To answer the question of what is happening now and what to expect in the future, we need to travel back tens of millions of years to find out how the face of our planet was changing and what factors were influencing climate change. Right now, you're looking at a graph on the screen that shows the change in the average temperature of our planet over 500 million years. By putting together data from excavations around the world, scientists have been able to accurately determine the Earth's climate in each period. Looking at the big picture, it is easy to see the long and hot intervals were followed by shorter periods of cooling. During these periods, cold ice ages, the climate was drier, temperatures were lower, and ice caps were building up at the poles of our planet, just the way they look now.