Is Permafrost Really, Well, Permanent?

Advertisement

Advertisement

In 2010, a woolly mammoth carcass was discovered in Siberia near the coast of the Laptev Sea. Nicknamed “Yuka,” the long-extinct beast died around 28,000 years ago. Yet her body was astonishingly well-preserved, complete with patches of reddened fur, a brain that was largely intact and nucleus-like cell structures.

How did her corpse last this long without rotting away? The short answer is, Yuka was frozen — but not inside some glacier or iceberg. After death, Yuka became encased in a layer of what’s known as http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html.

As we know, water freezes at 32 degrees Fahrenheit (0 degrees Celsius). Permafrost is any ground material — such as soil, sediment and rock — that remains at or below freezing temperatures for at least two consecutive years. About 25 percent of all the land area in the Northern Hemisphere is known to contain http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html.

It was American paleontologist Siemon W. Muller who originally coined the term “http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html,” a portmanteaux of the words “permanent” and “frost.” Despite that name, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html doesn’t last forever. Thanks to climate change, it’s been thawing in large quantities. This has serious ramifications for both the environment and the economy.

Generally speaking, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html tends to occur in places where the average air temperature is 0° Celsius (32° degrees Fahrenheit) or lower every year. According to the National Snow and Ice Data Center, most of the Northern Hemisphere’s http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html sits between the high latitudes of 60 and 68 degrees north. Siberia, Canada, Alaska and parts of Scandinavia are loaded with this frigid turf.

Further south, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html tends to be found in high-elevation areas — like the Tibetan Plateau, the Hindu-Kush Mountain Range and the Swiss Alps. Permafrost isn’t as widespread below the equator, but it does underlie parts of New Zealand, the Andes Mountains and Antarctica.

Just as its locations vary, so does its composition; it’s not uniform. Some section are ice-free, while others are made up of more than 30 percent ice. Likewise, the depth, age and extent of http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html can vary widely.

Oftentimes, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html sits beneath an “active layer” of ground, which thaws and re-freezes seasonally. The http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html itself can measure anywhere from less than 3.2 feet (1 meter) thick to more than 4,921 feet (1,500 meters) thick.

And it can get patchy. Northern Alaska occupies a “continuous http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html zone.” That means http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html underlies more than 90 percent of the local terrain. But at lower latitudes it’s a different story. Pretty much everything south of the Brooks Mountain Range sits in a “discontinuous http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html zone.” Here, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html resides under a smaller percentage of the land’s surface.

Counterintuitive as it sounds, snow is a really good insulator. So when thick blankets of it stick around all year long, they might keep the ground too warm for http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html. Likewise, in spots where http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html already exists, insulating layers of surface-level snow are liable to heat it up.

But while snow’s an impediment, peat is a boon. Widespread in and around the southern Arctic, peat is a kind of substrate that’s made of partially decayed organic matter (e.g. mosses and swamp plants). By and large, the ground beneath it is kept cool, shielded from solar heat. Thus, peat safeguards http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html.

Evergreen forests lend a helping hand, too. With their thickly needled branches, pine trees limit the amount of sunlight and snow that hits the ground’s surface. In the process, the evergreens help keep http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html from thawing. So it’s no wonder that http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html is common below the clustered pines in high-elevation and high-altitude areas.

The arrangement is mutually beneficial. Since liquid water can’t seep through hard http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html, it acts like a drainage barrier. Unfrozen water that’s absorbed into the active layer gets trapped there. Barred from traveling deeper into the earth, this water sustains some of the plants that live at the surface.

Sometimes, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html forms in concert with the ground itself. When this happens, the temperature of newly deposited soils, sediments and rocks hits 32 degrees Fahrenheit (0 degrees Celsius) very quickly. On the other hand, http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html can also develop when an existing sample of un-frozen ground is chilled from the surface level downward.

At minimum, the http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html in Prudhoe Bay, Alaska is thought to be 500,000 years of age. And some of the http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html beneath Canada’s Yukon Territory could be more than 700,000 years old.

Inside the latter, scientists found an ancient horse leg — complete with DNA samples. Permafrost can keep all kinds of organic matter preserved over long periods of time. In 2012, Russian scientists actually regenerated live tundra plants from ice age fruits that had been encased in http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html for about 30,000 years.

Unfortunately, as http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html thaws, that trapped organic material decomposes, releasing carbon and methane into the atmosphere. Those gasses exacerbate climate change. And the bad news is, according to a 2019 study published in Nature Communications, various http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html deposits around the world have warmed up by about 39.7 to 32.8 degrees Fahrenheit (0.39 to 0.1 degrees Celsius) between the years 2007 and 2016.

Right now, approximately 1.7 billion tons (1.6 billion metric tons) of carbon is trapped in http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html. Scientists don’t know how much of this will be released into the atmosphere if current thawing trends continue — or how quickly it’ll escape. But some projections are not encouraging.

To make matters worse, when http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html thaws, it can destabilize the landscape. In the city of Norilsk, Russia alone, more than 100 residential buildings have been damaged because the once-solid http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html beneath them is softening. The warming of http://peterupdraft:8888/wp-content/uploads/2020/01/permafrost.html has also triggered landslides, drained lakes and torn roads apart.

Print |
Citation & Date |
Reprint

Health · Previous Story

Next Story · Entertainment

Advertisement

Advertisement

Advertisement

Advertisement

Advertisement

Climate Change Could Destroy Doomsday Vault

Arctic World Archive Puts Data on Ice for 1,000 Years

Why is Arctic ice melting 50 years too fast?

Advertisement

How the Boston Massacre Fanned the Flames of a Revolution

January 6, 2020

The Tiny Fennec Fox Is All Ears

January 6, 2020

What’s the Difference Between an Avenue, a Road and a Boulevard?

January 3, 2020

Advertisement

Advertisement

Advertisement

Get the best of HowStuffWorks by email!

Keep up to date on: Latest Buzz · Stuff Shows & Podcasts · Tours · Weird & Wacky

Copyright © 2020 HowStuffWorks, a division of InfoSpace Holdings, LLC, a System1 Company

Is Permafrost Really, Well, Permanent?

Research & References of Is Permafrost Really, Well, Permanent?|A&C Accounting And Tax Services
Source

Share on Facebook

Tweet

Follow us