The massive drop in atmospheric ozone levels around the tropics around 60 to 100,000 years ago is finally explained. An international research team found new shocking details, unveiling the culprit.
As per the team’s discovery, the major ozone loss was triggered by the eruption of the supervolcano Toba (present-day Indonesia), contributing to a bottleneck in the human population at that time. So how the team succeeded in getting enough proof?
Here is what you need to know.
Ancient Volcanic Eruption is to Blame
The team analyzed UV radiation levels after the supervolcano’s eruption using an advanced climate model created by NASA GISS, dubbed ModelE. The data accuracy was essential, and researchers simulated the possible aftermath of various types of eruptions.
The resulting modelling indicates that the Toba SO2 (sulfur dioxide) cloud exhausted global ozone levels by up to 50 %. Also, the team discovered that the consequences on ozone were enormous, even under small eruption cases.
The subsequent health risks from massive UV radiation at the surface would have affected the human survival rate a lot. Finally, the team compared the UV sterilization effects to the aftermath of a nuclear war. They explained that not only humans could be affected, but marine productivity and crop yields, too.
“Toba has long been posited as a cause of the bottleneck, but initial investigations into the climate variables of temperature and precipitation provided no concrete evidence of a devastating effect on humankind,” stated Sergey Osipov from the Max Planck Institute for Chemistry.
According to scientists, massive volcanic eruptions can emit many gases and ash that build a sunlight-attenuating aerosol coat in the stratosphere. That can cause Earth to significantly cool, a phenomenon known as “volcanic winter.” not
A volcanic winter is powerful enough and could lead to crop failures, cooler oceans, disease, and prolonged El Nino events. The havoc could be unimaginable, but we need better predictions to figure out some ways of preventing such disasters.