The UK and Ireland are facing new disruption due to the return of Icelandic volcanic ash.
No-fly zones have been imposed over northern England and flights in and out of Belfast and other parts of Northern Ireland were stopped.
The potentially dangerous ash is again heading south-east from Iceland.
Expert David Rothery said: “The ash cloud is becoming a problem again because the activity at the volcano has intensified. It’s not as intense as it was when the problem began a month ago.
“But certainly throughout today grey ash has been injected high up into the sky to several kilometres, maybe about 20,000 feet (6,000 metres) and that’s been caught by the high altitude winds and it’s been blown towards Scotland,” he said.
While no-fly zones have been imposed over northern Ireland, airports in London are so far not affected.
Ash cloud affects England and N.Ireland