Absence of aircraft a clear risk to our skin
UV readings ‘off the scale’ as mercury rises, and blue skies are untainted by the contrails of airliners
THE lack of planes in the sky could contribute to the UK reaching its highest levels of UV radiation today, on the hottest day of the year so far.
Levels of UV rays, which can cause sunburn and raise the risk of skin cancer, are expected to reach as high as nine in Devon and Cornwall, a level more common in the Mediterranean.
“That’s about as high as it gets really in the UK,” said Alex Burkill, a meteorologist. The Met Office raised the heathealth alert level to three yesterday and warned people to take care in the sun as temperatures reached 33C (91.4F).
The main factor in high UV levels was a hole in the ozone layer that opened earlier this year, said Michaela Hegglin, a professor in atmospheric chemistry at the University of Reading.
The other key factor was the time of year, so close to the solstice, which meant the sun was at its most powerful, combined with high pressure limiting cloud cover and water vapour in the atmosphere. “We’ve got peak sun strength, clear skies and plenty of sunshine – it’s the perfect ingredients for high UV,” Mr Burkill said.
Another contributor was most likely the absence of plane contrails, which would normally create clouds that reflect UV rays away from the Earth, Prof Hegglin said. Flights are still at a fraction of pre-pandemic levels.
Keith Shine, Regius Professor of Meteorology and Climate Science at Reading University, who is overseeing research into the impact of the drop in flight volume during the pandemic, said the lack of contrails was certainly a factor in UV levels “in areas like the UK with a high volume of air traffic”. But Prof Hegglin said the positive impact of lower levels of air pollution and greenhouse gas emissions vastly outweighed the negative impact of UV levels, particularly in Britain, where they were already relatively low.
She said people may need to take more precautions to protect themselves against the harmful effects of UV rays as we moved toward adopting cleaner transport systems. She added:
“UV levels this high are rare in the UK, so people with light skin should be very careful to avoid getting burnt. While UV is important for getting Vitamin D, and keeps us healthy, too much of it can cause skin cancer or cataracts.”
People were warned yesterday to take extra precautions in the hot weather, particularly as they may face a longer time outdoors because of queues caused by the social distancing measures.
London Fire Brigade warned of the increased risk of wildfires, and cautioned against holding barbecues on dry grass or discarding cigarette butts and matches.
Jo Churchill, the health minister, advised people to stay safe after the Met Office said that older people, very young children and those with underlying health conditions were particularly vulnerable.
“Apply sunscreen regularly, stay hydrated and protect your head from the sun,” she said.
But the Government was accused yesterday of waiting too long to raise the alarm over high temperatures.
Amber level three, which yesterday was put in place for the West and East Midlands, puts healthcare services on alert to prepare for threats to high-risk groups.
Bob Ward, the policy director at the London School of Economics’s Grantham Institute, said the alert “may have come too late” for the most vulnerable, including Covid-19 patients.
An official review of the Government’s heatwave warning system conducted last year by the London School of Hygiene and Tropical Medicine found up to 90 per cent of heat-related deaths occurred before the official alert thresholds were reached. He warned that climate change was increasing the frequency and intensity of hot weather.