This short video, is the fifth in the National Academies Climate Change, Lines of Evidence series. It focuses on greenhouse gases, climate forcing (natural and human-caused), and global energy balance.

In this short video from ClimateCentral, host Jessica Harrop explains what evidence scientists have for claiming that recent global warming is caused by humans and is not just part of a natural cycle.

In this activity, students use datasets from both the Northern and Southern hemispheres to observe seasonal and hemispheric differences in changes to atmospheric C02 release and uptake over time.

In this activity, students work in groups, plotting carbon dioxide concentrations over time on overheads and estimating the rate of change over five years. Stacked together, the overheads for the whole class show an increase on carbon dioxide over five years and annual variation driven by photosynthesis. This exercise enables students to practice basic quantitative skills and understand how important sampling intervals can be when studying changes over time. A goal is to see how small sample size may give incomplete picture of data.

This activity illustrates the carbon cycle using an age-appropriate hook, and it includes thorough discussion and hands-on experimentation. Students learn about the geological (ancient) carbon cycle; they investigate the role of dinosaurs in the carbon cycle, and the eventual storage of carbon in the form of chalk. Students discover how the carbon cycle has been occurring for millions of years and is necessary for life on Earth.

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 lab exercise is designed to provide a basic understanding of a real-world scientific investigation. Learners are introduced to the concept of tropospheric ozone as an air pollutant due to human activities and burning of fossil fuels. Students analyze and visualize data to investigate this air pollution and climate change problem, determine the season in which it commonly occurs, and communicate the results.