The American Chemical Society are producing some wonderful bite-size videos in a series called Bytesize Science (see what they did there!). They are, of course mostly about chemistry, and feature some cool stuff on the science of alcohol, and why orange juice tastes so bad after brushing your teeth (or eating shampoo). They don’t cover much geochemistry unfortunately, but there are a couple of earth monitoring videos. This one, on NASA’s Aura satellite covers how we keep tabs on air pollutants such as Ozone. Well worth 7 and a half minutes of your time!