I’m worried about the sinkholes, Sam.
“You liberals are hilarious,” Simple Sam says, “you’ll worry about anything.”
Correct, Sam. Along with our valentine elbow patches, every liberal is issued with a special worry kit. Every worry kit arrives equipped with worry beads, an instruction booklet containing a standard list of liberal worries (just as you guessed), and with a special section left blank for notes if new worries come into fash…
“But today you are worried about…sinkholes?” says Sam, interrupting.
Alaska sinkholes. Yukon sinkholes. Sinkholes in Nunavut…
“Are you afraid the polar bears are going to trip over them?”
The sinkholes in the far north are the result of melting permafrost, Sam.
“You talked about permafrost before.”
Yes, in Albedo and Permafrost: Climate Tipping Points in the Arctic. The sinkholes are evidence that the permafrost is in fact defrosting. That’s what defrosting permafrost looks like. Holes in the ground. Tipped over houses.
“Big deal. Holes in the ground.”
When permafrost defrosts, Sam, then all the vegetation embedded in those soils defrosts along with it. Carbon which has been fixed and dormant since maybe before the last ice age comes back into circulation. Microbes attack the ancient vegetation, it rots and quantities of it are converted into methane, an extremely potent greenhouse gas with the potential to accelerate the pace of climate change. Bad news.
“Doesn’t warmer weather mean it’s easier for plants to grow in the far north as well? That doesn’t sound so bad.”
You’re right, Sam. Plants are already migrating north. Ecosystems are springing up which were impossible in our previous climate. (Our previous climate from, oh, ten or twenty years ago.) And these changes are going to fix a certain amount of the carbon being released into a more intensely green Arctic landscape. However, this may only slow the problem.
“The greening of the Arctic will not compensate for the huge amount of permafrost carbon that will be released,” says Ted Schuur, an ecosystem ecologist at the University of Florida in Gainesville, who has published a recent study on the matter.
At best, according to the study, the greening will slow the results of released methane, giving humanity breathing room to do something about our own emissions of greenhouse gases before catastrophic warming becomes unstoppable.
“In the initial decade of thaw permafrost will be acting as a carbon sink, and by 30 years it will be a carbon source,” says Schuur.
If we don’t do something big in the next thirty years to fight climate change, those sinkholes could be us, Sam.