Consequences of fluctuations in the ambient air temperature at Lake Tanganyika --- A wavelet analysis

We study the fluctuations of the horizontal wind speed and of both the ambient air temperature and the water temperature according to the depth. Our study clearly shows how Lake Tanganyika is thermally stratified, showing four different water layers. The study shows how waters of upper layers tend to have the same temperature as the deepest water during the dry season. The water stratification tends then to disappear completely in the dry season. The study is based on the fact that water releases energy to heat the ambient air during the dry season and absorbs heat energy during the rainy season. We analyzed the behavior of the Richardson number in order to better understand the mode of transmission of the exchanged energy between water and ambient air. Fourier and wavelet analyses show that fluctuations in the ambient air temperature should play a major role in the behavior of water and of wind and probably of many other physical processes occurring in the site of Lake Tanganyika. This work shows the existence of a very large heat reservoir that consists of the great mass of waters of the hypolimnion and of another great heat source at variable temperature that consists of the large mass of atmospheric air surrounding the lake. The heat reservoir with variable temperature, namely the atmospheric ambient air, should ultimately determine the behavior of Lake Tanganyika