Human: Is there any evidence to support the idea that humans have caused global warming? Assistant: 
Yes, there is a lot of evidence supporting the idea that human activity has contributed to global warming. The Intergovernmental Panel on Climate Change (IPCC) released its Fourth Assessment Report in 2007 and concluded that "human activities are the dominant cause of the observed warming since the mid-20th century." Other research has shown that greenhouse gas emissions from burning fossil fuels, deforestation, and other human activities have led to an increase in global temperatures.