GENEVA — Airlines canceled hundreds of flights across Europe and added hours to trans-Atlantic journeys Sunday as planes were diverted around a large plume of ash spewed by an Icelandic volcano and stretching from Greenland to Portugal.
So far, the weekend cancellations have been a fraction of the flights nixed two weeks ago when jittery European air traffic authorities closed down much of the continent's airspace for fear the volcano's abrasive ash could harm jet engines. But the possibility loomed of continuing eruption and rising costs to airlines from ongoing disruption.
The bulk of the cloud, measuring 2,100 miles long and 1,400 miles wide, stretched over the North Atlantic, according to the Irish Aviation Authority. It ordered Ireland's five westernmost airports to close Sunday afternoon but allowed the country's three biggest airports in Dublin, Shannon and Cork to stay open.
Airlines diverted their trans-Atlantic traffic north and south of the cloud, causing congestion as planes tried to squeeze through remaining routes. Some connections were canceled entirely because of an offshoot of the main cloud that was snaking its way from Portugal through Spain, southern France and northern Italy, then up to Germany, the Czech Republic and Austria.
Eurocontrol, the Brussels-based agency that coordinates air traffic control centers throughout the continent, warned airlines to plan on taking on more fuel for the longer flight around the North Atlantic no-fly zone.
It said there would be about 24,500 flights within the European area Sunday, about 500 below average for this time of year. It said the ash cloud hovering over the continent was expected to dissipate.
Daniel Gerstgrasser, a meteorologist with Switzerland's national weather agency, said that rain would help wash out the cloud by this morning and that no further ash drifts were expected to reach the continent in the coming 24 hours.