Researchers at the University of Colorado, Boulder, the U.S. National Oceanic, the Atmospheric Administration, and the U.S. National Center for Atmospheric Research have found that the massive wildfires from late 2019 to early 2020 in certain regions of Australia produced so much smoke, that it increased the temperature of the stratosphere in the area for about six months.

The gargantuan fires burned from approximately December of 2019 to January of 2020 and destroyed trees, brushes, and homes spreading around 14 million acres—killing 20 civilians. The researchers have found that black particulate matter in the smoke made its way into the stratosphere, leading to a slight temperature increase.

The stratosphere is about 10 to 50 kilometers from the surface of the Earth— it is also the part of the atmosphere that holds the ozone layer. Prior research has shown that in some instances, smoke can cool the atmosphere by blocking heat from the sun. In other cases, however, the opposite can occur. If smoke contains large amounts of particulate matter and it appears black, then it can absorb heat from sunlight and pass it to the air around it. To calculate how much heat was absorbed by the stratosphere, the researchers entered data from the fires into both the Community Aerosol and Radiation Model for Atmospheres and the Community Earth System Model.

Both data collectors were able to make predictions about how much heat was trapped by the particulate matter and the impact it would have on the temperature of the stratosphere in the region. They found that the stratosphere temperature increased from 1 to 2 degrees Celsius in the region and stayed that way for about six months. They also noted that the smoke particles temporarily increased the size of the ozone hole.