The above image on the CO2 implications of the volcanic eruption is from InformationIsBeautiful. It comes via Fallows, our in-house aviation maven, who is all over the volcanic ash story. Here's his FAQ on ash and airplanes. Tyler Cowen flags an article claiming that air freight "is responsible for a quarter of the value of all goods moved into and out of the UK". And Yglesias asks the important question: how to pronounce "Eyjafjallajökull." He links to audio of the name being spoken but it isn't much help. John Conway has a solution:

Okay, I have tried, but pronouncing this one eludes me…I think it needs a new name. (Simply “Kull” might do.)