I initially assumed that the reason volcanic ash was shutting down European air travel had to do with visibility. But once I read about how comprehensive the shut-down was, it became clear that couldn’t be the issue. My girlfriend, an assiduous science blog reader, pointed me to Diandra Leslie-Pelecky’s explanation of the problem. She explains that it’s actually a multi-faceted issue, but the biggest problem is that the ash particles are small enough to get into the engines and then the heat melts them, causing them to stick on the turbine blades. And once the blade accumulates too much volcanic ash, the engine shuts down and your plane can’t fly anymore.
The last major Eyjafjallajökull eruption lasted for over a year so we may all be learning a lot about videoconferencing in the year future.