ABSTRACT
This chapter explores some of the mechanisms affecting transport and mixing in lakes and reservoirs, as well as their incorporation into models of their water quality. Density stratification between the epilimnion and hypolimnion occurs because of the strong relationship between water temperature and density. The erosion due to wave action and ice formation often forms a terrace along the shores of lakes and reservoirs, the exposed portion of which is the beach. Short-wave radiation can be measured directly, using relatively inexpensive radiometers. The amount of evaporation is proportional to the water vapor pressure gradient between the water and atmosphere. Sensible heat transfer, the transport of heat due to convection and conduction is a relatively small component of the heat balance that is poorly understood. The data required to estimate surface heat exchange is often readily available from meteorological stations. Light penetration is retarded by snow and ice, affecting both the heat balance and the survival of aquatic organisms.
