Students explore the increase in atmospheric carbon dioxide over the past 40 years with an interactive online model. They use the model and observations to estimate present emission rates and emission growth rates. The model is then used to estimate future levels of carbon dioxide using different future emission scenarios. These different scenarios are then linked by students to climate model predictions also used by the Intergovernmental Panel on Climate Change.

This unit allows students to investigate past changes in Earth's climate. Students first explore relationships in climate data such as temperature, solar radiation, carbon dioxide, and biodiversity. They then investigate solar radiation in more depth to learn about changes over time such as seasonal shifts. Students then learn about mechanisms for exploring past changes in Earth's climate such as ice cores, tree rings, fossil records, etc. Finally, students tie all these together by considering the feedbacks throughout the Earth system and reviewing an article on a past mass extinction event.

Students use long term sea-level rise data set to create models and compare short-term trends to long-term trends. They then determine whether sea-level rise is occurring based on the data.