Researchers have found that climate change may cause Iceland’s glacial volcanoes to erupt more often in the future.
A volcano erupting from underneath the Eyjafjallajokull glacier emits a plume of smoke.
We’ve known for quite a while that climate change can do quite a number on us, especially as temperatures rise higher and higher as time goes on. Scientists are now finding more and more ways that climate change will affect the planet—and us—in the future.
One such possible impact is the higher frequency of volcanic eruptions in the following centuries, particularly among the glacier-covered volcanoes of Iceland. A recent study shows that as glaciers melt due to rising temperatures, Icelandic volcanoes may start waking up and erupting more frequently. This is because glaciers may have something to do with the interaction between rifts in continental plates and the pressure of gas and magma within the volcanoes. It’s highly possible that the changes that occur in aboveground glaciers may affect the volcanic activity that occurs underground.
Volcanic ash from the Grimsvotn volcanic eruption covers a icebergs in a glacial lagoon. [Photo by Reuters]
The researchers analyzed peat deposits and lake sediments that preserved volcanic ash, basically looking into a window of volcanic history. Their investigations revealed a period of time about 5,000 years ago which led to a time of less volcanic activity. This period of volcanic slumber happened to coincide with a decrease in the global temperature.
According to the study’s findings, the glaciers that formed during that time period of low temperatures likely caused the volcanoes to become less active. It therefore follows that because glaciers are melting due to manmade climate change, the volcanoes might begin waking up.
The underground pressure from gas and magma build-up interacts with the continental plates sitting above them. This interaction, however, can be altered by changes that occur aboveground—changes that include glacial melt.
A period of cooler climate, called “Little Ice Age”, affected Iceland’s volcanoes between the years 1500 and 1850. In more recent times, however, the rapid increase in temperature and the decrease in glaciers have also caused a decrease in the aboveground pressure on our continental plates.
“This can increase the amount of mantle melt as well as affect magma flow and how much magma the crust can hold,” says Ivan Savov, one of the researchers. “Even small changes in surface pressure can alter the likelihood of eruptions at ice-covered volcanoes.”
Bardarbunga, a central Icelandic volcano, erupts from underneath the Vatnajokull glacier.
Dickinson College earth sciences professor Ben Edwards, who wasn’t involved in the study, says that the glacial ice in Iceland is actually not as thick as glacial ice in places like Greenland and Antarctica. Therefore, while the melting Icelandic glaciers may have an impact on volcanic activity, that impact may not be as significant or substantial as expected.
Also, it may take a few hundred years before the volcanic eruptions begin to become more frequent. The study found that it took 600 years for there to be fewer volcanic eruptions after the period of lower temperatures that occurred 5,000 years ago. Thus, the same could be true for volcanic eruptions to become more frequent again after a period of higher global temperatures.
The researchers stress that this is why climate change conferences are important. This way, we can understand how manmade climate change can impact our future generations.
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