Tens of thousands of air travelers around the world are stuck today, as a mammoth cloud of ash from an Icelandic volcano has shut down all air traffic over Britain, Ireland and the Nordic countries.

“At the present time it is impossible to say when we will resume flying,” said a spokesman for Copenhagen’s airport in Denmark.

The U.K’s air traffic service has banned all non-emergency flights until at least 7 a.m. Friday. The airport with the most affected travelers is London’s Heathrow International, with over 1200 flights and 180,000 travelers moving through its gates each day.

Additionally, many European airports are experiencing shutdowns and flight cancellations. U.S. airlines, which often need to travel through the currently closed air space en route to destinations in Europe, are working to re-route the flights that haven’t been canceled.

In addition to causing visibility problems, volcanic ash can wreak havoc with a jet’s systems, clogging up engines, blocking sensors and more.

“When there is lava erupting close to very cold water, the lava chills quickly and turns essentially into small glass particles that get carried into the eruption plume,” said Colin Macpherson, a geologist with the University of Durham. “The risk to flights depends on a combination of factors — namely whether the volcano keeps behaving the way it has and the weather patterns.”

Volcanic Ash Cloud Halts Flights Across Europe[FoxNews]

Thanks to Justin for the tip!

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