Methane exceeds nitrous oxide in rivers' contribution to warming


  • Colin Schultz


Nitrous oxide emissions have been the leading area of concern for scientists investigating the role of streams and rivers in global climate change for the past decade. Nitrous oxide, a potent greenhouse gas, is produced in riverbed sediments through nitrification and denitrification. Efforts to understand the rate at which nitrous oxide diffuses through the water to the atmosphere have dominated the field, yet diffusion is not the only relevant mechanism, nor is nitrous oxide the only relevant gas. Observations by Baulch et al. suggest that the global warming potential of methane gas, which they measured bubbling up from several riverbeds, exceeded that of nitrous oxide.