A high short and middle term variability overshadows longer term trends. They may well be consequences of weather and climate changes rather than their causes.

• winds and air mass flows that transport energy and water, mostly from tropical areas to higher latitudes;
• cloud formation and rainfalls that follow water evaporation, essential to provide soil moisture and the ability to develop flora and fauna;
• tropical cyclones and tornadoes;
• ocean currents and thermal oscillations, taking place over decades or longer time periods, and interfering with the atmosphere;
• ice formation and melting;
• sea level change;