Climate change is a reality. Today, our world is hotter than it has been in two thousand years. By the end of the century, if current trends continue, the global temperature will likely climb higher than at any time in the past two million years.

The Earth's atmosphere is made up of a blanket of gases, which trap enough heat to sustain life. However, by burning fossil fuels and cutting down forests humans pump billions of tonnes of carbon dioxide (CO2) into the atmosphere. We also add...

Carbon dioxide and fossil fuels: where do the greenhouse gases come from, who put them in the atmosphere and what can we do about it?