 |
| Titel |
Multi-annual changes of NOx emissions in megacity regions: nonlinear trend analysis of satellite measurement based estimates |
| VerfasserIn |
I. B. Konovalov, M. Beekmann, A. Richter, J. P. Burrows, A. Hilboll |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 10, no. 17 ; Nr. 10, no. 17 (2010-09-08), S.8481-8498 |
| Datensatznummer |
250008761
|
| Publikation (Nr.) |
 copernicus.org/acp-10-8481-2010.pdf |
|
|
|
|
|
| Zusammenfassung |
| Hazardous impact of air pollutant emissions from megacities on atmospheric
composition on regional and global scales is currently an important issue in
atmospheric research. However, the quantification of emissions and related
effects is frequently a difficult task, especially in the case of developing
countries, due to the lack of reliable data and information. This study
examines possibilities to retrieve multi-annual NOx emissions changes
in megacity regions from satellite measurements of nitrogen dioxide and to
quantify them in terms of linear and nonlinear trends. By combining the
retrievals of the GOME and SCIAMACHY satellite instrument data with
simulations performed by the CHIMERE chemistry transport model, we obtain
the time series of NOx emission estimates for the 12 largest urban
agglomerations in Europe and the Middle East in the period from 1996 to
2008. We employ then a novel method allowing estimation of a nonlinear trend
in a noisy time series of an observed variable. The method is based on the
probabilistic approach and the use of artificial neural networks; it does
not involve any quantitative a priori assumptions. As a result,
statistically significant nonlinearities in the estimated NOx emission
trends are detected in 5 megacities (Bagdad, Madrid, Milan, Moscow and
Paris). Statistically significant upward linear trends are detected in
Istanbul and Tehran, while downward linear trends are revealed in Berlin,
London and the Ruhr agglomeration. The presence of nonlinearities in
NOx emission changes in Milan, Paris and Madrid is confirmed by
comparison of simulated NOx concentrations with independent air quality
monitoring data. A good quantitative agreement between the linear trends in
the simulated and measured near surface NOx concentrations is found in
London. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|