6.6 Atmospheric reactions of nitrogen species

Nitrogen compounds, especially NOx when sunlight is available play an important role in tropospheric photochemistry catalizing O3 production in the troposphere. Tropospheric ozone production is limited by NOx abundance, but heavily polluted areas experience higher ozone concentrations. Nitrogen oxides also will interact with volatile organic compounds to form ozone. In Chapter 8 ozone chemistry is described in more details.

Nitrous oxide (N2O) is a key nitrogen compound in environmental sciences due to its properties as greenhouse gas, and also because of its role in stratospheric ozone destruction. Because it has a relatively long residence time without major tropospheric sink, it can get to the stratosphere where it responds to UV light by photodissociation to N2 and O or – less likely – combines with O producing 2NO. This latter gas is has a key role in photocatalitic destruction of stratospheric ozone. In this sense, N2O can be considered as a long lifetime carrier of NO. The environmental significance of N2O is also indicated by the fact that emission of this gas is regulated by the Kyoto protocol.

Atmospheric concentration of nitrogen compounds is monitored regularly in Hungary and also a national emission inventory has been presented for the period 1986−2006.

References

Melillo J.M., Field C.B., and Moldan B.. 2003. Interactions of the Major Biogeochemical Cycles: Global Change and Human Impact. Island Press. ISBN 978-1559630665.

IPCC, 2007: Fourth Assement Report: Climate Change 2007: The Physical Science Basis Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. 2007. Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K.B., Tignor M., and Miller H.L.. (eds.). Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Haszpra L.. 2003. Atmospheric Greenhouse Gases: The Hungarian Perspective, Springer. ISBN 978-90-481-9949-5 (Print). ISBN 978-90-481-9950-1 (Online).

Horváth L., Grosz B., Machon A., Balogh J., Pintér K., and Czóbel S.. 2008. Influence of soil type on N2O and CH4 soil fluxes and in Hungarian grasslands. Commun Ecol. 9 (Suppl). 75-80. doi: 10.1556/Com.Ec.9.2008.S11.

Wagner S.C.. 2012. Biological Nitrogen Fixation In: Nature Education Knowledge. 3. (10). 15.