Smoke from Canadian wildfires has been detected thousands of kilometres away in Norway this week, the Scandinavian country's Climate and Environmental Research Institute NILU said on Friday.
"Very weak" concentrations of smoke particles have been detected since Monday, in particular at the Birkenes observatory in southern Norway, researcher Nikolaos Evangeliou told AFP.
Measurements have varied depending on the fires' intensity, wind direction and precipitation.
"We don't see serious peaks or large increases... so we don't see any environmental issue (in Norway) nor serious health hazards either," he added.
Larger and more powerful wildfires than ever have scorched some 3.8 million hectares of Canadian forests and displaced tens of thousands of residents in recent weeks.
The scale is unprecedented, with some 2,300 fires registered so far this year.
Southern Norway, like much of northern Europe, has also experienced an unusually dry spring and early summer so far.
In southern Norway, no rain has fallen for 16 days and none is forecast for the coming days.
A three-week ban on fires in open spaces was introduced on Thursday.