Rising greenhouse gas levels due to human activity are already having an impact on climate by increasing the atmospheric temperature. The current concentration of carbon dioxide released by industrial activity is the highest it has been for more than one million years. The oceans are warming and becoming more acidic. This climate change is causing radical changes to ecosystems, plants, marine life and wildlife, not to mention humans for whom agricultural resources and fresh water are becoming scarcer and coastal homes are under threat. There is still time for us to change our lifestyles.