Friends of the Earth: The Intergovernmental Panel on Climate Change (IPCC) releases updates on the latest climate change science . There is over 95% certainty that human influence is the dominant factor in warming since the mid 20th century. To put this into perspective – scientists are as certain that humans are warming the planet as they are that smoking causes cancer. There isn't a safe temperature rise. Each degree of warming will bring more extreme weather and sea level rises.