“Snowball Earth” Receives A New Explanation From Scientists

“Snowball Earth” is the name given to the largest glaciation event to have ever hit our planet. But science was uncertain what caused such an extreme phenomenon. Now, a paper argues that it may have developed thanks to a “perfect storm or ice and fire”.

What Is The Sturtian Snowball Earth?

Some 717 million years ago, our planet was a very different place. Science determined that, at the time, the planet was covered in ice. During its 4.5 billion years, Earth passed through some quite extreme climatic cycles.

• Snowball Earth is considered the as yet coldest global climate period on Earth.
• It took place over 700 million years ago.
• Temperatures were so extreme that the planet was frozen over for at least 5 million years.
• The event set in about 717 million years ago, give or take 100,000 years.
• Around that same period, a huge volcanic event may have taken place.

This devastated a vast area in between present-day Alaska and Greenland. According to a new study, this also led to the snowball Earth. Research was carried out by two Harvard University researchers, Robin Wordsworth and Francis Macdonald. They are both part of SEAS or the John A. Paulson School of Engineering and Applied Sciences.

The study is called: “Initiation of Snowball Earth with volcanic sulfur aerosol emissions”. It was published in the Geophysical Research Letters journal.

Snowball Earth Caused By “A Perfect Storm of Fire And Ice”?

The researchers offered Earth’s intense volcanic activity as the reason behind its extreme glaciation. This “once-in-a-billion-year event” may have been caused by two intrinsically related phenomena. Research already knows that volcanic activity can impact the environment. Depending on the magnitude of the event, the effects can also be quite significant.

At the time, the volcanic activity spanned over around 2,000 miles. These volcanoes were erupting almost continuously. Which also led to massive releases of aerosols. These started accumulating in the atmosphere. One such product, sulfur dioxide, is very efficient at blocking solar radiation. Especially so as it reaches upper atmospheric layers.

The increased volcanic activity increased sulfur dioxide levels. As they started accumulating, they may have led to a significant destabilization of Earth’s climate. Ice may have started forming as the volcanoes were still erupting.

This happened as the planet was already cooling down. The ice and fire dance may have continued this process until it reached a critical point. As it crossed this line, ice took over and led to snowball Earth. Wordsworth pointed out our planet’s active and dynamic place. He also drew attention to its sharp transitions between states.

Wordsworth also stated that “There is every reason to believe that rapid climate transitions of this type are the norm on planets, rather than the exception”.

This potential explanation of snowball Earth may also have a larger application. According to the researchers, it may also apply to the present-day climate and aerosol perturbations. Also, it may help better determine exoplanet habitability.

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