Alaska is getting wetter. That’s bad news for permafrost and the climate

UNIVERSITY OF COLORADO AT BOULDER

IMAGE
IMAGE: POSTDOCTORAL FELLOW CATHERINE DIELEMEN ASSOCIATED WITH MERRITT TURETSKY’S RESEARCH GROUP USES A FROST PROBE TO DETERMINE THE LOCATION OF SURFACE PERMAFROST BENEATH THE GROUND SURFACE IN INTERIOR ALASKA. view more CREDIT: MERRITT TURETSKY

Alaska is getting wetter. A new study spells out what that means for the permafrost that underlies about 85% of the state, and the consequences for Earth’s global climate.

The study, published today in Nature Publishing Group journal Climate and Atmospheric Science, is the first to compare how rainfall is affecting permafrost thaw across time, space, and a variety of ecosystems. It shows that increased summer rainfall is degrading permafrost across the state.

As Siberia remains in the headlines for record-setting heat waves and wildfires, Alaska is experiencing the rainiest five years in its century-long meteorological record. Extreme weather on both ends of the spectrum–hot and dry versus cool and wet–are driven by an aspect of climate change called Arctic amplification. As the earth warms, temperatures in the Arctic rise faster than the global average.

While the physical basis of Arctic amplification is well understood, it is less known how it will affect the permafrost that underlies about a quarter of the Northern Hemisphere, including most of Alaska. Permafrost locks about twice the carbon that is currently in the atmosphere into long-term storage and supports Northern infrastructure like roads and buildings; so understanding how a changing climate will affect it is crucial for both people living in the Arctic and those in lower latitudes.

“In our research area the winter has lost almost three weeks to summer,” says study lead author and Fairbanks resident Thomas A. Douglas, who is a scientist with the U.S. Army Cold Regions Research and Engineering Laboratory. “This, along with more rainstorms, means far more wet precipitation is falling every summer.”

Over the course of five years, the research team took 2750 measurements of how far below the land’s surface permafrost had thawed by the end of summer across a wide range of environments near Fairbanks, Alaska. The five-year period included two summers with average precipitation, one that was a little drier than usual, and the top and third wettest summers on record. Differences in annual rainfall were clearly imprinted in the amount of permafrost thaw.

More rainfall led to deeper thaw across all sites. After the wettest summer in 2014, permafrost didn’t freeze back to previous levels even after subsequent summers were drier. Wetlands and disturbed sites, like trail crossings and clearings, showed the most thaw. Tussock tundra, with its deep soils and covering of tufted grasses, has been found to provide the most ecosystem protection of permafrost. While permafrost was frozen closest to the surface in tussock tundra, it experienced the greatest relative increase in the depth of thaw in response to rainfall, possibly because water could pool on the flat surface. Forests, especially spruce forests with thick sphagnum moss layers, were the most resistant to permafrost thaw. Charlie Koven, an Earth system modeler with the Lawrence Berkeley National Laboratory, used the field measurements to build a heat balance model that allowed the team to better understand how rain was driving heat down into the permafrost ground.

The study demonstrates how land cover types govern relationships between summer rainfall and permafrost thaw. As Alaska becomes warmer and wetter, vegetation cover is projected to change and wildfires will disturb larger swathes of the landscape. Those conditions may lead to a feedback loop between more permafrost thaw and wetter summers.

In the meantime, rainfall–and the research–continue. Douglas says, “I was just at one of our field sites and you need hip waders to get to areas that used to be dry or only ankle deep with water. It is extremely wet out there. So far this year we have almost double the precipitation of a typical year.”

“This study adds to the growing body of knowledge about how extreme weather–ranging from heat spells to intense summer rains–can disrupt foundational aspects of Arctic ecosystems,” says Merritt Turetsky, Director of the University of Colorado Boulder’s Institute of Arctic and Alpine Research (INSTAAR) and a coauthor of the study. “These changes are not occurring gradually over decades or lifetimes; we are watching them occur over mere months to years.”

###

From EurekAlert!

80 thoughts on “Alaska is getting wetter. That’s bad news for permafrost and the climate

  1. “Wet precipitation”?
    Rather than dry precipitation?
    Obviously worse than we thunk.

    • Martin Howard Keith Brumby July 26, 2020 at 10:19 pm
      “Wet precipitation”? Rather than dry precipitation?

      It’s much more “sciency” than merely saying rain or snow.

    • hot and dry at the same time as cool and wet in the Arctic. Dont these researchers ever ‘get’ irony. With those 2 parameters alone appearing at the same time surely they can see what B/s making a climate prediction like this is!

      • Oh nonsense Mark. Everyone knows that the Roman Warm Period was only in Rome. Probably only on one side of the Tiber river. In a small neighborhood. Just ask any troll.

        I think I remember mosh telling us it was caused by changes in Roman pollution control regulations that caused a sudden drop in aerosols. Don’t quote me on that. It might have been griff.

        • I think their SUV-sized chariots had something to do with it too – you know, the big ones with eight farting horses.

    • They are looking at the only real time frame that matters. The last 100 years. Well, the only time frame that matters to them.

  2. Alaska is a big state. All of 65% with permafrost is “getting wetter”…All, not 90%, 60% or something else?

    • NOAA says There has been no long-term trend showing any increase in precipitation in Alaska.

      There was an increase in summer rain for four years which might coincide with the study.

      But the fact that one of the authors points to month to month events and multi-year changes as *evidence* in FAVOR of climate change pretty much puts her in the category of frothing at the mouth alarmism…

      NOAA

      “ Average annual precipitation amounts vary greatly across Alaska. Coastal mountain ranges in the southeastern panhandle receive more than 200 inches per year, while totals drop to 60 inches south of the Alaska Range, 12 inches in the interior, and less than 6 inches in the North Slope. The record amount of rainfall to occur in a 24-hour period was 15.05 inches at Seward in southcentral Alaska in October 1986. The record maximum snowfall in a 24-hour period was 78 inches on February 9,1963 at Mile 47 Camp along Highway 4 in the southeastern portion of the state. The driest multi-year periods were in the 1950s and late 1960s/early 1970s, and the wettest period was in the late 1920s (Figure 5). The driest 5-year period was 1968-1972 and the wettest was 1928-1932. Since the late 1980s, total annual precipitation in Alaska has been above the long-term average except for a dry period in the late 1990s. There is considerable regional variability, however, as portions of interior and Arctic Alaska have observed a long-term decrease in precipitation. Also, for the summer season, the latest 5-year period (2010–2014) is the wettest on record (Figure 3c). As with average precipitation, the occurrence of extreme precipitation events is highly variable and is both regionally and seasonally dependent. Most of Alaska has seen an increase in extreme precipitation events (the heaviest one percent of 3-day precipitation totals) since the mid-20th century; however, there is no statewide average trend in the number of days with precipitation exceeding 1 inch since 1950, and the highest values occurred in the 1930s.”

  3. Damn those SUVs!!! We need to go back to bicycles like the Younger Dryas did after the Neanderthals brought on the great ice age with their excesses.

    Just like scientist Dennis Quaid said in the future documentary “The Day After Tomorrow”, “When will we ever learn!”

  4. Geez, a few years of wet weather and now predictions that all the permafrost will melt. It’a been a real cold, wet spring and summer so far in BC too until today. Just weather. Actually, all of Canada and much of northern USA was also deep permafrost, where it isn’t shield rock for about 100,000 years under a mile or two of ice and much of that permafrost melted without any issue. Probably added a few points to the CO2 score. which enabled life to flourish on the good Earth.

    Actually the melting of the permafrost would be a good thing, as then vegetation could really grow deep roots and new bigger forests. There would be a one-off methane release, which turns to CO2 mostly within a dozen years or so. Orders of magnitude more ‘carbon’ would be locked up for the next 100-200 years than any adverse effect from the one time Methane release. Why don’t they tell the other side of the story? Or am I not thinking correctly?

  5. If they are talking about precipitation in Alaska, then surely that means that the temperatures have been pretty average over there. Otherwise the focus would be in the temperatures.

  6. Melting permafrost makes gold digging more profitable and viable, so maybe it is time to move to Alaska to dig for gold.

    • Have you not watched the Gold Rush TV Series?
      They are already in Alaska during the non frozen season, taking out Millions in Gold.

      • Yes, great series in which it was obvious that the diggers gave up several places as they hit permafrost.
        On another, but related, note Denmark is still paying the cost of maintaining Greenland. In my view they mainly do so, because Denmark hope to earn on the minerals in Greenland, as advances in technique makes mining there more viable.

        • No wonder DJT wanted to buy it for the USA. You’d think our POTUS was a savvy business man. 😁

  7. ‘While the physical basis of Arctic amplification is well understood’ -is written – OK – so my question is – explain this well understood physical basis of Arctic amplification and then it’s written;

    ‘Permafrost locks about twice the carbon that is currently in the atmosphere into long-term storage and supports Northern infrastructure like roads and buildings;’ – all in one sentence – seriously?

    OK so how do they know and then measure that permafrost locks about 2X the carbon that is now in the atmosphere???

    and this long term carbon storage apparently supports Northern infrastructure like roads and buildings ???

    what this sentence is non-sensical

    • Claim:‘While the physical basis of Arctic amplification is well understood’.
      Science:”The precise mechanisms driving Arctic amplification are still under debate.”
      Source: https://eartharxiv.org/dzmvq/ .
      It’s a preprint, however it summarises the state of knowledge pretty good.
      What to say about the paper in question? Overconfidence at least.

    • There is carbon frozen within the ice. What’s nonsensical about that?
      The fact that many buildings and roads rest on this ice is also well known. Having buildings sink when the permafrost under them melts is a well known problem in the region.

      • Usually it is the building itself, or the highway/road, that causes more ground heat retention as in the case under a building. Even a building on stilts affects the heat radiation to ground over time. Black asphalt highways is a no brainer why the road gets loopy. One way to deal with this is drilling holes into the permafrost and then inserting hollow pipe which allows the cold weather winter air to circulate freezing -40 air and maintain the ice for the 7-8 months of freezing temps. That holds it over for the 4-5 months of higher summer temps.

        But these are the majority of cases we hear about, with the resulting pictures of collapsing buildings and roads. Some sea shore erosion too, but that has always been going on in interglacials. No doubt there is other permafrost melting as well, as described with the rain, but in the scheme of things, things are still melting from end of the last glacial advance.

      • ok thank you MarkW and frankclimate – however – carbon in the form of ??????

        so this is what is nonsensical about it;

        just straight elemental sooty carbon or molecules of CO2 as well and/ or calcium carbonate

        are you saying that whole towns and infrastructure are built on, for example, how many metres of ice on average?? – well know in this region

  8. So the last five years have been wetter than average. Why does that imply that it will be wetter still in the future? Answer, it doesn’t, it is just as likely to return to the average or even go below it.

    • The PDO went positive in 2014. Most likely this is the cause of the recent higher precipitation. When it goes negative again (2022?), then the reverse will happen and that will probably be blamed on climate change as well.

      I wonder what the average of this century would tell us? Maybe no change over long term averages?

      • The link between Alaskan rainfall and the PDO is well known. And the PDO is a part of the ~60 year thermohaline cycle. The climateers love to start their data at the bottom of the cycle and say hey look global warming does X and Y!!! Which is an artefact that disappears when the cycle reverses direction.

        Of course you don’t get much yummy climate money for tracking natural phenomena that humans have no control over.

    • According to the alarmists, any bad trend will continue forever. Any good trend is just weather.

  9. In August, 1967, I was a student-field assistant on a mercury exploration project along the lower kuskokwim River below Red Devil. The project was an experiment with the US Bureau of Mines to see how to deal with permafrost and take samples of the obvious mercury mineralization (the name Red Devil is for the mercury sulfide mineral cinnabar, which is brilliant red). We drilled holes like Catherine in the photo, then we put sticks of dynamite down the hole and blew up the permafrost. Small cracks in the ice radiated out from the blasthole but it was ineffective. WE used a large water canon, a monitor, and the inventor of the Intelligiant, John Miscovich, from Flat, Alaska, personally taught us to use the monitor (cut with speed, transport with volumen). The US Bureau of Mines tried a D-8 bulldozer with rippers. Nothing gazed the permafrost and the exploration project was abandoned. Now, when I read these horror stories about permafrost, I just laugh. The end to this story is well known to a lot of Alaskans and it includes the permafrost winning.

  10. This “perma” frost might have already melted before :

    https://notrickszone.com/2019/08/26/a-1000-year-old-forest-buried-under-alaskas-mendenhall-glacier-uncovers-a-warm-medieval-period/

    An old forest buried some 1000 years ago under an Alaska glacier (Mendenhall Glacier) is poping out, showing that the climate was warmer than today – warm enough to sustain a forest – in this location during the Medieval Optimum.

    And despite this very plausible melting of the permafrost – at least – during the Medieval Optimum, no catastrophic warming occurred.

    And this gem from the EurekAlert! sharticle :
    “As Alaska becomes warmer and wetter, vegetation cover is projected to change and wildfires will disturb larger swathes of the landscape. ”

    So a wetter climate and more vegetation induces more wildfires. Indeed, there are no wildfires in the desert and more vegetation will not disturb anyone or anything expect the brain of some climate clowns.

    • You know, why in deserts are no more wildfires ?
      First there were wildfires, second, there are deserts now. 😀

  11. “Is getting wetter” is almost certainly piffle, what is probably true is that recent years have been wetter than a certain period in the past. “Is getting …” is deeply unscientific and lacking in integrity, hence is ubiquitous in these woke times where feelings and agendas matter more than facts.

  12. There has been a persistent expansive warm blob of water in the Gulf of Alaska for a few years now which definitely influences the jet stream as it comes out of Russia. It primarily has been fed by the El Niño and tropical warmer than average waters moving north on currents.

    The El Niño is now gone and is transitioning into a La Niña taking away the source. As a subsequence, the waters in the GOM will cool as the heat is given up and there is no warm water to replace it. As with everything in the oceans, it takes time but it will ultimately cycle as will the weather patterns it governs. Once the colder water is in place it will persist until somewhere down the road warmer waters will return and the pattern repeats.

  13. Permafrost … “supports Northern infrastructure like roads and buildings; ”

    So, no one knows how to build roads or buildings in regular soil???

      • Just about any south facing hillside will be permafrost free anywhere near the surface here in Fairbanks. Where my house is at on a south facing slope, our well is 368 feet deep. They did not encounter permafrost during the drilling process. Less than 1/2 mile on the north face of the same hill is the permafrost research center and experimental tunnel, it is about 700 feet lower in elevation. Less than 600 feet north of my house is the ridge and permafrost is abundant in the black spruce on the other side of the ridge. Lots of good soils found on the south facing slopes.

        • Thank you Aksurveyor, Great information!

          Does this mean that builders prefer south facing hillside to build on? I guess you avoid a lot of cost and potential problems by building on permafrost free ground.

          If so, can this be seen in the landscape, that south facing hills are more developed than other places?

          /Jan

          • Lol, yes you can see from Google Earth, 64.95n, -147.61w near Fox the clear definition of the ridgeline where the permafrost line is at. There are always the diehard types that want a north facing structure to see the northern lights, they have to build on pilings as another poster mentioned. Building in permafrost always will cost more.
            Current methods for road construction include 6″ or more of foam insulation board with 2 to 4 feet of 8″ rock on top of that, then 2 feet of class A material, 8″ of 1″ minus then 2 to 4 inches of asphalt pavement.
            This may last 2 to 4 years before the frost heaves take over, always hope for longer.

          • Also if you are financing a new home one of the requirements is to have the lot/location of the building footprint drilled to a depth of 30′ to test for permafrost before construction or loan application is approved.

          • ou can see from Google Earth, 64.95n, -147.61w near Fox the clear definition of the ridgeline where the permafrost line is at.

            Very interesting indeed.

            The media usually focus on the negative effects the permafrost melting has for the buildings on top of the existing permafrost. However, A positive side-effect in the long run is that the permafrost free areas increases.

            More good soil to build on.

  14. “in its century-long meteorological record”

    In other words, we know nothing about the past climate of Alaska.

  15. “Over the course of five years, the research team took 2750 measurements of how far below the land’s surface permafrost had thawed by the end of summer across a wide range of environments near Fairbanks, Alaska.”

    So they are only talking about Fairbanks, not the entire state.

  16. As Siberia remains in the headlines, Alaska is experiencing a catastrophe? I’m still waiting for the day when climate change arrives at a place where average people can verify and confirm it.

  17. Finally, something I know about: Alaska…North to the Future, the Last Frontier, etc. Used to live there; grew up there; from 1957, before it was a state; been all over; have many relatives up there even now, some are Natives. I was up there only last fall. I was shocked to see the climate in Alaska is now way too medium!

    Interestingly, several years ago I heard a climate scare story on NPR about a fella who was farming somewhere in western Alaska. They gave the impression the permafrost was melting which made it possible for him to do that. I was skeptical. Did a search and found “Permafrost Farming: It’s Possible!” on modernfarmer.com. It was in Bethel and the truth is the permafrost is not melting unless you scrap it bare like Tim Meyers does and leave it set for two years. Meyer’s Farm has a website as well. Worth looking at, huge veggies. On the down side he is killing the Earth. /sarc.

  18. There is nothing to worry about here. The Eemian was significantly warmer than today with higher sea levels and more ice cap melting yet there was no climate tipping point. The last ice age followed.

  19. “wildfires will disturb larger swathes of the landscape” & hipwaders.
    huh. go figure.

  20. “While the physical basis of Arctic amplification is well understood” Understood, and then lied about.

    Loss of arctic sea ice is a negative feedback, not positive. Ice insulates the ocean, prevents heat loss.

    This is well known, yet is lied about constantly with the suggestion that the ‘dark ocean’ absorbs sunlight and thus warms in the absence of ice.

Comments are closed.