Stop hoping we can fix climate change by pulling carbon out of the air, scientists warn
SCIENTISTS are expressing increasing skepticism that we’re going to be able to get out of the climate change mess by relying on a variety of large- scale land use and technical solutions that have been not only proposed, but often relied upon in scientific calculations.
Two papers published last week debunk the idea of planting large volumes of trees to pull carbon dioxide out of the air - saying there just isn’t enough land available to pull it off - and also various other strategies for “carbon dioxide removal,” some of which also include massive tree plantings combined with burning their biomass and storing it below the ground.
“Biomass plantations are always seen as a green kind of climate engineering because, you know, everybody likes trees,” said Lena Boysen, a climate researcher at the Max Planck Institute for Meteorology in Germany, who led one of the new studies while a researcher at the Potsdam Institute for Climate Impact Research. “But we just want to show that that’s not the complete story. They cannot do that much.”
Forests have long been recognised as one of the world’s most important natural carbon sinks, capable of storing large amounts of carbon that would otherwise end up in the atmosphere. Simply preserving the world’s forest resources - and replanting areas that have already been deforested - is viewed as a an important step in protecting the climate.
But for years, scientists have discussed the idea of going farther by using large plantations full of fastgrowing, carbon- storing trees to pull extra carbon emissions out of the atmosphere, a strategy sometimes called “afforestation.” But the amount of land and other resources this strategy would require to actually help us meet our global climate goals - namely, keeping global temperatures within at least 2 degrees of their preindustrial levels - is completely impractical, according to Boysen’s new study in the journal Earth’s Future, and would require the destruction of huge amounts of natural ecosystems or productive agricultural land. —WP-Bloomberg