Smoke from wildfires in Southern Europe has brought hazy conditions to the UK, disrupting the current heatwave, forecasters have said.
The UK experienced the fourth heatwave of the summer this week, with some areas seeing the mercury climb above 33C in the hottest places.
However, the Met Office said “smoke from wildfires in Spain and Portugal, plus Saharan dust, has drifted over the UK”.
This means the UK should expect “enhanced sunsets and sunrises in the coming days – deeper reds and oranges thanks to light scattering,” the forecaster added.
Scientists say the phenomenon is linked to two processes known as Rayleigh scattering and Mie scattering.
Rayleigh scattering, caused by tiny air molecules, normally makes the sky appear blue by scattering shorter wavelengths of light, such as violet and blue, according to the Royal Meteorological Society.
But larger particles released by wildfires, such as soot and ash, trigger Mie scattering, which scatters all wavelengths more evenly and allows longer red and orange wavelengths to dominate.
Met Office meteorologist Greg Dewhurst told Sky News the haze “will hang around for the next few days”.
The Met Office’s forecast for Sunday says low clouds retreating towards the North Sea means there will be “plenty of sunshine for most”. There will be strong winds in the South West of England, and it will remain warm along the eastern coast.
Spain battled 14 major fires driven by high winds and aggravated by heat on Friday as authorities warned of “unfavourable conditions” to tackle flames that have already killed seven people and burned an area the size of London.
Firefighters have been battling to put out blazes across southern Europe in one of the worst summers for wildfires in 20 years.
An early two-week heatwave and southerly winds were worsening the situation in Spain, Virginia Barcones, director general of emergency services, said.
Wildfires have burned more than 157,000 hectares in Spain so far this year, almost double the annual average, according to the European Union’s Forest Fire Information Service.
In neighbouring Portugal, meanwhile, thousands of firefighters were battling five large blazes in central and northern parts of the country, with one fire in Trancoso, some 350 km northeast of Lisbon, now raging for six days.
Europe has been warming twice as fast as the global average since the 1980s, according to the EU’s Copernicus Climate Change Service.
The EU monitoring agency says that 2024 was the hottest year on record both globally and in Europe, which experienced its second-highest number of ‘heat stress’ days.
