Deeper mixing depths often occur in tropical lakes compared to their temperate
counterparts, partly due to the narrow ranges of temperature and smaller absolute
gradients that occur (Kling et al. 1988). Decreased water viscosity at higher temperatures,
reduced Coriolis effect, intensity of storms and high maximum wind speeds also play a
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role. The 1oC temperature difference between the top and bottom of Lake Challa in
September is likely enough to contribute to the stratification of the water column. Smaller
temperature difference between the top and the bottom of the water column are sufficient
to maintain stratification at the equator due to the large changes in water density at higher
temperatures.