The old computational forecasting wizards at the Met Office are behind the decision of closing so much of Europe’s airspace.
Of course they are.
(yes, it’s “well-proven” models, no direct measurement, the works!)
From the Herald Sun:
German airlines Lufthansa and Air Berlin said the decision to close much of Europe’s airspace was not based on proper testing. They said that their aircraft showed no signs of damage after flying without passengers.
“The decision to close the airspace was made exclusively as a result of data from a computer simulation at the Volcanic Ash Advisory Centre in London,” Air Berlin chief executive Joachim Hunold said.
The “Volcanic Ash Advisory Centre in London”? Here it is, at the Met Office:
When a volcano in its area of responsibility erupts, the London Volcanic Ash Advisory Centre (VAAC), based at the Met Office, runs the NAME atmospheric dispersion model. This, and similar models, are well proven and we can use them to predict the spread of pollutants following a chemical or nuclear leak or even the spread of airborne diseases. In this case we use the dispersion model to forecast the spread of volcanic ash plumes.
The London VAAC forecaster provides the location, start time, release height and the top and bottom of the plume (if known) and the model is run. It takes about 15 minutes to complete.
Output from this model is in a map-based graphical format, and can detail expected ash concentrations over a large region. The forecaster uses this detail to prepare the volcanic ash advisory message with the expected positions of the ash plume for up to 24 hours ahead.
The Advisory message is then used by aviation authorities to decide whether airspace needs to be closed to prevent aircraft encountering volcanic ash.
Note how the Met Office washes its hands from any decision, and yet in all those years with NAME, it has apparently decided not to complement the model results with in-situ measurements. A “revolutionary” idea brought forward at present by Lufthansa itself…
“Not one single weather balloon has been sent up to measure how much volcanic ash is in the air.” Lufthansa spokesman Klaus Walter added. “The flight ban, made on the basis just of computer calculations, is resulting in billion-high losses for the economy […] In future we demand that reliable measurements are presented before a flying ban is imposed.”