The Eyjafjallajökull ash cloud of 2010 exposed serious weaknesses in the ability of governments across Europe to prepare for an aviation crisis and implement effective responses.
One year on considerable efforts have been made to improve scientific understanding, reform the risk management approach and improve coordination at the European level. A major scenario exercise in April this year even took Grimsvötn - the volcano now erupting - as its case study. Successful management of this eruption would have five characteristics:
European countries take a consistent approach
In 2010, European countries made different decisions, based on the same scientific advice, leading to widespread confusion. This is the first test of a new set of guidelines which allows planes to fly in low and medium concentrations of ash, and puts much of the risk assessment decision-making in the hands of the airlines. Ultimately, the responsibility for aviation safety remains with individual countries. Yet a single Europe-wide system for submitting the safety assessments is not yet in place, and Eurocontrol has confirmed that some European states are not yet ready to implement the new approach - especially those who did not take part in the recent scenario exercise.
Decision-making is decisive and transparent at European level
Last time round, European-level organisations took a back seat for nearly a week. A clear structure of decision making across key bodies must emerge if public confidence in decision making is to be maintained - including Eurocontrol, the European Aviation Safety Agency and the European Commission. Coordination will be undertaken through the European Aviation Crisis Coordination Cell (EACCC), an emergency mechanism that has been activated for the first time since Eyjafjallajökull. Transparency at European level is another key test. The detailed remit and composition of the EACCC - including the level of industry participation - remains cloudy.
The aviation industry supports the best available scientific information
The accuracy of Met Office ash maps was a major point of contention between airlines and engine manufacturers on the one hand, and aviation safety regulators on the other. A new ash measuring station in Iceland (still undergoing calibration) and refinements to the modelling has reduced uncertainty, but this can never be an exact science. Tension should have been reduced by the shift of responsibility towards airlines.
Governments provide clear information to the public
Scientific and technology uncertainty is notoriously difficult to communicate, especially when it comes to articulating risks and probability. Yet this is crucial to maintain public confidence in evidence-based decision making. During the last crisis, there was scant public defence of the precautionary principles or safety.
Governments also failed to establish a clear public understanding of passengers' rights when flights are delayed. Instead the media discourse was dominated by airlines duelling through the airwaves to step up pressure to remove the flight ban. Already, it is clear that stakeholders have chosen very different media strategies to last time - notably Eurocontrol which has been lauded online for its activity on social media.
The knock-on consequences of the disruption are managed effectively
A prolonged disruption to aviation would have widespread economic and social impacts. How to manage these impacts has received much less attention over the last twelve months than the issue of when to fly in ash. If Grimsvötn erupts for longer than currently anticipated, similar challenges for cross-border transport management will emerge, followed by questions about appropriate state support for struggling businesses.