Global warming will free billions of tonnes of carbon from peat bogsNovember 7th, 2008 - 4:34 pm ICT by IANS
Washington, Nov 7 (IANS) Global warming could free billions of tonnes of carbon concentrated in the world’s peat bogs within the coming decades, according to a new analysis of the interplay between peat bogs, water tables and climate change.Such a release of even a tiny percentage would vastly aggravate manmade emissions of carbon, scientists at Harvard University, Worcester State College and Japan Agency for Marine-Earth Science and Technology have warned in a new study.
“Our modelling suggests that higher temperatures could cause water tables to drop substantially, causing more peat to dry and decompose,” said Paul R. Moorcroft, professor of organismic and evolutionary biology in Harvard’s Faculty of Arts and Sciences.
“Over several centuries, some 40 percent of carbon could be lost from shallow peat bogs, while the losses could total as much as 86 percent in deep bogs.”
Found at northerly latitudes, peat bogs are swampy areas whose cold, wet environment preserves organic matter from decaying. This new work shows how warming could upset peat bogs’ stability, which has disproportionately affected the higher latitudes where they are found, said a Harvard statement.
Each square metre of a peat bog contains anywhere from a few to many hundreds of kilos of organic matter, comprising 200 to 450 billion metric tonnes of carbon in peat bogs. This figure is equivalent to up to 65 years’ worth of the world’s current carbon emissions from fossil fuel burning.
“Peat bogs contain vast stores of carbon,” Moorcroft said. “They will likely respond to the expected warming in this century by losing large amounts of carbon during dry periods.”
These findings were published in the current issue of Nature Geoscience.