From Penn State
Polar climate change may lead to ecological change
Ice and frozen ground at the North and South Poles are affected by climate change induced warming, but the consequences of thawing at each pole differ due to the geography and geology, according to a Penn State hydrologist.
“The polar regions, particularly the Arctic, are warming faster than the rest of the world,” Michael N. Gooseff, associate professor of civil and environmental engineering, told attendees today (Aug. 11) at the 96th annual meeting of the Ecological Society of America in Austin, Texas. “As a consequence, polar ecosystems respond directly to changes in the earth systems at the poles.”
These changes, though different at each pole, could be significant in their effects on not only the local environment, but also globally. While the central part of the Arctic is composed of ice over water, northern Canada, Alaska, Siberia and Greenland all have landmasses within the Arctic Circle. The associated land and water ecosystems are affected by melting ice and thawing soils, but in Antarctica, where much of the ice overlays a continent, the warming alters streams, lakes and the tiny plants and animals that live there.
“Our focus on the north is in part because it is inhabited, but it is also because the ice there is more vulnerable,” said Gooseff. “Temperatures and snow and rain across the tundra shifts annually and seasonally. We know that fall is beginning later than it once did.”
In the Arctic, where there is more immediate feedback from the higher temperatures, the warming is degrading permafrost, the layer of the ground that usually remains frozen during annual thawing events. This causes creation of a boggy, uneven landscape with a disturbed surface. Subsequent rain or snowmelt can erode this surface carrying silt and sediment into bodies of water, changing the paths of rivers and streams. Debris flows are also a common occurrence in degraded permafrost areas.
“Algae, insects and fish all must deal with this increased level of sediments,” said Gooseff.
Extended frost-free time causes soils that do thaw annually to have longer active periods when microbes can mineralize nutrients. While the soils remain frost free longer, plants continue their normal cycle dictated by the length and intensity of daylight, which has not changed. Microbes may continue to create nutrients, but the plants no longer use them, so that when rain or meltwater comes the nutrients leach into the rivers and streams.
“That is exactly what we are seeing,” said Gooseff. “In September and October, we see a substantial increase in nutrients in the water. Concentrations increase many times for nutrients such as nitrate and ammonium.”
Another problem with degrading permafrost is the release of the carbon that was permanently trapped in frozen organic materials in the frozen ground. Warming will eventually liberate carbon dioxide and methane into the atmosphere.
“It is estimated that the permafrost contains twice the amount of carbon that is currently in our atmosphere,” said Gooseff.
We think of Antarctica as a vast empty place, but lakes and streams exist in several polar desert oases, including the McMurdo Dry Valleys. These bodies of water are filled with a variety of life including microbial mats, plankton and filamentous algae.
“While there are no bugs or fish in these waters, there are diverse microbial communities,” said Gooseff. “Some algae in the dry valleys go dormant for nine months or more and then begin to grown when hit by meltwater.”
Because there is so much permanent ice in Antarctica, the annual impact of increased temperatures on its environment is slower than in the Arctic. The huge expanse of white ice reflects some of the heat energy into the atmosphere.
“We expect in the next several decades that we will see the Antarctic start to warm up,” said Gooseff.
The Antarctic permafrost is very dry with high nitrogen concentrations in some places. When water reaches some of these dry soils, it will mobilize the nutrients and increase potential habitat for freshwater aquatic communities in Antarctica. This climate change will alter the flow patterns, expand the stream networks, and change both the location of habitats and the timing of life cycles.
“Beside the information that we can obtain about climate change on Earth, understanding what happens in Antarctica is important to understand what happens on Mars,” said Gooseff. “There is potential for microbial communities on Mars, and if they exist they will probably be similar to the McMurdo Dry Valley communities.”
The National Science Foundation Office of Polar Programs supported this work.
Vince Causey says:
August 12, 2011 at 8:57 am
“It is estimated that the permafrost contains twice the amount of carbon that is currently in our atmosphere,” said Gooseff.
Reading that sentence, I’m imagining all these pieces of graphite floating around in the atmosphere.
++++++++++
Vince you are on the right track. Now, how much ‘carbon’ was in the trees that grew when that vast reservoir of ‘carbon’ was created? As soon as the permafrost starts to melt (seasonally) trees will start growing like mad. They are strange that way. By the time the ‘carbon’ emerges from the soil (putatively as methane) there will already be far more ‘carbon’ in the tree cover than there is presently in the soil. This entire permafrost-killing-us-with-methane bogeyman story is nonsense.
Now Gooseff, how much carbon in contained in the soils of the tree-covered Taiga? Come on now, is it less or more than treeless permafrost? Admit it! There’s a lot more, isn’t there! Melting permafrost will subtract huge amounts of carbon-dioxide from the atmsphere.
Bystander says:
August 12, 2011 at 10:03 am
Bystander, as always there is a mix of comments on this site. Some are reasonable, some are not. Part of the problem is that there is a misunderstanding. You seem to think that there is a “study” under discussion, and that study was “about” something.
In fact, near as I can tell it is a report, not a transcript but a report, of a speech given to a meeting of the Ecological Society of America. It does not contain a single reference or citation to anything. It is a statement of the beliefs of the person giving the speech. It’s not clear if he was interviewed, or whether the statements were taken from the speech.
As such, it is not a “study” of anything. In addition, it is almost unfalsifiable, as it does not contain a single number to quantify even one of his quoted statements. It’s all about “substantial” and “increased” and the like. And without numbers, it is scientifically meaningless. It is interesting as a statement of his beliefs, but in its present form (extracts from a speech without supporting documents or presentation slides) it is uncheckable and unfalsifiable.
So I’m not clear what kind of scientific comments you are looking for. Is the earth generally warming? Over what time period? Here’s the satellite record, I graphed the latest data just now for you:
Curiously, the north polar region didn’t warm at all from the start of the record to 1994. Since then, it is the fastest warming region on earth.
Curiously, the south polar region didn’t warm at al from the start to the end of the record. In fact it cooled slightly (but not statistically significantly).
You want science? Here’s my best scientific statement on the subject. Nobody knows why.
Oh, they’ll say they do. They’ll say its a combination of this and that, they’ll speak very knowledgeably about the matter, but there’s not a person on earth who knows why the arctic didn’t warm at all for the first fifteen years of the record, and then warmed rapidly for the fifteen years after that.
The modelers will assure you that their model knows why, or at least that if you take an average of thirty unranked models and squint at it from across the room it will look kind of like what happened. Or they’ll come out with my favorite, “natural variations”, as though giving it a name explained it.
But nobody knows why that happened. And more to the point, no one knows what it will do for the next fifteen years.
Nor do we have an explanation for the contemporaneous thirty-year temperature stability of the Antarctic. The good doctor assures us that he expects it to start warming in the near future … based on what? The best record we have shows no warming at all while the rest of the world has been warming. On what basis is he claiming that it will suddenly act differently? It may do so, to be sure, but asserting that it will do so has no historical basis.
Our lack of knowledge of what we term “natural variations”, which really means the subject of the inner workings of the planetary-scale heat engine we call the climate, is staggering. If more climate scientists would learn do say “we don’t know”, we’d be a lot better off.
That’s my read on the questions of the Arctic and Antarctic … but I’m just back from a week in Alaska, so I could be wrong. The place always messes with my mind, something to do with only a few hours darkness plus the intoxicating smell of damp rich vibrant northern forests, where every plant is hurrying and counting the days until winter …
My best to all,
w.
It’s a crying shame that all the funding provided by the NSF to UAF-GI for northern hemisphere permafrost depletion studies doesn’t allow their findings to be disseminated to the world.
The reports I’ve seen show that the depletion came to an end in 2005 with further temperature decreases since then. Good portions of the continuous and discontinuous permafrost regions get very close to 32 degrees F. and the ice lenses contained within the layers do provide rapid surface changes when they melt (thermokarsts, oblique depressions etc..), but I suspect that over the next two years the alarmists will need to change their tune, as the temperatures continue their drive downwards.
Cheers:)
“The polar regions, particularly the Arctic, are warming faster than the rest of the world,”
Even if this statement were true it does not necessarily follow that the temperature change in the Arctic has anything to do with manmade CO2 emissions. No science here. They are drawing a long bow.
Penn State continues to be embarrassed by the low quality of their faculty.
N.C.;
Do you see any evidence of Penn State embarrassment? If Mann is a measure of the place, it’s quite shameless. Defiantly so, in fact.
Willis, don’t know if you caught it, but our mutual good friend cementovershoes (or SLT 😉 ) posted an excellent demolition of the standard meme(s) about methane here.
Super-short version: methane is being ‘credited’ with the IR footprint of its burn product, H2O, and actually washes out of the air as methanol after reacting with O3.
It’s harmless, and a complete squib as a GHG.
Brian H says:
August 12, 2011 at 6:58 pm
Brian H, it seems totally simplistic. Methane photochemistry is very complex, see here.
w.
Obviously a strong contender for the B.S. Johnson lifetime achievement award. Competition for the accolade is fierce. Monnett, Gore and Mann have also been nominated.
But from the article, this “The absorption due to the 7.4 p band of methane increases linearly with CH4 concentration up to a mixing ratio of about 0.7 ppm, then more slowly above this level as the center of the band becomes saturated,” seems to be the core problem and misrepresentation.
Take a look at the methane 7.4p band in the Cement posting. It’s a trivial notch compared either to CO2 or H2O. No way is it “21X” as potent as CO2. If anything, closer to the inverse of that ratio.
Olen says:
August 12, 2011 at 1:53 pm
It is thinking like this that happens when you do it with virtual models instead of live ones.
and in isolation.
When I lived in Alaska, I managed building construction projects at Barrow, AK. I took a course in Arctic Engineering. We studied permafrost. Permafrost is defined as any material that has been contineously frozen for two or more years. Under that definination, solid rock is considered to be permafrost. Likewise peat moss and tundra, BELOW THE ACTIVE LAYER, are also considered to be permafrost. The active layer freezes and thaws with the seasons. The depth of the active layer depends upon the latitude, southern or northern exposures, vegetation and the nature of the soil. At Barrow, Ak. the active layer is anywhere from two to three feet thick. So, did this study actually measure, over some period of time, the actual depths of the active layer? Or did Professor Gooseff simply travel to the Arctic and observe the typical summer mud flats and bogs of the North Slope and simply opine that the permafrost is melting?
Dave Bufalo
Licensed Professional Civil Engineer