A fresh example of global climate interconnectedness has emerged in the effects of Australia’s catastrophic wildfires of 2019-20 playing out across the world.
The study was published on May 10 by Science Advances, a peer-reviewed multidisciplinary open-access scientific journal. It said the Australian wildfires contributed to a rare three-year La Niña from late 2019 through 2022 as the smoke it emitted shifted the cloud and rain belts.
“Many people quickly forgot about the Australian fires, especially as the covid pandemic exploded, but the earth system has a long memory, and the impacts of the fires lingered for years,” said atmospheric scientist John Fasullo, the lead author of the study.
The research was funded by the US National Science Foundation, NASA, and the US department of energy.
Widely regarded as one of the worst in history, the Australian wildfires of 2019-20 blackened more than 60,000 square miles of land, killing dozens of people and an estimated one billion animals. Their massive spread followed a period of extreme drought and record-breaking temperatures in the region.
The Science Advances study found that the blaze set off a three-year La Nina, a phenomenon triggered by the cooling of the earth’s surface caused by an exceptional amount of smoke in the atmosphere.
This episode of La Nina left many parts of the world under extreme conditions, fatal for human life. These conditions include one of the most severe droughts in Africa, that threatened millions of people with starvation. The drought left food prices skyrocketing. The Atlantic Ocean region, meanwhile, experienced some of the worst tropical storms in 2020.
Scarily, this was just the beginning, the study says. Its authors warn that the fires and La Niña “may become more prevalent under climate change as wildfires are projected to intensify and become more frequent.”