Investigation of periodical astronomical effects on hydroclimatic phenomena

In this thesis we search the possibility that astronomical periods have effect to the hydroclimate of Earth. We investigate the movement of Moon both alone and in the system Moon-Earth-Sun and find relative periods that can potentially affect the hydroclimate through tidal forcing. We then investigate the movement of Jupiter, Earth, Venus, Mercury (that bring the greatest tidal forcing to Sun) around the Sun and find relative periods of synods. The Northern Hemisphere temperatures of Jones et al. (1998) reveal well establishment for our two cosine models with periods 244.6 (quasi-periodic) or 265.4 (mean periodic) years of the synod of Jupiter, Earth, Venus, Mercury and 251 years of the seasonality of the synods of Earth with Venus. Moreover the 251 year constituent of the model with periods 244.6 and 251 years describes well the highs and lows of river Nile for the last 1200 years, as does the 265.4 constituent of the model with periods 265.4 and 251 years. We refer to the possibility that the 100,000 year Milankovic cycle is so strong because of tidal effect.