The scorching destruction of Australia’s black summer fires between 2019 and 2020 has provided a disastrous look at the spread of fire in our hottest and drier world, and the impact of unprecedented hell is still being measured.
Just a few weeks ago, scientists noticed that the amount of smoke thrown from the flames into the atmosphere rivaled that of a large volcanic eruption. Now, researchers say the huge cloud of smoke was so huge that it measured the stratosphere measurably for months.
In a new study led by the first author and modeler of climate Pengfei Yu at China Jinan University, scientists simulated the appearance and evolution of the feather, showing that the worst documented fires in Australian history have left a lasting impact on the region’s sky. .
“Extreme fires can inject smoke into the upper troposphere and even into the stratosphere under favorable weather conditions,” the researchers write in their paper. “The higher the smoke injected, the longer it will last and the more widespread it will be.”
In the case of the black summer fires, the flames sent nearly a trillion grams (about 0.9 teragrams) of smoke particles into the stratosphere, which the researchers explain is the largest amount ever documented in the satellite era.
This mass of smoke was composed of different types of smoke particles, including both organic carbon (OC, which includes brown carbon, aka BrC), and black carbon (BC).
Each of them has different effects of capturing heat in the atmosphere, BC being the most captivating heat, due to the way it heats the surrounding air after sun absorption.
According to the researchers’ calculations, the black summer feathers were composed of about 2.5% carbon black, which contributed to providing a warming effect in the stratosphere, which lasted the rest of the year.
“The simulations suggest that the smoke remained in the stratosphere for the whole of 2020 and that it warmed the stratosphere measurably by about 1-2 K [Kelvin, equivalent here to 1-2 degrees Celsius] more than six months, “explains the team.
“Our study shows that record smoke can cause persistent impacts on stratospheric dynamics and chemistry.”
In addition to warming the stratosphere, the researchers say the record smoke event also had a diminishing effect on the ozone level in the stratosphere, destroying ozone molecules in the upper-middle latitudes of the southern hemisphere and probably making the ozone hole. temporarily larger.
While researchers acknowledge that observations of aerosols that produce stratospheric warming have been made before, it is the first time scientists have measured the phenomenon to such an extent, given the record production of black summer fires.
The findings are reported in Geophysical research letters.