UK to deploy volcanic ash detector network around the country

A network of ash detectors will be installed across the United Kingdom to help prevent volcanic ash cloud shutting down European airspace, costing billions of pounds to airlines and inconveniencing passengers.
"We've got three bands of ash - low, medium and high, which is defined by the amount of ash in the air - that defines where airlines can fly," said Jonathan Nicholson of the Civil Aviation Authority.
Working out whether an ash cloud is low, medium or high is where the new government-funded network comes in, the BBC reported.
The network will be made up of 10 instruments called Light Detection and Ranging Systems, or Lidar.

The equipment uses lasers to work out how dense a layer of ash cloud is and that data can be used to work out if that cloud is safe to fly through.
Aviation Minister Robert Goodwill said: "This new equipment will allow the UK's Met Office to track ash clouds more easily and predict how they might spread more accurately.

"That could play a big part in minimising disruption to flights during any future incident."
The ground-based network will be used in conjunction with the world's only plane specifically kitted out to detect volcanic ash particles.
An ash cloud from Icelandic volcano Eyjafjallajokull led to many airlines cancelling thousands of flights across Europe for six days in April 2010. The cost of closing the airspace cost airlines more than 1 billion pounds.

The Met Office Civil Contingency Aircraft (MOCCA) has its own Lidar and that data will be added to that collected from the ground network to help formulate the ash cloud forecasts.
"The Lidar has a laser that reflects off clouds and goes into a telescope, within the instrument, which detects the reflected laser light," Met Office scientist Joss Kent said.
"If particles in the cloud are volcanic ash they will reflect in a different direction compared to other particles due to its shape - and the Lidar can measure that change in direction.
"If a cloud's not too thick the laser is powerful enough to fire all the way through that layer and we can see out the other side, which is useful for us as we know it will be safe the other side to fly."

Kent added that the data is transmitted in real time from the aircraft to Exeter, where it is examined to determine how to adapt the forecasts.
The added of advantage of the MOCCA being used with the new network is that the aircraft will be able to get more targeted measurements of ash in areas that the ground-based network cannot see.
The active volcanoes of Iceland will continue to present a risk to air travel in future, but the combination of improved detection, better forecast capability and more flexible safety regulations will minimise disruption next time around.