The impact on the climate may mean an influx of permafrost-derived a ten-year program to understand climate change effects on the Arctic. The major side effect of a thawing permafrost is that it will further enhance global warming with the release of large quantities of methane. The world is on course to exceed global warming limits set out in the Paris climate the first comprehensive study of the impact of melting permafrost. about climate change based on a “linear relationship” between global.
Melting Permafrost | Weather Underground
Unfortunately, when permafrost warms and thaws, it releases carbon dioxide and methane into the atmosphere. As the global thermostat rises, permafrost, rather than storing carbon, could become a significant source of planet-heating emissions. NPS Climate Change Response Permafrost is already thawing in some placesand if the problem spreads, scientists worry it could initiate a runaway process of global warming.
The Warming Arctic Permafrost covers about 24 percent of the exposed landmass of the Northern Hemisphere—about 9 million square miles.
The continental shelves below the Arctic Ocean, which were exposed during the last ice age, also contain permafrost. However, polar and high altitude regions are some the most climate-sensitive places on the planet. The Arctic is warming twice as fast as the rest of the planet, at a rate of temperature change that has not been observed in at least the last 2, years, according to the National Oceanic and Atmospheric Administration NOAA. Inannual average surface temperatures were 3. That year, permafrost temperatures in the Arctic were the warmest ever recorded.
When Permafrost Thaws O. Coastal erosion reveals permafrost underlying the active layer in Alaska. This layer releases carbon from the roots of plants that respire out CO2, and from microbes in the soil. Some microbes break down the organic matter into CO2. Others, called archaea, produce methane instead, when conditions are anaerobic—when the soil is saturated with water or no oxygen is available. Methane is 20 to 30 times more potent than carbon dioxide at exacerbating global warming, but it remains in the atmosphere for less time.
As permafrost thaws, the active layer deepens. The microbes become active and plant roots can penetrate further down, resulting in the production of more CO2. The amount of methane generated depends on how saturated the ground is.
However, research on the upper layer of the tundra treeless plains overlying the permafrost suggests that the average carbon dioxide emissions are about 50 times higher than those of methane. A study estimated that if global temperatures rise 1.
Without factoring in human activity, this carbon alone would increase global temperatures 0. Since we may have already locked in 1. What Protects Permafrost One thing that protects permafrost from the impacts of climate change is peat, the partly decayed vegetation that accumulates in water-saturated environments with no oxygen.
Found in much of the low Arctic, peat can overlie or encompass the whole active layer or be frozen as permafrost.
Why Thawing Permafrost Matters
Peat on the tundra. Ben Gaglioti Ben Gaglioti, a postdoctoral research scientist at Lamont-Doherty Earth Observatory, studied lake sediment records in northern Alaska to determine how much carbon the permafrost released in response to warming periods at the end of the last ice age. It turns out that the permafrost was much more sensitive—meaning it released more carbon—during past warming events, with gradually less response over time.
In the most recent years of warming, there has been relatively little response.
Warmer and drier summers make vegetation more combustible. Warmer temperatures also bring about more thunderstorms and lightning strikes that can spark wildfires.
Fire near Ivotuk, AK. Ben Gaglioti Fires not only release CO2 as they burn; afterwards, the blackened ground absorbs more solar radiation and warms further.The Crazy Solution For Keeping The Melting Arctic Frozen - VICE on HBO
And once fire removes the peat and vegetation that shades the ground, the landscape can become too well-drained to regenerate the peat. Many scientists are concerned that thawing permafrost could be a tipping point that triggers an irreversible cycle: When permafrost releases its carbon as CO2 or methane, it will accelerate warming, which will then precipitate more permafrost thaw, and so on.
As the active layer thaws, some organic matter decomposes. Under normal climate conditions i. But as air temperature increases and the ground warms, this process will speed up, and scientists think this could begin very soon. Some suggest the arctic tundra could go from being a carbon sink to a carbon source by the mids.
This amount is about half of all the carbon released in the industrial age.
The affect this will have on the rate of atmospheric warming could be irreversible. At the very least, these estimates mean fossil fuel emissions will have to be reduced more than currently suggested to account for the amount of carbon expected to discharge from melting permafrost.
Peatlands are also expected to be impacted by global climate change. Peat is made up of dead organic material, and so is very rich in carbon. Some of this peat is found underneath the permafrost layer, which means the carbon it harbors could be in jeopardy should the permafrost melt.
In moist areas, most of the emissions will be of methane, a greenhouse gas that has 20 to 25 times more warming power than carbon dioxide. As the ground warms, methane will either be released directly into the atmosphere or bacteria will break it down into carbon dioxide, which will then be released. If areas of thawed permafrost exist at depth between frozen layers, it's possible that microbial activities will continue unabated, even during the winter, to create new methane from organic material.
This is what is believed to be happening around Siberia's lakes. Inresearchers working at two northern Siberian lakes found that methane was bubbling up from thawing permafrost at a rate five times faster than originally thought. The study also found an expansion of "thaw lakes" in the permafrost regions. Studies conducted in Canadian and Swedish permafrost and peatland regions also show these trends.
Permafrost: a climate time bomb?
Methane hydrates can be thought of as methane gas frozen into ice structures, like the one in Figure 5. They're formed at cold temperatures and under high pressure—conditions that are both present beneath layers of frozen permafrost.
The amount of methane hydrates in permafrost could range anywhere from 7. Methane hydrates are abundantly present in and near the Siberian Ice Complex, or Arctic Shelf, which provides a shelf-like structure to support the land and coastline on top of it.
As waters along the northern coast warm, the ice complex melts, allowing for quick erosion compared to the historical rate. And recent research shows the amount of methane currently being released from the Arctic Shelf region is around the same amount of methane being released from all the oceans in the world.
This is particularly dangerous because of the Shelf's shallow depth. In other regions where methane hydrates exist, they are deep enough to oxidize to carbon dioxide before reaching the surface.
Permafrost In a Warming World
In this region, the methane is released directly into the air. University of Alaska Fairbanks Professor Katey Walter Anthony takes us onto a frozen lake in Fairbanks, AK to demonstrate why methane gas has "exploded" onto the climate change scene. Structure of a gas hydrate methane clathrate block. The Disaster Scenario It's not hard to imagine a disaster scenario surrounding permafrost.
As the atmosphere warms, permafrost melts, which releases greenhouse gas, which further warms the atmosphere, which speeds up the permafrost melting, and so on. Currently, climate models do not incorporate the effects of methane released from melting permafrost, which means even the most extreme warming scenarios we've come up with might not be extreme enough.