Abstract:
A lake's vertical thermal regime has dual significance to the water quality modeller. Temperature has direct importance as it influences the rates of chemical and bio chemical reactions. However, it has additional significance as a tracer of mass transport in the water column. Infect, heat balances are a primary tool for estimating mixing rates in the vertical dimension. Temperate lakes are those with surface temperature above 4°C in winter, thermal gradients large, two circulation periods in spring and .autumn. Although other lake types can be severely polluted, discussion generally focuses on temperate lakes because many of the world's developed areas are in temperate climate and consequently many lakes in these climates are subject to pollution. The study reviews the vertical temperature variation in lakes and the mathematical models available for temperature stratification in lakes have been understood for application. Various models like Water Resources Engineers, Tennessee Valley Authority, MIT and Cornell have been reviewed.