged models; sedimentation in estuaries; salinity intrusion in estuaries; Effect of stratification; coastal pollution; mixing and diffusion dispersal of pollutants in estuaries and nearshore areas; standing concentration; coastal zone management.
(vi) Chemical Oceanography: Major and minor constituents of sea- water and their residence times; processes controlling the composition of sea-water; Dissolved gases in sea-water; their sources and sinks. Carbondioxide system, distribution of alkalinity; Physical chemistry of seawater; dynamic equilibrium in chemical composition of the ocean including trace metals, organic materials. Biogeochemical cycling and its effect on atmospheric composition and climate. Inter-relationships between ocean circulation, primary productivity and chemical composition of the atmosphere and ocean.
Stable and radioactive isotopes; chemistry of interstitial waters and transfer of solutes across the sediment- water interface; marine pollution, pathways of transfer of various pollutants (petroleum hydrocarbons, pesticides, trace metals etc.) and their fates in the sea.
Chemistry of marine natural products; biomedical potential of marine biota: remote sensing of the oceans.
(ii) Marine Geology: Morphological and tectonic domains of the ocean floor. Mid-oceanic ridge systems, hydrothermal vents and sea-water basalt interaction; modes and rates of sedimentation in the oceans; diagenetic changes in oxic and anoxic environments, mobility of redoxmetals; nature of deep sea sediments and processes and regulating sedimentary composition; geochronology of marine sediments, sedimentary markers (biological and chemical) of paleoenvironmental conditions. Mineral resources of the ocean - phosphorites, manganese and other deposits and the factors controlling their distribution.
