DUBLIN — Iceland's clouds of volcanic ash are menacing European air traffic again, but transport chiefs insist they are learning from last month's crisis and won't let the hard-to-measure emissions ground their continent again.
Rising volcanic activity spurred aviation authorities in Ireland, northwest Scotland and the Faeroe Islands to shut down services Tuesday after a two-week hiatus. Their airports reopened several hours later, once the densest ash clouds had passed over their airports and back over the Atlantic.
But soon a new wave of engine-damaging ash was approaching British airspace, forcing Britain's Civil Aviation Authority to announce that airports in Scotland and Northern Ireland had to cancel all services indefinitely, beginning at 6 a.m. today.
The British authority said its forecasters had determined that ash in United Kingdom airspace "has increased in density." It said the prevailing winds would probably continue to push the threat southward, "potentially affecting airports in the northwest of England and North Wales tomorrow" — but missing the key European air hubs in London.
Earlier, travelers and transport chiefs alike said Europe was learning to pinpoint the true nature of the threat versus last month's better-safe-than-sorry shutdown of air services for nearly a week in several countries. Airline and airport authorities branded that response overkill; it grounded 100,000 flights and 10 million passengers and cost the industry billions of dollars.
European Transport Commissioner Siim Kallas emphasized that, had last month's sweeping safeguards been imposed Tuesday, "a very large part" of Europe would have lost its air links again — and for days, not hours.