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| Titel |
Impact of the intercontinental transport of biomass burning pollutants on
the Mediterranean Basin during the CHARMEX-GLAM airborne campaign |
| VerfasserIn |
Vanessa Brocchi, Gisele Krysztofiak, Valery Catoire, Régina Zbinden, Jonathan Guth, Laaziz El Amraoui, Bruno Piguet, François Dulac, Eric Hamonou, Philippe Ricaud |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250144248
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| Publikation (Nr.) |
 EGU/EGU2017-8053.pdf |
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| Zusammenfassung |
| The Mediterranean Basin (MB) is at the crossroad of pollutant emissions from Western and
Central Europe and of major dust sources from Sahara and Arabian deserts and thus sensitive
to climate change and air quality. Several studies (Formenti et al.,J. Geophys. Res., 2002;
Ancellet et al., Atmos. Chem. Phys., 2016) also show the impact on the MB of
long-range transport of polluted air masses. However, most of the studies have
been dedicated to biomass burning aerosols. The aim of the present study is to
show trace gases impact on the MB coming from long-range transport of biomass
burning.
The Gradient in Longitude of Atmospheric constituents above the Mediterranean basin
(GLAM) campaign in August 2014, as part of the Chemistry-Aerosol Mediterranean
Experiment (ChArMEx) project, aimed at studying the tropospheric chemical variability of
gaseous pollutants and aerosols along a West-East transect above the MB. During the GLAM
campaign, several instruments onboard the Falcon-20 aircraft (SAFIRE, INSU /
Météo-France) were deployed including an infrared laser spectrometer (SPIRIT, LPC2E)
able to detect weak variations in the concentration of pollutants.
During two flights on 6 and 10 August, increases in CO, O3 and aerosols were
measured over Sardinia at 5000 and 9000 m asl, respectively. To assess the origin
of the air masses, 20-day backward trajectories with a nested-grid regional scale
Lagrangian particle dispersion model (FLEXPART, Stohl et al., Atmos. Chem. Phys.,
2005) were calculated. Combined with emissions coming from the Global Fire
Assimilation System (GFAS) inventory (Kaiser et al., Biogeosciences, 2012), this leads to
CO biomass burning contribution to aircraft measured values. Biomass burning
emissions located in Siberia in the first case and in northern America in the second
case were identified as the cause of this burden of pollutants in the mid and upper
troposphere over the MB. By adjusting the injection height of the model and amplifying
emissions, FLEXPART was able to reproduce the contribution of those fires to CO
enhancements.
Our results show that long-range transport of biomass burning induces, at local scale, an
increase by a factor ranging from 1.7 to 3.7 with respect to O3 and CO backgrounds of ∼25
and ∼70 ppb, respectively. To assess the biomass burning effect on ozone level at regional
scale over the MB, its tropospheric increase is estimated by using the chemical transport
model MOCAGE. |
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