Scientists found that during ice ages, sea levels were lower and thus underwater volcanoes could expel more lava as well as carbon dioxide, which may have warmed the Earth.
A new study suggests that underwater volcanoes may have a significant impact on the climate, pumping out huge volumes of carbon dioxide gas that could alter temperatures on the planet.
Volcanic chains cover 37,000 miles of ocean floor, and scientists are finding that these volcanoes could have a big impact on the climate cycle, according to the lead author of the study, Maya Tolstoy, who is a marine geophysicist at the Lamont-Doherty Earth Observatory in Palisades, N.Y., as reported by the Christian Science Monitor.
The volcanic chains create new oceanic crust called spreading ridges, which is when magma rises to fill the gap between the constantly shifting tectonic plates. As the plates pull away from these ridges, the newly formed crust cools and then cranks and sinks, causing gaps between the volcanoes, creating features on the Earth’s floor that are unmistakable.
The study centered on the East Pacific Rise spreading ridge found near western South America. It found a connection between ice age cycles and the ridges, a relationship that is 800,000 years old, with the crust features matching 100,000-year ice age cycles. Basically, when the sea level dropped during ice ages because of more glacier formation, the ridge volcanoes expelled more lava, creating a thicker crust. During warmer times, the sea level was higher, causing crust formation to slow and create a thinner crust.
Another study was conducted on the gap between Australia and Antarctic tectonic plates, and researchers found similar results.
What does this mean for the climate? The studies suggest that if volcanoes increase in magma expulsion during low sea levels during an ice age, it will also result in an increase in carbon dioxide from volcanic activity that could warm the Earth and cause ice sheets to shrink, although it is unknown how much gas could escape from the oceans into the atmosphere.
The data suggests that the “climate system and the solid Earth are connected and, in fact, may be thought of as a single system,” said Richard Katz, who co-authored the other study and works as a geophysicist at the University of Oxford.
Tolstoy’s findings were published in the journal Geophysical Research Letters. Katz’s study was published in the journal Science.
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