This video succinctly explains the mechanism of the natural greenhouse effect and the cause of global climate change (anthropogenic global warming). It is short, basic, and to the point. It's also available in 12 languages!

This resource is a high quality video with a an engaging narrative discussing the need to cut carbon dioxide emissions in order to reduce the concentration in the atmosphere.

These graphs show carbon dioxide measurements at the Mauna Loa Observatory, Hawaii. The graphs display recent measurements as well as historical long term measurements. The related website summarizes in graphs the recent monthly CO2, the full CO2 Record, the annual Mean CO2 Growth Rate, and gives links to detailed CO2 data for this location, which is one of the most important CO2 tracking sites in the world.