SYDNEY, Sept. 16 (Xinhua) – Researchers say smoke from Australia’s 2019 to 2020 bushfire season triggered a massive phytoplankton flower in the oceans between South America and New Zealand.
The study was published in the journal Nature on Wednesday, and lead researcher Peter Strutton from the University of Tasmania said they found links between phytoplankton flowering and the smoke triggered by forest fires.
In the summer that began in 2019, the Australian state of New South Wales experienced bushfires of unparalleled magnitude and intensity.
The fires burned through an estimated 5.3 million hectares or 6.7 percent of the state’s total land area and realized an estimated 715 million tonnes of carbon dioxide (CO2) in the atmosphere – more than Australia’s total annual emissions.
Using satellite images, the researchers observed that the smoke covers large distances through the Earth’s stratosphere before settling over the southern ocean thousands of kilometers off Australia’s east coast.
“The phytoplankton flowering in this region was unparalleled in the 22-year-old satellite record and lasted for about four months,” says Strutton.
The flowering was found to spread over an area of the sea larger than the entire Australian continent.
“What made it more extraordinary is that part of the season when the flowering occurred is usually the low point of the season on phytoplankton, but the smoke from the Australian forest fires completely reversed that,” said the researcher.
One of the seemingly positive consequences of rapid growth of the microscopic marine algae, phytoplankton, is its natural process of absorbing CO2.
Although it is estimated that the enormous levels of absorption were sufficient to compensate for the carbon dioxide emissions in the fires, Strutton warned that conclusions should not be hoped for in terms of the greater consequences of the phenomenon.
“We need a much more comprehensive representation of forest fires in climate models and targeted studies to understand their impact on marine ecosystems. Our ability to adapt to future climate change depends on it.”
Strutton said further research would be needed to determine whether the deposited CO2 is released back into the atmosphere or stored deep in the ocean after the event has passed.
The international expert Dr. Chris Mays from the Department of Paleobiology at the Swedish Museum of Natural History appreciated the importance of the substance and praised the importance of linking algal blooms to forest fires but warned of its impact on marine ecosystems.
“Explosive plankton flowers can be deadly to animals. A single flowering event can wipe out countless thousands of animals in a matter of days, leaving ‘dead zones’ in freshwater lakes and coastal areas,” he said.
He said that human activity makes such events more frequent and devastating.
“For these types of toxic soups, you need three main ingredients: high temperatures, high carbon dioxide and an influx of nutrients … People have provided two of these in abundance.”
Source: sn.dk