Oceanography (2+1)

Absorption of radiation, eddy conductivity, diffusivity and viscosity

Viscosity of sea water

The viscosity of seawater has an important influence on the motions of the world ocean and upon the nature of the forms of life that float or swim in the sea.

Viscosity arises from the internal friction of a fluid and may be defined as internal resistance to flow.  It represents the ease with which molecules in the fluid move past one another or, alternatively, It also repreents the ease with which mechanical energy can be exchanged between adjacent molecules.  It is fluid viscosity that causes a motorboat to stop when the engine has been stopped.  The viscosity of a fluid depends upon the chemical nature of its molecules.  Viscosity is greatly affected by the temperature of the fluid; the viscosity of a fluid doubles if the temperature is decreased by 20⁰c.  Salinity has only a minor effect on viscosity.  In fact, the viscosity of seawater is about the same as that of fresh water at the same temperature.

Diffusion or diffusivity

       It refers to  transfer of material (eg. Salt) and temperature by eddies  diffusion causes spreading or scattering of matter under the influence of a concentration gradient with movement from the stronger to weaker solution.