There is a “growing consensus” that climate change will impact the UK’s pollen season, the Met Office has warned, as it issues a “red warning” for hay fever sufferers.
The national forecaster has notified the public of “very high” pollen levels across much of England and in Wales this week, prompting warnings from campaigners of a “deadly” risk to people with severe asthma or chronic obstructive pulmonary disease (COPD).
According to the NHS, roughly one fifth of people in the UK experience hay fever at some point in their lives – and the health service revealed a surge in visits to its advice page this week, with one visit to the website every three seconds on Sunday.
There are several pollen seasons in the UK, with tree pollen occurring from March to mid-May, grass pollen from mid-May until July, and weed pollen through late June to September.
Research indicates that some pollen types are increasing in severity, with longer seasons which are starting earlier, with a study led by Dr Beverley Adams-Groom of the Met Office-backed pollen forecasting programme last year linking changes over the past quarter of a century to climate change.
Noting that incidences of respiratory allergies are at an all-time high, the study stated that most of the changes to pollen seasons it identified “were caused by climate drivers of increasing temperature and sunshine”.
“There’s a growing scientific consensus that climate change will impact the pollen season in the UK. It could result in longer pollen seasons,” a Met Office spokesperson told The Guardian this week.
“We are seeing lots of high count days because the weather is very suitable for pollen emission from grasses,” said Dr Adams-Groom told the paper.
“The problem for hay fever sufferers is not so much the size of the pollen count, since any amount over 50 pollen grains per cubic metre of air is problematic for the majority, it is more the perpetual onslaught of high days, due to the almost continuous good weather in many regions since the season began in late May/early June.”
However, Dr Adams-Groom said that the grasses will become exhausted more quickly if the hot weather continues into next week, giving some respite to hay fever sufferers, adding: “Already, I am seeing some evidence that this is happening, with grasses going over very quickly.”
Among the key findings of the 2022 study was the fact that oak and grass pollen seasons are starting earlier, while the birch season is getting more severe.
The research also highlighted how increasingly atypical weather caused by climate change has coincided with increasingly erratic pollen seasons, with a trend towards lower wind levels reducing dispersal of grass pollen grains in the summer.
“Climate change is impacting on seasons,” Dr Adams-Groom previously said of the study. “It’s difficult to predict the long-term future as there are many factors at play. What we do know is that there are going to be more extreme weather events – that’s documented, and that can impact on the seasons.”
High pollen levels can be very dangerous for those with conditions such as asthma, bringing on serious symptoms like wheezing and breathlessness,” Emma Rubach of the charity Asthma + Lung warned this week.
“They can prompt asthma attacks which can be terrifying, leaving them fighting to breathe,” Ms Rubach told the MailOnline. “This can be deadly and around four people already die in the UK each day from an asthma attack.”
