This PBS video shows how Klaus Lackner, a geophysicist at Columbia University, is trying to tackle the problem of rising atmospheric CO2 levels by using an idea inspired by his daughter's 8th-grade science fair project. The video examines the idea of pulling CO2 out of the atmosphere via a passive chemical process.

This static graph of changes in CO2 concentrations goes back 400,000 years, showing the dramatic spike in recent years.