Billions of animals were killed in Australia's Black Summer fires. Major cities were smothered, glaciers turned distant brown, and fatal health emergencies occurred.
Researchers have traced the cause of the biggest warming in three decades and messed with the ozone hole.
Combining satellite data with surface-based observations of aerosol behavior in computer models allowed Lilly DamanyPearce and colleagues to detect the smoke as it floated high into our planet's atmosphere.
The fires consumed over 5.8 million hectares of life and formed their own weather systems that lasted for days at a time.
The smoke was pumped into high altitudes by the systems and the Sun's rays heating the dark particles and causing them to rise further.
On December 31st, the first vortex reached an altitude of 16 kilometers. Up to 35 km into the sky was detected from 12 January 2020 and it lingered for up to two months.
The team writes in their paper that the aerosols were detected in the upper atmosphere by NASA instruments and surface-based lidars from the southern tip of South America.
There was a sudden global mean temperature spike of 0.7 C.
The researchers' climate modeling showed that the temperatures could not be explained by the injected smoke particles.
DamanyPearce and team note that this was the largest temperature spike since the eruption of Pinatubo volcano.
While the planet's surface cooled by about half a degree Celsius due to diffuse clouds of particles blocking sunlight, the absorption of infra-red radiation by particles in the stratosphere caused that layer of the atmosphere to warm.
Recent studies show that particulates from wildfires can deplete the ozone layer, and that aerosols from volcanic eruptions can do the same.
Ozone molecule are used in chemical reactions on the surface of smoke particles The researchers mapped the ozone distribution in the southern hemisphere in 2020 and found more evidence of the ozone being damaged by smoke.
The smoke particles increased the duration of the ozone hole and disrupted the polar vortex, which usually breaks down at the end of spring.
In their paper, DamanyPearce and colleagues explain how ozone depletes to increase the strength of the polar vortex.
The ozone hole that was observed in 2020 was caused by this.
We know why the ozone hole reached a record level in 2020. The new research shows how smoke-caused changes in the atmosphere impact the temperature. The spring of 2020 in the southern hemisphere was cool.
More of the problematic smoke particles floated over the ocean and fell into the sea, spurring plankton into a feeding frenzy and creating a suffocating bloom of these microorganisms larger than the smoke's continent of origin.
It's more concerning than ever to see how large, varied and far-reaching the effects can be on the environment.
The research was published in a peer-reviewed journal.
All Rights Reserved © 2024
