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Gary Price
Wolf, A. (2008, September/October 2008). The big thaw. STANFORD Magazine, 37, 62-69.
As Siberia's permafrost melts, billions of tons of carbon could escape and heat the planet. Do animals and plants hold a key to Earth's thermostat?
"Sergei looks at the bones buried everywhere under this landscape and proposes that those mammoths would have crushed nearly every tree in Beringia, leaving an extensive grassland. Much as we watch with alarm as Arctic sea ice melts and reveals a dark ocean to absorb the sun's rays, the loss of mammoths and consequent northward expansion of forests would have an unambiguous warming effect. In springtime, while grasses lie dormant under a thin blanket of snow, black trunks of trees tower above the surface and absorb the sun's light as it emerges from polar winter. The difference between energy absorbed by trees or energy reflected by snow in those first weeks of spring is what determines the accretion or thaw of permafrost. This is a major reason why land in high latitudes is warming faster than any other place on Earth.
Just as many authors argue that the northward advance of forests is accelerating warming today, Sergei reasonably suggests the corollary: mammoths and other herbivores kept the climate of their day cool.
The mass extinction of the fauna of the Mammoth Steppe—mammoths, bison, horses, rhinos, cave lions, beavers, reindeer, elk, deer and many others—is still a source of active debate between two camps: those who argue that the animals died out and others who argue that human settlers in Beringia slaughtered the animals en masse on their way to North America. Sergei is unreservedly in the latter group: “In America, 500 men with guns killed 50 million buffalo in five years. In Australia, the 23 largest herbivores were extinct in the first century after humans arrived. What makes you think Siberia is any different?” He perceives great resistance to this idea and has amassed a large arsenal of evidence. He will point out that pollen records show a very productive landscape before, during and after the megafaunal extinction. He will name every climatic zone on Earth where mammoth remains have been found—clearly an adaptable creature.
For Sergei, this means that in principle, there is no reason why mammoths could not exist here now. As he mulls over the warming following the end of the Pleistocene, the contemporary taiga overlaying the frozen roots of a grassland fauna just two feet below, the history of humans and extinction, he wonders: What if driving the mammoth extinct at the end of the Stone Age brought us this warm climate we have today? If we recreated the Mammoth Steppe, could we engineer global cooling?
Thus was born Pleistocene Park, a grand scientific experiment to recreate the complex set of interactions between fauna, flora and their physical setting and test whether re-establishing the Mammoth Steppe could alter the direction of the climate system.
…But what about the mammoths? Left to his own devices, Sergei has come up with a pragmatic solution. Approaching the tower he built to monitor the plant physiology of the park, he points to the wrecked underbrush strewn about the path. “Three mammoths came through here, two female mammoths, one child,” he announces. I am bewildered, unable to imagine what it is like to walk around in the present, all the time aware of ghosts of the deep past. He continues: 'But today we have no mammoths, so I use a tank.'
Among the assorted vans, Jeeps, boats, ATV, motorcycle, barge, float plane and hovercraft at the station there is a tank. A real tank, with Caterpillar treads.
Sergei bought it new in Yakutsk a decade ago and drove it to Cherskii himself, several hundred miles in the dead of winter by dirt road (and, as necessary, overland). It is easy to see where this tank has been: in place of the shrubs and larch surrounding us everywhere there is a trail of succulent brome grass, spontaneously emerging and continuing to thrive several years later. Only after seeing the tank does it begin to dawn on me what life here used to be. Mammoths were the tanks of the former world.
…While in some sense Pleistocene Park is an attempt to understand the Mammoth Steppe ecosystem before the age of man, the real mission may as well be to see how restoration of that ecosystem can prevent the runaway warming mankind has never experienced."
https://stanfordmag.org/contents/the-big-thaw
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