![]() ![]() “When that thaws, the water just runs off. “Half the volume of permafrost may be frozen water,” Holmes says. But rising air temperatures in the region are chipping away at this bedrock. Permafrost is like the bedrock of the Arctic (you literally need jackhammers to break it apart). “It's like pushing a knife through warm butter or something, and then you hit the bottom of the tray, and boom” - there’s your permafrost.Įventually, if you dig deep enough, the permafrost again thaws due to heat from the Earth’s core. “We have these things called thaw depth probes, which is basically just a T-bar, a steel rod that's a centimeter in diameter and 1.5 meters or so long,” Holmes says. So how do scientists know there’s permafrost underneath it? The top few inches (up to a few feet) of the permafrost is what’s known as the “active layer.” This topsoil does thaw with yearly seasonal changes, and is home to a thriving ecosystem. And a huge amount of it is frozen - permafrost rests in 25 percent of all the land area in the Northern Hemisphere. In much of the Arctic, that ground has been frozen for tens of thousands of years. The simplest definition of permafrost is ground that has been frozen for at least two years.īut it’s so much more than that. The icy mountains near Svalbard, Norway, an arctic archipelago that’s rapidly changing due to climate change. 1) Permafrost has been frozen for millennia. Because you're just like: My God, this whole thing is just going to change in a big way.” When I reached him by phone, he was in Bethel, Alaska, a small outpost town 400 miles west of Anchorage, and had just come back from an eight-day research and teaching expedition in the wilderness.Ī week earlier, Holmes and his students had set up temperature sensors in the soil near their encampment. To better understand the strange changes in the permafrost, in 2017, I spoke with Robert Max Holmes, an earth systems scientist with the Woods Hole Research Center. That would drastically change the landscape of the Arctic and potentially set off a further acceleration of global warming. In a more severe scenario where the world continues to increase emissions and we hit 5 degrees of warming, around 69 percent could be lost. ![]() Scientists: humans are rapidly turning oceans into warm, acidifying basins hostile to life Changes to the permafrost (among other changes in the ocean and cryosphere) “are expected to be irreversible,” the report states. Even if the world manages to hit the IPCC target of limiting global warming to 2 degrees Celsius by 2100, around 25 percent of the permafrost near the surface could be lost, the report finds. Permafrost temperatures keep rising, and the report paints a grim future. The UN’s Intergovernmental Panel on Climate Change on Wednesday released a 1,000-plus page report amassing all the best evidence on how the icy regions of the world and the oceans are threatened by climate change. Melting it risks accelerating global warming even further. Thawing permafrost is also a time bomb: There’s more carbon stored in the permafrost than in the atmosphere. And the retreating ice is exposing frozen plants that haven’t seen the sun in 45,000 years, as radiocarbon dating research suggests. Long-dormant microbes - some trapped in the ice for tens of thousands of years - are beginning to wake up, releasing equally ancient C02, and could potentially come to infect humans with deadly diseases. Roadways built on top of permafrost have becoming wavy roller coasters through the tundra. And things are getting weird and creepy: The ground warps, folds, and caves. It acts like a giant freezer, keeping microbes, carbon, poisonous mercury, and soil locked in place. Permafrost is a layer of frozen soil that covers 25 percent of the Northern Hemisphere. Many changes in the Arctic are ominous, and some of the most troubling are occurring beneath the surface, in the permafrost. The Greenland ice sheet is becoming unstable, and melting into the ocean at an accelerating rate. On average, Arctic sea ice extent is shrinking every summer. Our world’s northern polar region is warming twice as fast as the global average. But nowhere are the changes more dramatic than in the Arctic. You can find evidence of a changing climate everywhere on Earth. ![]()
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