Volcanic Ash in the European Airspace

Airports in Europe and Asia are restoring flights after six days of restrictions due to a volcanic eruption under Iceland's Eyjafjallajokull glacier, which has caused a plume of volcanic ash to spread over Europe's airspace. The volcanic ash has led to the cancellation of over 100,000 flights, and it could take some time for air traffic to return to normal, according to this article in the New York Times.

This page from the U.S. National Oceanic and Atmospheric Administration (NOAA) explains that volcanic ash is often in the air. A worldwide network of Volcanic Ash Advisory Centers (VAACs) monitor the atmospheric impact, issuing advisories when necessary. NOAA operates two of these VAACs, while the London VAAC monitors volcanic ash over the UK, Iceland, and parts of the North Atlantic Ocean. The London VAAC provides some informative pages about its forecasting methods, detection tools, and observations:

• Observations of volcanic dust over Great Britain (April 20, 2010)
• Volcanic ash forecasting
  
• Volcanic ash detection tool

To find other governmental resources about the atmosphere, see our guide to Climate and Weather.