Significant enhancements of nitrogen oxides, black carbon, and ozone in the North Atlantic lower free troposphere resulting from North American boreal wildfires

Emissions from these wildfires frequently impacted the PICO-NARE station, a mountaintop site situated 6-15 days downwind from the fires in the Azores Islands. To assess the impacts of the boreal wildfire emissions on the levels of aerosol black carbon (BC), nitrogen oxides and O₃ downwind from North America, we analyzed measurements of CO, BC, total reactive nitrogen oxides (NOy), NOx (NO + NO₂) and O₃