Glob. Biogeochem. Cycles http://doi.org/hx4 (2012)

Credit: © ISTOCKPHOTO/THINKSTOCK

Permafrost holds a large reserve of organic carbon — estimated to be ∼50% of the global belowground stock. Melting permafrost may result in a large release of this carbon as carbon dioxide or methane, which would be a positive climate change feedback. Substantial carbon emissions have been observed from lakes in permafrost areas, but the emissions from small ponds are not taken into global emission estimates as they are invisible to most satellites.

Anna Abnizova, of the Alfred Wegener Institute, Potsdam, Germany, and colleagues, studied water bodies on Samoylov Island, northeastern Siberia — a continuous permafrost zone. They quantified the carbon flows and carbon dioxide emissions from lakes, ponds and outlets.

Carbon dioxide emissions from lakes and ponds, which cover 25 per cent of the island, accounted for 74–81per cent of net emissions — 28–43 per cent of the total was from ponds and 27–46 per cent from lakes. Excluding ponds from total summer carbon dioxide emissions results in an underestimation of 35–62 per cent. Ponds in permafrost regions are too small to be represented in current model simulations, but the authors conclude that they should be included in future estimates.