Daily VideoAugust 21, 2014
Mystery holes in Siberia raise climate change concerns
A new side effect of climate change has appeared in Siberia, where mysterious, giant holes the size of football fields have opened in the ground.
Scientists were surprised by the holes and initially thought the cause was an underground gas explosion, according to Tom Wagner, who studies polar regions for NASA.
The Arctic’s top ground layer is largely permafrost — frozen soil and rock that releases methane gas when it melts. Experts originally thought that as the permafrost melted in recent years, so much gas was released underground that it broke through to the surface, forming the holes.
A more likely theory, Wagner said, is that the holes are actually giant sinkholes that formed when the Arctic melting released water that eroded underground layers of rock. This process created large cavernous spaces just beneath the surface of the earth, making the top layer vulnerable to collapsing.
And with the Arctic melting more quickly than ever before, these sinkholes are appearing on a larger scale than scientists have ever seen, Wagner said.
Another danger of melting permafrost: it could release carbon and methane into the atmosphere, which would increase the rate at which the atmosphere warms. Studies show that rainfall and flooding are already set to increase in the future in some parts of the world, and this change in the atmosphere would also affect weather patterns.
It is very challenging for scientists to travel to the Arctic to do the research they need on climate change.
“The permafrost and the Arctic in general is this fantastic record of science and changes our planet went through in the past. But going and working there is profoundly difficult,” Wagner said.
Warm up questions
- Where is the Arctic? Where is Siberia?
- What is the difference between a theory and a scientific theory?
- What are some examples of climate change that you see in your own community? In the United States? Globally?
Critical thinking questions
- Outline the theory that scientists now believe explains the growing number of sinkholes. What are the strengths and weaknesses of this scientific theory? How can it be tested?
- Why might it be dangerous to release larger quantities (compared to the previous 1000 years) of chemicals like carbon and methane into the air? What are the consequences?
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