New research has discovered what one researcher labelled an “accounting error” in the current calculations of how much carbon is absorbed by continents. According to the new research to be published in the journal Science, the amount of greenhouse gas currently taken in by forests and other carbon sinks is less than has previously been assumed, thanks to the failure to calculate the methane emissions from freshwater areas.
“Methane is a greenhouse gas that is more potent than carbon dioxide in the global change scenario,” said John Downing, an Iowa State University professor in the ecology, evolution and organismal biology department. “The bottom line is that we have uncovered an important accounting error in the global carbon budget. Acre for acre, lakes, ponds, rivers and streams are many times more active in carbon processing than seas or land surfaces, so they need to be included in global carbon budgets.”
The new research studied methane fluxes from 474 freshwater areas and found that the methane release changes the total amount of greenhouse gasses absorbed by natural continental environments – the most obvious being the forest – by at least 25 percent.
This new study will help scientists create a better understanding of the balance between carbon sequestration – the storing of carbon in biomass across our planet – and the greenhouse gasses released from fresh water areas.
Methane emissions occur continuously in small measures from the surface of water bodies all over the planet, says David Bastviken, principal author and professor in the department of water and environmental studies, at Linköping University in Sweden. However, “greater emissions occur suddenly and with irregular timing, when methane bubbles from the sediment reach the atmosphere, and such fluxes have been difficult to measure,” Bastviken added.