How long do we have to wait before economics get the better of health and safety concerns, and more importantly who is doing the science?
I have no idea if it is being done, but after six days of the no fly zone I hope that someone, of preferably a number of different someones are flying balloons, propellor planes, drones and anything else through the Eyjafjallajokull ash cloud and sampling its density, size distribution and composition before using this data to simulate the effect on jet engines.
This may not be the last time we face a problem like this, so we really should be figuring out what steps need to be taken, something that London Mayor Boris Johnson is also concerned about. As a frequent flier rather than a pilot, I am aware that there are procedures to cope with a wide variety of incidents, from technical failures to foul weather, so we should be looking at adding one more to the list.
Is anybody doing anything? If we could collect micrometeorites by attaching double sided tape to 747s twenty years ago, sampling an ash cloud should be relatively simple.
Eyjafjallajokull Ash Particle Size Distribution
An interesting piece of work from Þröstur Þorsteinsson at the Nordic Volcanological centre looks at the particle size distribution from the Eyjafjallajokull eruption.
Thorvaldur Thordarson quoted in The Economist explains
Ash particles are normally in the 50-100 micron (0.05 to 0.1 millimetre) range. But at a site 50km east of the eruption, 24% of the ash falling to the ground was in the form of particles 10 microns or less in size. Studies of ash captured from the air show that for every one of the largest particles (about 300 microns) there are a million or more in the 2 micron range. So though the total volume of the eruption, put at about 0.14 cubic kilometres, is low, the amount of ash capable of travelling long distances is high.
While the measuring instruments only seem to go down to 2 microns or so, given the distribution profile it is a fair bet that Eyjafjallajokull is producing large amounts of nanoparticles. It would be good to see some more distribution data, perhaps using this type of instrument?
The ash cloud heads south east....
While the eruption of Eyjafjallajokull in Iceland is bad news for some people, it is actually quite interesting from an emerging technologies point of view, and bordering on fascinating if, like me, you somehow managed to shoehorn a big chunk of geology and geomorphology into you education (It’s a frightening thought, but I could have ended up as a geographer!) as well as spending time working at the European Space Agency.
One of the more frequently proposed geoengineering solutions to climate change is to eject large amounts of aerosols into the upper atmosphere which then cut down the amount of solar radiation reaching the earth. The eruption of Mount Pinatubo and the twenty million tons of sulphur dioxide it blasted into the stratosphere was thought to have caused a global cooling of half a degree centigrade, more than offsetting human induced climate change.
One of the key arguments against geoengineering is that we don’t know what the effects would be – and it is also a good idea to know how much the earth is warming by and what is causing it before you start to try to reverse it – but in this case we are learning fast, and collecting huge amounts of data from dozens of earth observation satellites, many of which were launched in response to concerns about climate change and designed specifically to measure it. So this particular eruption may be the one which helps us make that (hopefully) rational and evidence backed decision to use geoengineering should if ever become necessary.
While Eyjafjallajokull is estimated to be spewing ten thousand times less sulphur dioxide into the atmosphere than Pinatubo, the highly sophisticated earth observation satellites launched since Pinatubo’s 1991 eruption means that we are far better placed to study the effects of the eruption, both on the planet as a whole, and as a result of the particular composition of material ejected.
Ash sweeps across Europe, as seen from Envisat
This animation from the European Space Agency shows both the spread of the cloud, and its concentrations of sulphur dioxide, and ESA already has a project named Globvolcano which will “define, implement and validate information services to support volcanological observatories in their daily work by integration of Earth Observation data, with emphasis on observation and early warning.”
The other interesting bit of science we can do this week is investigate the effect of aircraft vapour trails. The water vapour emitted by jet engines has a similar effect to high altitude cud, reducing the amount if radiation reaching the earth during the day and acting as an insulating layer during the night. Work carried outwhen all aircraft were grounded in the US after the September 11th attacks concluded that “Sept. 11-14, 2001, had the biggest diurnal temperature range of any three-day period in the past 30 years.” As with all science, taking a single data point doesn’t prove anything, so having another crack at it might help us understand the effect of aircraft on the climate.
All in all, it’s pretty exciting stuff, and armed with half a dozen earth observation satellites like Envisat bristling with spectrometers there is the opportunity to do some great science.
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