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How do we measure pollen?

Hay fever
How do we measure pollen?

tree pollen

Every summer, one topic that is never far from any conversation is that of pollen and hay fever. But ever wonder how a pollen forecast is made?

Fear not, there is no need to head outside and begin counting each minuscule speck of pollen as it wafts through the air. Instead, a tool called a ‘rotorod’ is used.

This device is designed to measure pollen and fungus spores in the air. Essentially, coated clear rods are placed in a field, encased within a small structure to protect it from weather, and checked every day to see how much pollen is stuck to it.

From this number we can determine the units of pollen per cubic metre of air and from there, place a pollen level in that area to inform hay fever sufferers of the day’s hazards.

Because of the method used, it is not possible to be 100% accurate for pollen levels in every region, but we can uncover a trend for your area.

With recent heatwaves, you may find that your hay fever is a little less severe. While warm, breezy days result in more pollen, temperatures over 28°C can actually reduce the amount and long periods of heat can halt the release of pollen altogether.

Pollen seasons changing with climateread more

If you are heading out to make the most of the sunshine, be sure to check the pollen count in the Weather & Radar app.

Ryan Hathaway
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