Can Wooly Mammoths Save the World?
In a remote corner of Siberia a scientist is creating “Pleistocine Park”.
A version of this story was previously published a couple of years ago as a guest blog post at the Virgin Earth Challenge — an initiative of Sir Richard Branson to stimulate work on cost effective methods to pull carbon out of the atmosphere. It is in part 1 and part 2.
I am currently at Pliestocine Park in Siberia, working on my documentary. If anybody has any questions about the project or questions for Sergey or Nikita Zimov ask them in the comments and I will try to get you an answer.
Two men with a mammoth plan to restore permafrost ecosystems.
The short answer is wooly mammoths could help, but they may not be necessary. More important is the “Mammoth Steppe” ecosystem they once inhabited, a vast grassland extending from Europe across Siberia and into Canada. According to two scientists from a remote corner of Siberia, the Mammoth Steppe played a key role in the planet’s carbon budget and was a powerful driver of global climate during the Pleistocene, the geological era that ended about 10,000 years ago with the end of the last ice age. Taking it a step further, they propose that restoring this ecosystem to its former glory could play an important role in reducing the impact of human-induced climate change today.
This bears a moment’s thought. While it may sound crazy, this could be a classic case of truth being stranger than fiction. For the past four weeks I have been living with Sergey and Nikita Zimov, a father and son team of scientists, at their home and research station in Chersky, Siberia. I’ve been shooting footage for a documentary I’m making about Pleistocene Park, their unusual large-scale experiment — and plan to save the world.
A cloned wooly mammoth may well walk the earth in the not so distant future. Harvard geneticist George Church, in collaboration with San Francisco based nonprofit Revive and Restore, has successfully inserted wooly mammoth DNA into an Asian elephant genome — an important step towards mammoth cloning. The Zimovs, however, are adamant that they don’t need an actual mammoth, or any other extinct creature to proceed. They have a more ambitious plan: to resurrect, not a single species, but an entire extinct ecosystem. In fact, they have already started. An hour’s boat ride south of their research station, they have fenced off several square kilometers of land and began populating it with herbivores: Yakutian horses, reindeer, elk, moose, European bison, and muskoxen. They are working on bringing more: Canadian bison, yaks, wolves, and Sergey really wants a tiger. They aren’t opposed to mammoth cloning mind you. And they would be happy to host a baby wooly mammoth at Pleistocene Park. They just have more pressing concerns at the moment.
But what does an extinct ecosystem have to do with climate change and how does Sergey’s menagerie fit into this? Throughout the Pleistocene, an era from 2.5 million to 12,000 years ago, the Mammoth Steppe was an incredibly productive grassland populated by very large numbers of big herbivores — think African Serengeti but with more animals and, well… woolier. The Zimovs actually calculated herbivore density based on bones they found in an eroding riverbank near their house. I won’t subject you to the math; you can read about it in their peer reviewed paper; though the gist is that, if Sergey’s house had existed during the Pleistocene, he could have looked out his window onto the Kolima river floodplain and seen as many as 1000–3000 large herbivores grazing below, including approximately 70 wooly mammoths. All these animals ate grass, a lot of grass, and pooped, a lot of poop. In the Arctic the only place anything decomposes is in the belly of a large hairy beast. Sergey uses an economic analogy: It’s not how much money you have in the bank, it’s how fast this money turns over. A horse, or a mammoth, can turn grass into fertilizer in about 20 hours.
All this fertilizer had a profound impact on the global carbon budget. During the Pleistocene grass grew like crazy with a constant supply of manure and 24 hour daylight of arctic summer. Dung mixed with wind blown dust, and built carbon-rich soil, layer by layer. Underground, the permafrost crept upwards, freezing grass roots, animal bones, and in some cases entire animals, meat, hair and all. Over time this process effectively pulled carbon out of the atmosphere and locked it in frozen “Yedoma” soils. It’s under my feet as I type this, tens of meters deep. Think of it as a frozen compost pile, stretching to the horizon, actually stretching across several time zones. And now, due to global warming, it’s starting to melt. Perhaps you see where this is going…
Sergey Zimov emerged from Siberian obscurity in the late 90’s and early 2000’s when he published a series of papers in the scientific journals Science and Nature quantifying just how much carbon is stored in these Siberian Yedoma soils: it is around 500 gigatons, almost equal to the amount humans have put into the atmosphere since the beginning of the industrial revolution. More recent calculations by an international group of scientists, including Sergey, which looked at all permafrost soils, not just Yedoma, have put the number at 1672GtC. That’s more carbon than all above ground vegetation and the earth’s atmosphere combined!
Nobody is quite sure when it will melt, how fast it will melt, how much of it will melt, and what will happen to all that carbon. The arctic is warming much more rapidly than the rest of the planet. Researchers from around the world are trying to answer these questions, including through ongoing research projects at the Zimovs’ Siberian field station. But the Zimovs have made some rough calculations. Nikita told me he expects that within twenty years his region of northern Siberia risks, on an annual basis, emitting as much carbon as all the cars and trucks and factories and power plants of the United States. Much of it will be emitted in the form of methane which in the short term is 23 times more potent a greenhouse gas than CO2. Getting a handle on these emissions is critical because currently this permafrost carbon feedback loop isn’t included into global climate models and therefore isn’t taken into account in climate accords like the recent Paris Agreement. This means that we will likely have to make deeper cuts in emissions than currently envisioned and/or warming will be worse than current estimates.
During the Pleistocene, the Mammoth Steppe ecosystem drove global climate in two directions, both positive feedback loops magnifying swings in temperature, and both powerful ones according to the Zimovs. During cool periods, it sucked carbon out of the atmosphere and froze it underground, maintaining cool conditions. During warming events, like the transition from Pleistocene to Holocene 10,000 years ago, melting permafrost rapidly dumped large amounts of carbon and methane back into the atmosphere, accelerating and amplifying the warming. The physical effects on the landscape are visible today. A once flat plain collapsed as ice wedges within the soil melted, creating gullies and ravines and leaving thermokarst lakes dotting the landscape.
The Zimovs propose a few mechanisms by which restoring the Mammoth Steppe would help mitigate global warming:
First, it will once again start drawing carbon from the atmosphere and storing it in the soil. Although the amounts of carbon are significant, don’t expect any quick and easy fixes on this front. Nikita created a model of carbon sequestration, past and future, in northern soils. Even in a best-case scenario, if we stopped burning fossil fuels now, it would take thousands of years to remove the carbon we have already pumped into the atmosphere.
Second, grasslands have a very high albedo. This means they reflect much more solar radiation back into space then the tundra, blueberry bushes, and larch trees that currently dominate much of the north. More research is needed about just how large this effect may be but Nikita and others suspect it could be very significant.
Third, and far and away the largest effect in the short term: restoring the Mammoth Steppe will keep permafrost frozen, thus keeping all that carbon, gathered over hundreds of thousands of years, locked in the ground. How will it do this? In the winter, when air temperatures can reach -50c, a thick layer of snow insulates the earth from the polar cold — effectively keeping the soil warmer than it would otherwise be. Vast herds of animals would spend the winter with one thing on their mind: food. They would trample the snow as they walked and they would paw through it searching for every last blade of frozen grass, thus greatly reducing its capacity to insulate. This is a little counterintuitive but think of it this way: Siberian snow is like a light fluffy meter thick down comforter shielding the cold-ish (-3c) ground from the much colder (-40c) air.
How big of an effect do animals removing this insulating snow have? Last year, at Sergey’s suggestion, a group of American scientists installed a temperature sensor in the middle of the most heavily grazed meadow in Pleistocene Park and another, in a similar area, but outside the fence, where the snow is undisturbed by animals. Outside the fence the March soil temperature at a depth of .5 meters was -10c. In the trampled area it was -24c. These are preliminary results and more measurements need to be made, but even Nikita was surprised by the strong effect winter grazing had on soil temperatures. This summer they drilled a borehole in the park to measure year-round temperature trends at greater depths. We should know more as data from this sensor becomes available.
Sergey Zimov does not suffer from low self confidence: “I don’t often make mistake, usually my prediction accurate.” However not everything has worked out as planned. In 1988, Sergey took delivery of the first animals for his park, a herd of semi wild horses. He calculated that there would be no need for fences. Why would the horses go anywhere? They weren’t privy to Sergey’s logic and promptly made the 500km trek back to their home pasture in the dead of winter. 3 years ago Nikita drove a Russian military truck with giant off road tires across thousands of kilometers of roadless wilderness, following frozen rivers and tracks in the snow for weeks to bring a load of elk to the park. The Zimovs failed to accurately calculate how high an elk can jump. The last one was seen about a year ago several kilometers outside the park and heading south. During my visit to the park I got conscripted into a couple days labor improving their fencing.
Most of the Zimov’s science is groundbreaking and as such controversial. They have managed to ruffle a lot of feathers over the years and definitely have their detractors. That said, the volume of papers they publish in top tier scientific journals would make most scientists envious. On the subject of mitigating climate change, whether they are right about every detail or not, the stakes are too high to ignore them.
Sergey seems rather miffed that the world hasn’t wholeheartedly embraced his idea and run with it already. Nikita is bit more pragmatic. Like his father, he is confident in the plan but he acknowledges there are some kinks to be worked out. Things like the height of fences, or the difficult logistics of shipping a herd of bison from Canada to Siberia. More importantly things like finding the right mix of animals to sustain a grassland ecosystem in the far north. Nikita’s background is in advanced mathematics and he acknowledges that something as complex as an ecological system won’t be figured out by calculation alone. There is still a lot of trial and error ahead. He also sees need to engage with a legitimately skeptical world. After all, they are talking about radically reshaping the ecology of the largest landmass on earth. What could possibly go wrong?
Sergey and Nikita are insistent that they do not need an actual live mammoth to carry out their plans, so this will irritate them to no end — but I personally find a certain poetic beauty in the idea that wooly mammoths, driven to extinction by short sighted human hunters 10,000 years ago, could yet save us from our own modern day poor judgment. Of course, another caveat: nothing is going to save us if we don’t take steps to save ourselves and stop pumping CO2 into the atmosphere. But in the short term mammoths, and/or their ecosystem, can keep permafrost frozen and prevent a worst case scenario that is far worse that the current worst case scenarios. In the longer term they can start the slow process of reversing the damage we have done. And as Sergey likes to point out, it’s extremely cheap. This has got to be among the fattest, lowest hanging fruit there is to mitigate climate change. The Zimovs, who have little time or tolerance for bureaucracy of any sort, have embarked on this project with no financial support from governments, non profit foundations, or corporations. To date the entire thing has been funded by their personal income running the research station, feeding and housing foreign researchers, and maintaining their experiments when the foreigners depart to spend their winter somewhere more civilized.
This DIY approach to global salvation may have limits. I find it hard to imagine they can take it to the next level without support from outside entities. On the other hand they have surprised everybody by taking it this far. One question remains: will the mammoths cooperate? Because as we all know, an elephant never forgets, and after 10,000 years on ice they may still have beef with our species. Who wouldn’t?
Some Links:
-Here is a short article Sergey wrote in Science magazine detailing his plan:
http://www.pleistocenepark.ru/files/Zimov_PleistocenePark_Science.pdf
-Here is an excellent article by Adam Wolf that goes into more details. It also has some wonderful illustrations:
http://www.pleistocenepark.ru/files/Wolf_PleistocenePark_StanMag.pdf
-Here is a link to the official website for Pleistocene Park. Lots of good photos:
http://www.pleistocenepark.ru/en/
-And here is a link to the Facebook page for the documentary I am making about the project:
https://www.facebook.com/PleistoceneParkMovie?ref=hl
Please “like” it if you are interested in learning more about the progress of Sergey and Nikita’s project.
