scholarly journals Impact of new laboratory studies of N2O5hydrolysis on global model budgets of tropospheric nitrogen oxides, ozone, and OH

2005 ◽  
Vol 32 (9) ◽  
Author(s):  
M. J. Evans
Keyword(s):  
Nitrogen Oxides ◽  
Global Model ◽  
Laboratory Studies

scholarly journals The global lightning-induced nitrogen oxides source

2007 ◽  
Vol 7 (1) ◽  
pp. 2623-2818 ◽  
Author(s):  
U. Schumann ◽  
H. Huntrieser
Keyword(s):  
Nitrogen Oxides ◽  
Climate Changes ◽  
Trace Gases ◽  
Tropospheric Chemistry ◽  
Laboratory Studies ◽  
Mass Source ◽  
Uncertainty Range ◽  
Airborne Measurements ◽  
Model Studies ◽  
Uncertainty Factor

Abstract. The knowledge of the lightning-induced nitrogen oxides (LNOx) source is important for understanding and predicting the nitrogen oxides and ozone distributions in the troposphere and their trends, the oxidising capacity of the atmosphere, and the lifetime of trace gases destroyed by reactions with OH. This knowledge is further required for the assessment of other important NOx sources, in particular from aviation, the stratosphere, and from surface sources, and for understanding the possible feedback between climate changes and lightning. This paper reviews more then 3 decades of research. The review includes laboratory studies as well as surface, airborne and satellite-based observations of lightning and of NOx and related species in the atmosphere. Relevant data available from measurements in regions with strong LNOx influence are identified, including recent observations at midlatitudes and over tropical continents where most lightning occurs. Various methods to model LNOx at cloud scales or globally are described. Previous estimates are re-evaluated using the global annual mean flash frequency of 44±5 s−1 reported from OTD satellite data. From the review, mainly of airborne measurements near thunderstorms and cloud-resolving models, we conclude that a "typical" thunderstorm flash produces 15 (2–40)×1025 NO molecules per flash, equivalent to 250 mol NOx or 3.5 kg of N mass per flash with uncertainty factor from 0.13 to 2.7. Mainly as a result of previous global model studies for various LNOx parameterisations tested with related observations, the best estimate of the annual global LNOx nitrogen mass source and its uncertainty range is (5±3) Tg a−1 in this study. An accuracy of order 1 Tg a−1 or 20%, as necessary in particular for understanding tropical tropospheric chemistry, is still a challenging goal.

Aspects of the chemistry of ozone depletion

1979 ◽  
Vol 290 (1376) ◽  
pp. 505-514 ◽  
Keyword(s):  
Nitrogen Oxides ◽  
Chemical Reactions ◽  
Ozone Depletion ◽  
Atomic Oxygen ◽  
Stratospheric Ozone ◽  
Considerable Effect ◽  
Laboratory Studies ◽  
Trace Species ◽  
Halogen Compounds ◽  
Anthropogenic Nitrogen

The conversion of stratospheric ozone and atomic oxygen back to molecular oxygen is catalysed by a number of atmospheric trace species such as nitrogen oxides (NO, NO 2 ), halogen (Cl, ClO) and hydrogen (H, HO, HO 2 ) radicals. The concentrations of these species are interrelated by a complex series of chemical reactions where those of hydroperoxy (HO 2 ) are the least well understood. Recent direct laboratory studies of the reactions of HO 2 have a considerable effect on estimates of ozone depletion by anthropogenic nitrogen oxides and halogen compounds.

scholarly journals Attributing land transport emissions to ozone and ozone precursors in Europe and Germany

2019 ◽  
Author(s):  
Mariano Mertens ◽  
Astrid Kerkweg ◽  
Volker Grewe ◽  
Patrick Jöckel ◽  
Robert Sausen
Keyword(s):  
Carbon Monoxide ◽  
Nitrogen Oxides ◽  
Tropospheric Ozone ◽  
Seasonal Cycle ◽  
Emission Inventory ◽  
Ground Level ◽  
Global Model ◽  
Ozone Precursors ◽  
Po Valley ◽  
Transport Emissions

Abstract. Land transport is an important emission source of nitrogen oxides, carbon monoxide and volatile organic compounds, which serves as precursors for tropospheric ozone. Besides the direct negative impact of nitrogen oxides, air quality is also affected by these enhanced ozone tropospheric ozone concentrations. As ozone is radiativly active, its increase contributes to climate change. Due to the strong non-linearity of the ozone chemistry, the contribution of land transport emissions to tropospheric ozone cannot be calculated or measured directly, instead atmospheric-chemistry models equipped with specific source apportionment methods (called tagging) are required. In this study we investigate the contributions of land transport emissions to ozone and ozone precursors using the MECO(n) model system, coupling a global and a regional chemistry climate model, which are equipped with a tagging diagnostic. For the first time the effects of long range transport and regional effects of regional emissions are investigated. This is only possible by applying a tagging method simultaneously and consistently on the global and regional scale. We performed two three-year simulations with different anthropogenic emission inventories for Europe by applying our global model with two regional refinements, i.e. a European nest (50 km resolution) in the global model and a German nest (12 km resolution) in the European nest. We find contributions of land transport emissions to reactive nitrogen (NOy) near ground-level in the range of 5 to 10 nmol mol−1, corresponding to 50 to 70 % of the ground level NOy values. The largest contributions are around Paris, Southern England, Moscow, the Po Valley, and Western Germany. Carbon monoxide contributions range from 30 nmol mol−1 to more than 75 nmol mol−1 near emission hot spots such as Paris or Moscow. The contribution of land transport emissions to ozone show a strong seasonal cycle which absolute contributions of 3 nmol mol−1 during winter and 5 to 10 nmol mol−1 during summer. This corresponds to relative contributions of 8 to 10 % during winter and up to 16 % during summer. Those largest values during summer are confined to the Po Valley, while the contribution in Western Europa ranges from 12 to 14 %. The ozone contributions are robust. Only during summer the ozone contributions are slightly influenced by the emission inventory, but these differences are smaller than the range of the seasonal cycle of the contribution. This cycle is caused by a complex interplay of seasonal cycles of other emissions (e.g. biogenic) and seasonal difference of the ozone regimes. This small difference of the ozone contributions due to the emission inventory is remarkable as the precursor concentrations (NOx and CO) are much more affected by the change. In addition, our results suggest that during events with large ozone values the contribution of land transport emissions and biogenic emissions increase strongly. Here, the contribution of land transport emission peak up to 28 %. Hence, land transport is an important contributor to events of large ozone values.

scholarly journals The global lightning-induced nitrogen oxides source

2007 ◽  
Vol 7 (14) ◽  
pp. 3823-3907 ◽  
Author(s):  
U. Schumann ◽  
H. Huntrieser
Keyword(s):  
Nitrogen Oxides ◽  
Climate Changes ◽  
Tropospheric Chemistry ◽  
Laboratory Studies ◽  
Mass Source ◽  
Uncertainty Range ◽  
Airborne Measurements ◽  
Model Studies ◽  
Best Estimate ◽  
Global Flash

Abstract. The knowledge of the lightning-induced nitrogen oxides (LNOx) source is important for understanding and predicting the nitrogen oxides and ozone distributions in the troposphere and their trends, the oxidising capacity of the atmosphere, and the lifetime of trace gases destroyed by reactions with OH. This knowledge is further required for the assessment of other important NOx sources, in particular from aviation emissions, the stratosphere, and from surface sources, and for understanding the possible feedback between climate changes and lightning. This paper reviews more than 3 decades of research. The review includes laboratory studies as well as surface, airborne and satellite-based observations of lightning and of NOx and related species in the atmosphere. Relevant data available from measurements in regions with strong LNOx influence are identified, including recent observations at midlatitudes and over tropical continents where most lightning occurs. Various methods to model LNOx at cloud scales or globally are described. Previous estimates are re-evaluated using the global annual mean flash frequency of 44±5 s−1 reported from OTD satellite data. From the review, mainly of airborne measurements near thunderstorms and cloud-resolving models, we conclude that a "typical" thunderstorm flash produces 15 (2–40)×1025 NO molecules per flash, equivalent to 250 mol NOx or 3.5 kg of N mass per flash with uncertainty factor from 0.13 to 2.7. Mainly as a result of global model studies for various LNOx parameterisations tested with related observations, the best estimate of the annual global LNOx nitrogen mass source and its uncertainty range is (5±3) Tg a−1 in this study. In spite of a smaller global flash rate, the best estimate is essentially the same as in some earlier reviews, implying larger flash-specific NOx emissions. The paper estimates the LNOx accuracy required for various applications and lays out strategies for improving estimates in the future. An accuracy of about 1 Tg a−1 or 20%, as necessary in particular for understanding tropical tropospheric chemistry, is still a challenging goal.

scholarly journals Improvement of Working Conditions of Mining Workers by Reducing Nitrogen Oxide Emissions during Blasting Operations

2021 ◽  
Vol 11 (21) ◽  
pp. 9969
Author(s):  
Marat Rudakov ◽  
Ruslan Babkin ◽  
Ekaterina Medova
Keyword(s):  
Nitrogen Oxides ◽  
Nitrogen Oxide ◽  
National Standards ◽  
Pentaerythritol Tetranitrate ◽  
Laboratory Studies ◽  
Nitrogen Oxide Emissions ◽  
Zinc Carbonate ◽  
Highly Active ◽  
Maximum Permissible Concentrations ◽  
The Impact

The article presents comparison of the values of maximum permissible concentrations, revealed during the analysis of the national standards of Russia and Australia in the field of regulation of nitrogen oxides. The impact of poisoning of the workers of the quarry with nitrogen oxides after blasting operations are presented. A detailed review of studies of methods for reducing nitrogen oxide emissions is given. The way of decreasing emission of nitrogen oxides using highly active catalysts as a part of the profiled tamping is offered. Laboratory studies were carried out using a model explosive and pentaerythritol tetranitrate. The results obtained showed that zinc carbonate (ZnCO3) is the most effective. The reduction in the amount of nitrogen oxide emissions was 40% of that released during experiments without the addition of catalysts.

scholarly journals Role of nitrogen oxides in the stratosphere: A reevaluation based on laboratory studies

1999 ◽  
Vol 26 (15) ◽  
pp. 2387-2390 ◽  
Author(s):  
Robert W. Portmann ◽  
Steven S. Brown ◽  
Tomasz Gierczak ◽  
Ranajit K. Talukdar ◽  
James B. Burkholder ◽  
...  
Keyword(s):  
Nitrogen Oxides ◽  
Laboratory Studies

Hydrogen Cyanide Polymers from the Impact of Comet P/Shoemaker-Levy 9 on Jupiter

1997 ◽  
Vol 161 ◽  
pp. 179-187
Author(s):  
Clifford N. Matthews ◽  
Rose A. Pesce-Rodriguez ◽  
Shirley A. Liebman
Keyword(s):  
Amino Acids ◽  
Solar System ◽  
Hydrogen Cyanide ◽  
Nitrogen Heterocycles ◽  
Laboratory Studies ◽  
Heterogeneous Solids ◽  
The Many ◽  
Comet Halley ◽  
The Impact ◽  
By Products

AbstractHydrogen cyanide polymers – heterogeneous solids ranging in color from yellow to orange to brown to black – may be among the organic macromolecules most readily formed within the Solar System. The non-volatile black crust of comet Halley, for example, as well as the extensive orangebrown streaks in the atmosphere of Jupiter, might consist largely of such polymers synthesized from HCN formed by photolysis of methane and ammonia, the color observed depending on the concentration of HCN involved. Laboratory studies of these ubiquitous compounds point to the presence of polyamidine structures synthesized directly from hydrogen cyanide. These would be converted by water to polypeptides which can be further hydrolyzed to α-amino acids. Black polymers and multimers with conjugated ladder structures derived from HCN could also be formed and might well be the source of the many nitrogen heterocycles, adenine included, observed after pyrolysis. The dark brown color arising from the impacts of comet P/Shoemaker-Levy 9 on Jupiter might therefore be mainly caused by the presence of HCN polymers, whether originally present, deposited by the impactor or synthesized directly from HCN. Spectroscopic detection of these predicted macromolecules and their hydrolytic and pyrolytic by-products would strengthen significantly the hypothesis that cyanide polymerization is a preferred pathway for prebiotic and extraterrestrial chemistry.

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