Joel Hollingsworth wrote:
I had mostly heard of nitrogen oxides being made in internal combustion engines, only they tend to transform into ozone (aka smog) if they aren't caught up in acid rain or broken down by catalytic converters. I think the major acid rain concern from coal was sulfur oxides, but I think first world furnaces tend to scrub those now, too.
eeek... you'll teach me to be flip...

ops:
I think your right about the importance of sulfur contribution to acidification. And I found one piece of evidence that current levels in NE US are less then if no EPA regulation had occurred.
I was focused on the acid rain input as well as dry deposition of industrial NO emissions rather than the ozone pathway. It seems that there is not a clean cut between cars and other industrial sources, though point sources are easier to regulate.
"According to the U.S. Environmental Protection Agency (EPA),1 the major sources of NOx in the eastern United States during 2004 were on-road vehicles (36%), followed by the power industry (23%), off-road mobile sources (19%), and the remainder attributed to area sources."
http://www.epa.gov/AMD/peer/products/188329_Gego_AIR.pdf But if you look at N cycling from the perspective of aquatic ecosystem then you have a different set of impacts. It looks like this Chesapeake study also describes fossil fuel burning in general but also identifies volatilization of ammonia from feed lots, and refutes earlier models in that:
"Substantial quantities of nitrogen can be deposited from the atmosphere as
‘‘dry deposition,’’ which includes aerosols and other particles and uptake of
gaseous forms of nitrogen by vegetation, soils, and surface waters. Both in the
United States and Europe, the extremely sparse spatial coverage in networks for
measuring dry deposition severely limits estimation of this process (Holland
et al., 2005)."
http://www.whoi.edu/science/seagrant/Publications/ocean/Howarth.2008.Narragansett.Bay.book.pdf And it sounds like it ain't over..
"In 2020, with a projected population of 8.5 billion and an assumed 100% increase in per capita energy consumption relative to 1980 by the lesser developed countries,
we predict an approximate 25% increase in total nitrogen deposition in the more-developed-country source regions such as North America. In addition, reactive nitrogen deposition will at least double in less-developed regions, such as SE Asia and Latin America, and will increase by more than 50% over the oceans of the Northern Hemisphere. Although we also predict significant increases in the deposition of nitrogen from fossil-fuel sources over most of the Southern Hemisphere, particularly Africa, the tropical eastern Pacific, and the southern Atlantic and Indian Oceans, biomass burning and the natural sources of nitrogen oxides (
lightning and biogenic soil emissions) are also important in these regions. This increased deposition has the potential to fertilize both terrestrial and marine ecosystems"
http://md1.csa.com/partners/viewrecord.php?requester=gs&collection=ENV&recid=3631720&q=biomass+burning+and+nitrogen+oxide&uid=788964746&setcookie=yes Based on my very limited knowledge (keep learnin' me) I propose that nitrogen deposition from a variety of industrial sources is not a thing of the past.
If you google scholar 'lightning induced nitrogen oxide' there are some juicy articles...