Students examine data from Mauna Loa to learn about CO2 in the atmosphere. The students also examine how atmospheric CO2 changes through the seasonal cycle, by location on Earth, and over about 40 years and more specifically over 15 years. Students graph data in both the Northern and Southern Hemisphere and draw conclusions about hemispherical differences in CO2 release and uptake.

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.

This video segment from 'Earth: The Operators' Manual' explores how we know that today's increased levels of CO2 are caused by humans burning fossil fuels and not by some natural process, such as volcanic out-gassing. Climate scientist Richard Alley provides a detailed step-by-step explanation that examines the physics and chemistry of different "flavors" or isotopes of carbon in Earth's atmosphere.

This is a laboratory activity in which students will compare the amount of carbon dioxide in four different sources of gas and determine the carbon dioxide contribution from automobiles. They test ambient air, human exhalation, automobile exhaust, and nearly pure carbon dioxide from a vinegar/baking soda mixture.

This short video describes the Hestia project - a software tool and data model that provide visualizations of localized CO2 emissions from residential, commercial, and vehicle levels, as well as day versus night comparisons, in the city of Indianapolis.

This NASA video discusses the impacts of the sun's energy, Earth's reflectance and greenhouse gases on the Earth System.

Two short, narrated animations about carbon dioxide and Earth's temperature are presented on this webpage. The first animation shows the rise in atmospheric CO2 levels, human carbon emissions, and global temperature rise of the past 1,000 years; the second shows changes in the level of CO2 from 800,000 years ago to the present.