Smoke from the Black Summer wildfires in Australia impacted the climate and high altitude winds of the southern hemisphere for more than a year and a half

TROPOS analysis: Wildfire smoke becomes increasingly important for climate models due to climate change

The 2019/20 wildfires in Australia transported more smoke into the atmosphere than observed ever before anywhere in the world. In the so-called Black Summer, three times as many particles reached high air layers as in the previous record wildfires in Canada during summer 2017. Two analyses led by the Leibniz Institute for Tropospheric Research (TROPOS) now reveal the climate impact of these huge fires: Smoke particles with a total mass of around one million tonnes spread across the southern hemisphere and affected the climate for about one and a half years by warming the upper atmosphere and cooling the lower atmosphere close to Earth’s surface. From the subtropics to Antarctica, sunlight was dimmed even more than during the eruption of the volcano Pinatubo in 1991. The smoke probably also contributed to the record ozone hole over Antarctica in 2020, forming a vortex of 1000 kilometres in diameter that passed over the southern hemisphere for several weeks, which is considered the first evidence that smoke from wildfires can also alter high-altitude winds in the stratosphere. Since such extreme fires are expected to become more frequent due to climate change, it is very important to consider the smoke and its effects on the Earth’s energy balance in climate scenarios, the researchers write in the journal Atmospheric Chemistry and Physics (ACP).