Ninety-eight percent of the frigid continent is covered by ice, which is almost on an average 1.1 miles thick. Despite the difficulties to study the ice floor of the continent, scientists have revealed something startling.
If you think Antarctica is full of only ice, you may have to rethink. There is a lot of fire beneath the ice sheets of the continent. It is home to a number of extinct and active volcanoes.
Recently, scientists discovered 91 new volcanoes in Antarctica, adding to the already identified 47 volcanoes. What worries the scientists is the amount of melting these volcanoes could cause, when they erupt.
A few geologists from University of Edinburgh conducted the study. The analysis of the West Antarctic Rift System identified 178 cone like formations beneath the floor, out of which 138 tuned out to be volcanoes.
Their heights vary from 100 to 3850 meters, Some of them are covered 4 km deep inside the ice. These 138 volcanoes make the West Antarctica stretch the volcano-densest regions on earth, beating Africa, which obviously now becomes the second volcano-densest region. In the West Antarctica, there is one volcano per every 4800 square miles.
The data revealed explains only the physical features of the volcanoes and not their geo-thermal activity. Hence, it is not clear to scientists how active these volcanoes are.
Even though, none of the volcanoes are responsible for the melting of ice currently in Antarctica, scientists say that the current melting of ice at the top of the active volcanoes may cause them to erupt- if they have an over-pressurized magma chamber- leading to further melting of ice.
In the past, in Iceland, melting of ice have caused volcanic eruption resulting in increased melting creating a positive feedback loop. Melting of ice sheets due to these volcanoes could destabilize the continent’s floor, causing a rift.
This rift could result in more volcanic eruption. Also the flow of ice in to the ocean will also be increased. To make things worse, the two regions of the continent, east and west Antarctica are moving away at a rate of 2mm per year.
However,there is also a contradicting view that these volcanoes could act as pin points holding the ice from reaching the ocean. A lot depends on how smooth is the surface beneath the ice.
If the ice bed beneath is rough with craters and volcanic cones, the rate of ice receding into the ocean could be minimized, says John Cottle, professor, University of California, Santa Barbara.
Mount Sidley is the so-far known highest volcano, but dormant in the continent. Mount Erebus, also the southern-most active volcano on earth, is the second highest in Antarctica, which has been active since 1.3 million years. Mount Erebus erupted last in 2015.
The lava lake at the summit of Mount Erebus is one among earth’s five long-lasting lava lakes.
Along with it, Deception Island is the only other active volcano in Antarctica, making the count two. Mount Erebus has been spewing magma in the last decade, but the much smaller Deception Island has created the largest known volcanic eruption in Antarctica.
UK, Argentina and Chile set up their observatories to monitor the Deception island, yet two of its eruptions in 1967 and 1969 were not predicted. During its eruption, scientists expected the thin sheet of glacier to become steam when lava erupts. But things went different.
The volcano erupted huge amount of mud destructing the UK and Chilean observatories. Now, the Spanish and Argentine stations remain. Even though, the states of volcanoes are yet unclear and also their consequences, what is obvious to our eyes are these 138 volcanoes.
Also, the research looked for cone-shaped formations beneath the ice and there could be many other forms of volcanoes, The geo-thermal patterns of the volcanoes were also not studied during this research.
What could one say with certainty is that there are more things awaiting to be uncovered in the ice-filled continent.
Image Source: National Geographic