Climate change is changing the environment. Studies have shown that higher levels of greenhouse gases like carbon dioxide (CO2) are warming the planet. But it isn't easy to predict how those changes will affect life in the future. To fix that, some researchers are bringing the future to life, today, no time machines involved.
In Minnesota, scientists with the Department of Energy are pumping carbon dioxide into the air to see how wetlands respond in a project called Spruce and Peatland Responses Under Climatic and Environmental Change, or SPRUCE. The SPRUCE project set up huge enclosures, open to the air on top to see how the semi-enclosed environment would react to elevated CO2 levels and temperatures. (CO2 is heavier than air, so we're pretty sure most of it should stay in the enclosures.) The project was formally started this week.
The ten enclosures are roughly 40 feet across and 25 feet tall. Inside a few of them, researchers are keeping CO2 levels at 900 parts per million. In today's atmosphere, CO2 levels in the air are around 400 parts per million. The experimental enclosures are also equipped with heaters that can keep the temperature inside 9 degrees warmer than the temperature outside.
“We think this gives us a good glimpse as to what future climates might look like,” Paul Hanson the experiment's project coordinator, told Nature. “It allows us to cheat today's conditions and take on the whole ecosystem, from the top of the trees to the deep peat.”
The deep peat is important, because peat, a dense, water-logged mixture of plant remains, contains large amounts of carbon that have built up over thousands of years. One third of the world's terrestrial (non-atmospheric) carbon is stored in peat bogs. Scientists think that once the peat in these wetlands warms up, it could start to release that carbon in the form of some kind of greenhouse gas. But they aren't sure if it will be CO2 or the even more potent methane, which has the potential to cause even greater levels of global warming.
Over the next 10 years, the scientists plan to keep the experiment running year-round, checking to see what happens to the ecosystem inside the cages.