A theory for the cause of climate change is developed based on measurements of glaciation, and of atmosphere temperature and CO2 concentration, with some data going back almost two million years. Previously accepted theory is that the Earth's attitude in space with respect to the Sun, Moon and other planets is what has caused climate cycles in the past. It is found in the present analysis that normal climate control was disrupted as continents moved to their present location. The system went into oscillation and the main influence on climate since then has been the ocean temperature acting opposite to that of the rest of the environment with a lag time of about 12,000years. When the ocean is colder skies are clear and there is CO2 buildup in the atmosphere. When the ocean is warmer skies are cloudy and CO2 is reabsorbed into the ocean. As well as solving the mystery of the Ice Age ending, predictions for future change can be made using theory related to these findings.