This is a classroom activity about the forcing mechanisms for the most recent cold period: the Little Ice Age (1350-1850). Students receive data about tree ring records, solar activity, and volcanic eruptions during this time period. By comparing and contrasting time intervals when tree growth was at a minimum, solar activity was low, and major volcanic eruptions occurred, they draw conclusions about possible natural causes of climate change and identify factors that may indicate climate change.

This peer-reviewed educational video explains human-caused climate change including the greenhouse effect. The role that greenhouse gases play in absorbing and re-emitting longwave radiation is illustrated. Information on how scientists know that the observed global warming is a result of human activities that burn fossil fuels is concisely explained.