July 30, 2014
I once heard an American comedian who had moved to London quip that he had been in England for two summers. “So I’ve lived here about ten years now,” was the punch line to that particular comedy gem.
Suffice to say his name eludes me and I’ve never had the urge to look him up and see his show again.
But I suppose I would reluctantly have to admit a grain of truth can be harvested from his thoughts –England doesn’t do summers often, but when she does, she does them in style.
And this year, touch wood, seems to be turning into one of those. Despite an unpromising start the heat recently has been fantastic, the skies have been clear and all has been well with the world. That is unless you’re a hay fever sufferer.
With the hot weather comes high pollen counts and if you live in the countryside, with harvest just getting underway, that is set to get worse. Best stock up on antihistamines if you’re one of the many thousands of people affected.
Nowadays of course the pollen count is routinely reported on the weather, so we know when to break out the tablets and when to leave them at home. But have you ever wondered how it is actually calculated, how scientists know how many of the microscopic misery causers and actually floating about?
Pollen levels are actually measured in what is called a Burkhard volumetric spore trap, which is a garden chair-sized contraption that is placed about two storeys above ground level.
Inside the trap is a rotating drum with a wax-coated sticky tape. An aperture on the trap sucks in air at a regulated speed, depositing anything in the air onto the drum.
They are placed at various locations around the UK and the contents are analysed every day at 9am to produce pollen forecasts for the ensuing 24 hours.
This information is then sent to the Met Office to be incorporated into the weather forecasts.
Pollen is measured in grains per cubic metre and anything in excess of 150 grains per cubic metre is considered high.
So far this summer the highest pollen count has been recorded at York University, which was a sneeze-inspiring, eye-watching, nose-running 801 grains per cubic metre.
To find out more about the pollen count visit www.metoffice.gov.uk