It started with a puddle.
It wasn’t much of a puddle at first. There was just a slump in the ground because of a warm season in a country of perpetual frost.
While scientists have been worried for a while about the defrosting of the permafrost on the edges of the Arctic, there were large areas where nobody particularly worried. Seasons in much of the far north and the subarctic interior are usually so comfortably below freezing, they reasoned, that the permafrost in those areas didn’t face any immediate threats despite the fact that global warming shows up much stronger at the poles.
But no, while climate is measured in data points above and below long term averages, when manifested as weather it doesn’t work quite so smoothly. While the average rise in temperature is not enough yet to melt the permafrost, the number of extremely warm seasons has gone up, seasons, which, when they arrive, defrost the ground in spots, turn it to mud. Where frost holds the soil firm, defrosting causes it to collapse into potholes into which the water gathers.
And potholes form from other causes as well.
A warmer atmosphere absorbs more water and warmer seasons evaporate more water. Places in the quickly-warming Arctic are consequently drier in the summer than they used to be, and fires come to places that used to be too wet to burn. Where wildfires burn carbon is pumped into the atmosphere in huge amounts and the permafrost beneath is warmed. The soil slumps beneath the burns as well, and these indentations also gather water.
The dark water of such puddles absorb the sunlight throughout the long summer days, gathering up more heat in 20 hours of Arctic daylight than a similar puddle could in the tropics with their shorter days. The soil around and beneath the puddles thus gain ever more heat, causing more collapse. Over a few seasons, puddles become ponds, and like self-enlarging solar panels, the ponds continue to melt the permafrost all around.
Beneath nearby trees, as a result of this process, firm soil turns soft. It’s this which has caused the trees to tilt. It’s water, ironically, which provokes their silent drunken dance. Unfrozen water.
But let’s look again at that pond. In winter, when it’s frozen over, you see little places where it’s bubbling up, sometimes several quarts of gas released at a bubble point every day. Methane. And there is indeed toil and trouble in that bubble, bubble. In the short term, methane is a much more potent greenhouse gas than CO². The release of large amounts of methane from the Arctic would give climate change a supercharge, driving up temperatures even faster than they are now. The hockey stick would look more like a ninety-degree turn.
So where is the methane in our pond coming from? It’s a process that’s happening year round, and actually faster in the summer, but the winter frost-over makes it visible. Permafrost is filled with ancient vegetation which begins to rot as soon as the permafrost melts. The methane bubbling up from the bottom of the pond is being produced by vegetation which had been trapped frozen in the ground for sometimes 10s of thousands of years. When decomposition occurs in well-aerated conditions, the bacteria which thrive in those conditions produce CO². When vegetation decomposes in areas low on oxygen, such as at the bottom of a pond, the type of bacteria typical to those conditions produce methane rather than CO².
That bubble, bubble of methane in the ponds actually slows the water from freezing. Thus these natural solar panels, ponds and puddles of unfrozen water, are deployed earlier in spring, later in the fall, extending their warming effect. And more ground is defrosted. More carbon is released. And the faster overall climate change proceeds.
By the end of the century, unless humanity puts the brakes on climate change soon, as much as 35% of greenhouse gas warming may be produced by methane from defrosting permafrost.
Once nature gets directly involved in climate change through feedbacks like this one, you see—and this is only one such complex of feedbacks—once climate change gains momentum through its own processes, there will be no turning it back or putting it under control. Nothing we ourselves could do would offset what nature is capable of once set in motion.
Nature won’t bargain with us. Nature won’t say to us, I agree to lower my methane output if you lower your use of coal-fired electrical plants.
Humanity will simply have to give way against the natural forces we have put in motion.
These are the cold equations of global warming.
If we, if we as human civilization, allow processes like defrosting permafrost to gain traction, then fundamentally we will lose the battle because we will lose our ability to fight back. Trapped in the permafrost where we want it to remain is more than twice as much carbon as there is now in the atmosphere. If we allow it to be released, humanity’s fight against climate change will be subsumed by a more urgent battle: our fight for survival.
The climate in which human civilization grew up will go away. The climate for which life on Earth is adapted will go away. Ever increasing carbon in the atmosphere will dissolve in the ocean and turn it ever more acidic, and much of the life in the ocean will go away. A world of 9 billion people will shrink to feed 5 billion or four. In the nightmare world we have created, our civilization will fight to survive.
We don’t want that.
The answer is prevention, and the only way to prevent the nightmare is by starting now. Every year there are more puddles turning to ponds in the tundra. Every year there are more fires and more drunken forests in the taiga. Every year the price of fighting back goes up, with interest rates compounding like a forest fire.
There is nothing more dangerous than doing nothing, than business-as-usual.
It’s not only Arctic trees which are in danger of having the world made unstable under them. It’s civilization itself.
That’s the message of the drunken trees.
A related blog post here: Albedo and Permafrost – Climate Tipping Points in the Arctic
And here: Simple Sam & the Sinkholes of the Arctic