Although vegetation growth in the Arctic is boosted by global warming, it’s not enough to offset the carbon released by the thawing of the permafrost beneath the surface, University of Florida researchers have found in the first experiment in the Arctic environment to simulate thawing of permafrost in a warming world.
Twice as much carbon is frozen in Arctic permafrost as exists in the atmosphere today, and what happens to it as it thaws – releasing greenhouse gases that fuel climate change – is a key question, said professor Ted Schuur…
“The plants like it when they’re warmer, so their growth is increasing, and if you just watch the tundra in the summertime and you look at the balance between what the plants are doing and what the soil is doing, the plants actually offset everything that happens in the soil. They’re growing faster, getting bigger and taking carbon out of the air,” Schuur said. “From the perspective of climate change, that’s a good thing, tundra vegetation is making up for any carbon you’re losing from the soil.”
The hitch? The Arctic’s short summers do not make up for the long winters.
Researchers are interested in the permafrost of the polar regions because these soils – permanently frozen at great depths and for tens of thousands of years – are vulnerable to global warming…
As the experiment continues into the next three-year cycle, Schuur said he is looking for a point at which the plants hit a growth limit and stop absorbing more carbon, while the thawing permafrost continues to release carbon…
One of the successes of the experiment, Schuur said, was finding a way to model carbon release from permafrost in the environment on a year-round basis. Previous studies had used miniature greenhouses in summer months, but creating a warming situation in the winter was more challenging.
“We wanted to warm the tundra and cause the permafrost to recede. This is the first experiment to isolate that effect in the field, so the first thing we show is that we’re able to simulate what will happen in a future world when the permafrost degrades,” Schuur said…
The studies confirm that a significant amount of carbon is released from thawing permafrost and highlight that there are factors beyond simply temperature that affect carbon release, Schuur said.
New variables identified by Professor Schuur and postdoc researcher Susan Natali range from water content to the ratio of nitrogen to carbon in the permafrost soil.
There’s the added existential fillip that these researchers are staff at a university in Florida – therefore they’re overseen by politicians and ideologues who refuse to accept any scientific acknowledgement of climate change.
In fact, there is at least one city in another neo-Confederate state where local politicians made it illegal for public funds to be used to publish any document describing sea levels as rising – even though that happens to be a problem in that city. 🙂
