Troposphere ozone analysis

Triterpenes, structural chemistry, 136 Tropopause, emissions model, 605 Troposphere ozone analysis, 605 trifluoromethyl peroxynitrate, 743 Tryptophan... 

Example of an analysis of exhaust gas by gas phase chromatography and j relative reactivity of effluents with respect to tropospheric ozone formation. I... 

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

These studies stimulated the investigation of the use of TOMS data for the determination of the tropospheric ozone column amount by related techniques. Hudson, Thompson and co-workers have developed and refined a technique called the tropical tropospheric ozone (TTO) method (Hudson et al., 1995 Kim et al., 1996 Hudson and Thompson, 1998). This technique utilises a Fourier analysis to identify the range of latitudes for which the method is applicable by using the recognition of a planetary wave pattern to estimate stratospheric and background tropospheric ozone. 

The most promising prospect for estimation and prediction of anthropogenic SAT changes has to do with an analysis of the spatiotemporal variability of SAT fields, which takes into account the impacts of the greenhouse effect and aerosols. Realization of this approach is seriously complicated, however, by the impossibility of reliably assigning the aerosol forcing on the SAT field. Another serious problem is the necessity to take into account the impact on climate of changes in the content of stratospheric and tropospheric ozone. 

There is growing evidence that the composition of the troposphere is changing. For example, analysis of historical ozone records has indicated that tropospheric ozone levels in both hemispheres have increased by a factor of 3-A over the last century. Methane concentrations have effectively doubled over the past 150 years and N2O levels have risen by 15% since pre-industrial times.Measurements of halocarbons have shown that this group of chemically and radiatively important gases to be increasing in concentration until relatively recently. 

Rasmussen A., Kiilisholm S., Sprensen J. H., and Mikkelsen I. S. (1997) Analysis of tropospheric ozone measurements in Greenland. Tellus 49B, 510-521. 

Mauersberger (1981), utilizing in situ mass spectrometric measurements, demonstrated that ozone possesses a large 0 enrichment. The O isotopic composition was not determined and the mass-independent isotopic composition could not be detected. As reviewed by Thiemens (1999), Weston (1999), and Johnston and Thiemens (2003), there now exists an extensive literature on stratospheric ozone isotopic measurements obtained by different techniques. Measurements by Mauersberger (1987) confirmed that stratospheric ozone was mass-independently fractionated as displayed in the 1983 laboratory experiments of Thiemens and Heidenreich. Return ozone isotopic analysis by Schueler et al. (1990) demonstrated that stratospheric ozone possessed an isotopic composition entirely consistent with laboratory observations. Tropospheric ozone has also been studied for its 5 0 isotopic... 

Lippmann M (1993) Health effects of tropospheric ozone Review of recent research findings and their implications to ambient air quality standards. Journal of Exposure Analysis and Environmental Epidemiology 3 103-129. 

As governmental bodies, the Ministries of Environment are the competent authority for the majority of activities related to environmental issues such as trans-boundary air and water pollution, troposphere ozone and climate change, for instance. The main task of a ministry on these issues is therefore to elaborate and implement the environment policy. As it is nearly everywhere within the Member States of the European Union, the ministries carry out only a few studies and analysis by themselves, but a lot of routine work is allocated to different administrations or institutions. This approach was not followed in some countries of the 10 and the research and international collaboration on different environmental programmes suffered for a... 

Staehelin, J., and Schmid, W. (1991) Trend analysis of tropospheric ozone concentrations utilizing the 20-year data set of balloon soundings over Payeme (Switzerland), Atmos. Environ. 25A, 1739-1749. 

FIGURE 2.13 Selected annual means of ozone balloon soundings over Payerne, Switzerland (Staehelin and Schmid, 1991). The annual mean altitude of the tropopause at Payerne is about 10 km, varying from about 8 km in winter to 12 km in summer. (Reprinted from Atmos. Environ., 25A, Staehelin, J. and Schmid, W., Trend analysis of tropospheric ozone concentrations utilizing the 20-year data set of balloon soundings over Payerne (Switzerland), p. 1739,1991, with kind permission from Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington 0X5 1GB, UK.)... 

The Canadian stations show decreases or insignilicant trends for 1970-19% and decreases of —2 to —8% per decade in the mid-troposphere in the period of 1980 to 1996. A more recent update including measurements until 1999 reveals less negative tropospheric ozone trends caused by a considerable increase in tropospheric ozone since 1993. The data analysis further indicates a strong correlation between ozone in the lower stratosphere and in the troposphere. This finding suggests that stratospheric ozone depletion causing a decrease in the amount of ozone transported from the stratosphere into the troposphere was possibly an important contribution to the tropospheric decrease of the measurements since 1980. 

Reactions that simnlate tropospheric conditions have been carried ont in Teflon bags with volumes of ca. 6 m htted with sampling ports for introduction of reactants and snbstrates, and removal of samples for analysis. Substrates can be added in the gas phase or as aerosols that form a surface him. The primary reactants are the hydroxyl and nitrate radicals, and ozone. These mnst be prepared before use by reactions (a) to (c). 

The model tropopause is defined by a PV level of 3.5 pvu poleward of 20° latitude, and by a -2 K km 1 temperature lapse rate equatorward of 20° latitude. Consequently, in this study the troposphere is defined as the volume between the surface and the simulated tropopause. Because the model does not consider typical stratospheric chemical reactions explicitly, ozone concentrations are prescribed from 1-2 levels above the model tropopause up to the top of the model domain at 10 hPa. In both hemispheres we apply monthly and zonally averaged distributions from a 2D stratospheric chemistry model [31]. In the present version of the model, we use the simulated PV and the regression analysis of the MOZAIC data (Section 2) to prescribe ozone in the NH extratropical lower stratosphere, which improves the representation of ozone distributions influenced by synoptic scale disturbances [32, 33]. Furthermore, the present model contains updated reaction rates and photodissociation data [34]. 

Kim, J.-H., R.D. Hudson and A.M. Thompson (1996) A new method for deriving time averaged tropospheric column ozone over die tropics using total ozone monitoring spectrometer (TOMS) radiances intercomparison and analysis using TRACE A data. Journal of Geophysical Research 101 24317-24330. 

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