The author describes how the topic of climate change has uncertainty associated with similar to many other scientific topics, but the public’s perception of climate change is that they feel they understand it better than they actually do. Thus, there are challenges in communicating climate science to the broader community. First, there are issues of language. This is seen in the IPCC working group reports. Terms such as “likelihood” cause readers to interpret more than what they intend by also incorporate a measure of consequence. Therefore, the perceived risk of a low probability high consequence event is higher than intended. There is also an importance in distinguishing between uncertainties in observations and in model results. The main lesson learned is that the complexity of climate change requires separate assessments for the changes in frequency for the probability of damaging events and the magnitude of damage that may occur. This reference is useful for identifying how IPCC language is perceived by their audiences and has a good recommendation for treating the definition of uncertainty in future assessments.