Nitrogen global emission

Transportation is also the emissions leader. About 75 percent of carbon dioxide emissions and 45 percent of nitrogen oxide emissions come from the transportation sector. If rising levels of CO, are found to be responsible for global warming, and measures are put in place to severely curtail CO, emissions, the measures will have the greatest impact on the transportation sector. 

Hameed, S and J. Dignon, Global Emissions of Nitrogen and Sulfur Oxides in Fossil Fuel Combustion, J. Air Waste Manage. Assoc., 42, 159-163 (1992). 

On a global basis, however, these estimated pollutant emissions of NO2 are probably a minor factor in the total circulation of nitrate compounds within the atmosphere. It is estimated (3) that natural emissions of NO2 may be as much as 15 times greater than the pollutant emissions or more than 700 X 10 tons. This estimate of natural emissions is based on an estimated nitrogen cycle for the atmosphere, and it is believed to result from NO produced by biological reactions. Peterson and Junge (24) recently estimated natural nitrogen compound emissions may be no more than twice as large as currently estimated pollutant sources. 

The oxides of nitrogen, NO and N02, are among the most important molecules in atmospheric chemistry. We will devote in this book considerable attention to their chemistry. Estimated global emissions of NO are given in Table 2.6. Aircraft emissions are listed separately in Table 2.6 because they are released predominantly in the free... 

Of the various emissions of nitrogen compounds which enter into the atmosphere, the oxides N2O, NO, NO2, and NH3, NH, NOJ are the most important species. Natural sources considerably exceed the sources from anthropogenic activity. Global emissions from natural sources are summarized in Table 5.13 [26] amounts originating during the combustion processes may be found in Table 5.14 [26]. For an estimate of emissions from central European countries, Yugoslavia, Roumania and USSR in 1980 see Table 5.15. 

Table 5.13. Natural global emissions of nitrogen compounds (originating during biological processes) [26]...

Table 6.14. Global emissions of nitrogen compounds, produced during combustion, expressed as NO2 (t 10 yr -]... 

Dignon, J.,"and Hameed, S. (1989) Global emissions of nitrogen and sulfur oxides from 1860 to 1980, J. Air Pollut. Contr. Assoc., 39, 180-186. 

Martin, R. V, D. I Jacob, K. Chance, T. R Kurosu, P. I. Palmer, and M. J. Evans (2003) Global inventory of nitrogen oxide emissions constrained by space-based observations of NO2 columns. Journal of Geophysical Research 108, 4537, doi 10.1029/2003JD003453... 

The atmospheric cycles of sulfur and nitrogen include the following components (a) emission of the compounds from the earth s surface into the atmosphere (b) transport and transformation of these compounds in the atmosphere (c) and wet and dry removal of the compounds from the atmosphere. The relationship between emissions levels and air and precipitation quality is a physical fact if the time and space boundaries are defined appropriately. For example, if the global emissions of sulfur increase, the average air quality for sulfur for the globe will decrease. This section will examine annual average values for source emissions estimates and for precipitation quality, for the northeastern United States for the mid-1950 s versus the late 1970 s. 

Plant nutrient sulfur has been growing in importance worldwide as food production trends increase while overall incidental sulfur inputs diminish. Increasing crop production, reduced sulfur dioxide emissions, and shifts in fertilizer sources have led to a global increase of crop nutritional sulfur deficiencies. Despite the vital role of sulfur in crop nutrition, most of the growth in world fertilizer consumption has been in sulfiir-free nitrogen and phosphoms fertilizers (see Fertilizers). 

Power plant emissions result from the comhustion of fossil fuels such as coal, gas, and oil. These emissions include sulfur dioxide (SO,), nitrogen oxides (NO.,), particulate matter, and hazardous air pollutants, all of which are subject to environmental regulations. Another emission is carbon dioxide (CO,), suspected of being responsible for global warming. 

Natural gas will continue to be substituted for oil and coal as primary energy source in order to reduce emissions of noxious combustion products particulates (soot), unburned hydrocarbons, dioxins, sulfur and nitrogen oxides (sources of acid rain and snow), and toxic carbon monoxide, as well as carbon dioxide, which is believed to be the chief greenhouse gas responsible for global warming. Policy implemented to curtail carbon emissions based on the perceived threat could dramatically accelerate the switch to natural gas. 

Banger K, Tian H, Lu C. Do nitrogen fertilizers stimulate or inhibit methane emissions from rice fields Global Change Biol. 2012 18 3259-3267. 

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