ISSN:
1573-0662
Keywords:
Tropospheric photochemistry
;
odd nitrogen
;
asteroid impacts
;
ozone depletion
;
climatic change
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
Notes:
Abstract Previous zero-dimensional photochemical calculations indicate that multiple tropospheric steady states may exist, in which different NO x (≡NO+NO2) levels could be supported by the same source of NO x . To investigate this possibility more closely, a one-dimensional photochemical model has been used to estimate the rate of removal of atmospheric NO x compounds at different NO x levels. At low NO x levels NO x is photochemically converted to HNO3, which is removed by either wet or dry deposition. At high NO x levels formation of HNO3 is inhibited, and NO x is removed by a variety of other processes, including rainout of N2O4 and N2O5, surface deposition of NO and NO2, and direct dissolution of NO and NO2 in rainwater. Multiple steady states are possible if surface deposition of NO x is relatively inefficient. The NO x source required to trigger high atmospheric NO x levels is approximately 10 to 15 times the present global emission rate-less than half the source strength predicted by the zero-dimensional model. NO x mixing ratios in excess of 10-7 would cause severe damage to the ozone layer and could result in either a climatic warming or cooling, depending upon the amount of NO2 present.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00122522
