Nitrous oxide (N2O) is a powerful greenhouse gas and the main driver of stratospheric ozone depletion. Since soils are the largest source of N2O, predicting soil response to changes in climate or land use is central to understanding and managing N2O. Here we find that N2O flux can be predicted by models incorporating soil nitrate concentration (NO3−), water content and temperature using a global field survey of N2O emissions and potential driving factors across a wide range of organic soils. N2O emissions increase with NO3− and follow a bell-shaped distribution with water content. Combining the two functions explains 72% of N2O emission from all organic soils. Above 5 mg NO3−-N kg−1, either draining wet soils or irrigating well-drained soils increases N2O emission by orders of magnitude. As soil temperature together with NO3− explains 69% of N2O emission, tropical wetlands should be a priority for N2O management.

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Changes in the percentages of eight main surface wind directions at 14 meteorological stations in Estonia, Northeast Europe, were studied during 1966-2008. Long-term changes in wind directions are related to variations in the large-scale atmospheric circulation but partly also to changes in the surroundings of the stations and in wind obstacles. Significant alterations in wind directions were determined, and found to be the strongest in the winter season. The percentages of W and SW winds have clear positive trends, while SE, E and NE winds are characterized by negative tendencies in winter. In conclusion, wind directions have probably been shifted from east to west. Differences in trends between the stations are explained by changes in wind obstacles around the stations. The trends in wind roses in Estonia were caused by the intensification of the westerly circulation over the Atlantic/European sector during the winter season.