Bright sunshine in recent weeks heralds the arrival of spring in Germany, and any minute now it will bear fruit: with watery eyes, sneezing and red noses stuffed with pollen.
Starting this Monday in the southwestern city of Freiburg, though, allergy sufferers are going to get a much clearer picture of the exact causes of their sneezy misery. The German Weather Service (DWD) is rolling out the first two of its planned 15 new high-tech pollen stations.
The advanced measuring instruments contained in 1.8-meter-tall boxes rely on real-time microscope scans of gel traps to identify the tiny grains of ambient pollen in the air.
Weather stations around the country already collect data on pollen clouds for media outlets and research centers, of course, but the new stations are automated, faster and supply a much greater level of real-time detail. This can be crucially important for the discerning allergy sufferer who might be impervious to the oncoming clouds of ribwort in the air, but susceptible to vicious ragweed.
Developed by a team of researchers at the Fraunhofer institutes for Applied Information Technology and Toxicology and Experimental Medicine along with the Hessian optics company Helmut Hund, the stations work by focusing a conventional optical microscope inside the box onto a sheet of glass covered with a gel.
The equipment has an air intake which filters out dust and impurities; the remaining pollen settles onto the gel plate. That's where the innovation begins, says Fraunhofer researcher Thomas Berlage. The automated microscope then begins taking pictures of the grains. Normally these images would show the pollen as two-dimensional circles, nothing more. But the station microscope's been programmed to re-focus itself and take up to 70 different takes on the same item – slices which provide three-dimensional information by layering the images.
In this way, it works kind of like the CAT scans we're familiar with from hospitals, Berlage says, only slightly different.
“The grains are mostly transparent, as is the gel in which they are embedded. The information about the kind of pollen is in the shape and structure of the surface,” he says. “As the interior is mostly without information, we invented a mechanism that basically flattens the top 3D surface of the grain into a 2D disc.”
This image is then fed into a classification system based on mathematical descriptors that matches the pollen image to a database.
The new system should be able to deliver updated results every two hours, and this data will be fed to the weather service over a net connection. Uwe Kaminski at the German Weather Service says 15 of these sensor stations are on order to be placed at weather research facilities across Germany, from Freiburg to Friesland over the next two years. They'll be set up at the same locations as existing facilities; for example the Freiburg station will be plugged into the system at the DWD operations centre.
The new equipment is going online just in time too – Germany is ripe for a heavy pollen season, since the long winter means that many plants will be starting their reproductive efforts at the same time. You'll still have to remember your hankie, but at least you're going to know why your eyes are watering and your nose is stuffy.
Pollen experts will have a much better idea how bad it will be by the time the vast clouds of poplar flax start settling onto city parks across the country in a couple weeks.
But that poplar “cotton” is not the cause of your allergies – it's made from large particles and frequently gets a bum rap for coming out the same time as the tiny grass seeds which are really the ones making you sneeze.