‘Mist was everywhere’: extreme weather driving North America’s pollen overload

Trees and grass are emitting more pollen than usual, scientists say - and it's likely to stay that way in the coming years

First, he had the symptoms. Then he saw the yellow fog. A thin layer of gold-coloured dust coated the patio furniture, the patio, his children's swing set - everything in the garden of Ubaka Ogbogu's home in the Canadian city of Edmonton.

The mist was everywhere. Even my kids - who are not typically observant about these things - remarked about this yellow everywhere," he said.