Ozone budget

Besides NOx oxides, there is nitrous oxide (N2O), which is of special interest in isotope geochemistry. N2O is present in air at around 300 ppb and increases by about 0.2% per year. Nitrous oxide is an important greenhouse gas that is, on a molecular basis, a much more effective contributor to global warming than CO2 and that is also a major chemical control on stratospheric ozone budgets. 

Wang, Y J. A. Logan, and D. J. Jacob, Global Simulation of Tropospheric 03-NOA-Hydrocarbon Chemistry. 2. Model Evaluation and Global Ozone Budget, J. Geophys. Res., 103, 10727-10755 (1998). 

Laboratory measurements (17) next showed that reaction R19 proceeded about 40 times faster than determined earlier, strongly promoting ozone production and increasing HO concentrations with major consequences for tropospheric and stratospheric chemistry. Table I presents an ozone budget calculated with a three-dimensional chemistry transport model of the troposphere which takes into account the afore mentioned reactions. 

Tropospheric ozone budgets, globally and for the northern (NH) and southern (SH) hemisphere in unit of 1013 mole/year. Only CH4 and CO oxidation cycles were considered. Calculations were made with the global, three-dimensional MOGUNT1A model (IS). 

MODEL ANALYSIS OF STRATOSPHERE-TROPOSPHERE EXCHANGE OF OZONE AND ITS ROLE IN THE TROPOSPHERIC OZONE BUDGET... 

We simulated a period of three years (not nudged) to investigate the climatology of the tropospheric ozone budget and the contribution by STE. We focus on the NH where the ozone-PV relation derived from MOZAIC is applied. Figure 4 displays the seasonality of cross-tropopause transports, photochemical production/destruction, dry deposition and the tropospheric content of ozone. 

Gidel, L.T., and Shapiro, M.A. (1980) General circulation model estimates of the net vertical flux of ozone in the lower stratosphere and the implications for the tropospheric ozone budget, J. Geophys. Res. 85, 4049-... 

C is a term representative of the photochemistry (production or destruction), Ey the entrainment velocity, [03] the concentration of free tropospheric ozone, the dry deposition velocity and H the height of the boundary layer. The ozone budget shown in Table 8 has been calculated both in the summer and winter using the ozone continuity equation for a site in the marine boundary layer. 

JuNGE C.E., Global ozone budget and exchange between stratosphere and troposphere. Tellus, 14, 363-377 (1962). 

Monod A. and P. Carlier Impact of clouds on the tropospheric ozone budget Direct effect of multiphase photochemistry of soluble organic compounds, Atmos. Environ., 33 (1999) 4431-4446. 

It should be mentioned that in the atmospheric reservoir gases other than those listed in Table 1 can be found. For the sake of simplicity the atmospheric cycle of these gases will not be presented. However, the effect of different halogen compounds, including anthropogenic chlorofluorocarbons, on the stability of atmospheric ozone layer will be discussed, in relation to the ozone budget. 

Molecules of the type CxHyBrz produce bromine atoms upon photodissociation and oxidation, like the other halogen atoms just discussed. Unlike fluorine, the chemistry of bromine is broadly similar to that of chlorine (see Yung et al. (1980) Poulet et al. (1992) Lary (1996) and Figure 5.52) and is therefore capable of affecting the ozone budget. The production of bromine atoms is followed by the reaction... 

The tropospheric ozone budget can be calculated by global chemical transport models. Table 6.2 presents the tropospheric O3 budget of Wang et al. (1998). The budget is for the... 

Wang, Y., Logan, J. A. and Jacob, D. J. (1998) Global simulation of tropospheric 03-NOx-hydrocarbon chemistry. 2. Model evaluation and global ozone budget, J. Geophys. Res. 103(D9), 10727-10755. 

Manzerall et al. (1996) have quantified the ozone budget over remote high northern latitudes in summer using chemical and meteorological measurements between 0 and 6 km... 

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