What happens when it all erupts again?

 As anyone who watches the news or has lived through a natural disaster knows, there is only so much that can be done to tame Mother Nature at her fiercest.

But when the ash cloud from Iceland's Eyjafjallajokull virtually closed down Europe's airspace for a week earlier this year, it was regulators who got the blame for being over-cautious and generally disfunctional in coordinating their response to the problem.

How much have we learned from that experience and what happens when  Eyjafjallajokull or one of her equally volatile neighbours decides to blow their top again? My colleague David Learmount spent last week at a conference on the effects on the volcano on aviation and came away with some slightly downbeat conclusions.

Our knowledge of the effects of volcanic ash remains an inexact science, he says in a Comment piece in this week's issue. Secondly, allowing airlines to take their own decisions whether to fly through low-level volcanic ash, based on available data, as they do with extreme weather, would require a massive mindset change among regulators from pure risk aversion to risk management. Not very likely.

See our 21 September issue for the full story and leader piece or read it here.