ISSN:
1573-515X
Keywords:
ammonia emissions
;
global nitrogen cycle
;
nitric oxide
;
nitrogen deposition
;
nitrogen pollution
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
Notes:
Abstract Increases and expansion of anthropogenic emissions of both oxidized nitrogen compounds, NOx, and a reduced nitrogen compound, NH3, have driven an increase in nitrogen deposition. We estimate global NOx and NH3 emissions and use a model of the global troposphere, MOGUNTIA, to examine the pre-industrial and contemporary quantities and spatial patterns of wet and dry NOy and NHx deposition. Pre-industrial wet plus dry NOx and NHx deposition was greatest for tropical ecosystems, related to soil emissions, biomass burning and lightning emissions. Contemporary NOy+NHx wet and dry deposition onto Northern Hemisphere (NH) temperate ecosystems averages more than four times that of preindustrial N deposition and far exceeds contemporary tropical N deposition. All temperate and tropical biomes receive more N via deposition today than pre-industrially. Comparison of contemporary wet deposition model estimates to measurements of wet deposition reveal that modeled and measured wet deposition for both NO 3 − and NH 4 + were quite similar over the U.S. Over Western Europe, the model tended to underestimate wet deposition of NO 3 − and NH 4 + but bulk deposition measurements were comparable to modeled total deposition. For the U.S. and Western Europe, we also estimated N emission and deposition budgets. In the U.S., estimated emissions exceed interpolated total deposition by 3-6 Tg N, suggesting that substantial N is transported offshore and/or the remote and rural location of the sites may fail to capture the deposition of urban emissions. In Europe, by contrast, interpolated total N deposition balances estimated emissions within the uncertainty of each.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01007572
