New estimates of global emissions of N2O from rivers and estuaries
نویسندگان
چکیده
We present new estimates of emissions of nitrous oxide (N2O) from rivers and estuaries, using the NEWS-DIN model. NEWS-DIN is a model of the global transport of dissolved inorganic nitrogen (DIN) by rivers to coastal waters (Dumont et al. forthcoming). It calculates DIN export rates as a function of watershed characteristics, including human influences. We used the calculated DIN export rates by river to estimate emissions of N2O from aquatic systems. Our new estimates for N2O emissions from rivers and estuaries are 1.26 and 0.25 Tg N/year, respectively, totaling to 1.5 Tg N/y. These estimates are somewhat higher than earlier estimates. Next we investigated the consequences of our new estimates for the global N2O budget. We did this by running an atmospheric box model and comparing the results to observed values from different monitoring networks. The results indicate that the global budget using the new NEWS-DIN estimates for aquatic N2O emissions is in good agreement with observed concentrations.
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