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Pollution transported to the Arctic during the POLARCAT-France spring and summer campaigns: source regions and aerosol properties
B. Quennehen1, A. Schwarzenboeck1, A. Matsuki2, J. Schmale3, H. Sodemann4*, J. Schneider3, G. Ancellet5, A. Stohl4, J. Pelon5
and K. Law5EGU2011 - 10962
XY50
3. SPRING CAMPAIGNA. European anthropogenic plume sample 3 consecutive days B. Asian anthropogenic and fire plumes
101 102 103 10410
100
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103
104
R2 = 0.982R2 = 0.992R2 = 0.976
Diameter (nm)
Con
cent
ratio
ns d
N/d
logD
(#.c
m)
Asian anth. meas.Asian anth. fitAsian fires meas.Asian fires fitBackground meas.Background fit
4. SUMMER CAMPAIGN
1. CONTEXT
1 Laboratoire de Météorologie Physique (LaMP), Université Blaise Pascal, Clermont-Ferrand, France.2 Frontier Science Organisation, Kanazawa University, Japan.3 Particle chemistry dept., Max Planck Institute for Chemistry, Mainz, Germany.4 Norwegian Institute for Air Research, Kjeller, Norway.5 LATMOS-IPSL, UPMC Univ-Paris 6; Univ. Versailles St-Quentin; CNRS/INSU, UMR 8190, Paris, France.*now at Instiute for Atmospheric and Climate Science, ETH, Zürich, Switzerland.
5. SUMMARY
Polar regions are known to be more strongly impacted by global warming than other regions (IPCC, 2007). Previous studies on climate related processes in the Arctic atmosphere were mostly based on surface observations and many advances in measurement techniques were done since the previous airborne campaigns.
2. INSTRUMENTATIONPhysical properties:• Scanning Mobility Particle Sizer (SMPS)• Optical Particle Counter (OPC Grimm,TSI and PCASP 100-X, DMT)• Condensation Particle Counter (CPC 3010 & 3025, TSI)Chemical properties:• Aerodyne time of flight aerosol mass spectrometer (C-ToF-AMS, MPI, Mainz)• 2 stage cascade impactor (sub and super-micronic) + a posteriori spectros-copy and microscopy analyses (FSO, Kanazawa)• Gas phase: CO and O3 measurements (Mozart, LATMOS, Paris)Optical properties: • 1λ Particle Soot Absorption Photometer (PSAP, TSI)• 3λ Nephelometer (TSI)• Aerosol Lidar (LNG, LATMOS, Paris)
101 102 103 10410
100
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104
R2 = 0.991R2 = 0.984
R2 = 0.976
R2 = 0.988R2 = 0.992R2 = 0.992R2 = 0.983
Diameter (nm)
Con
cent
ratio
ns d
N/d
logD
(#.c
m)
9 April meas.9 April fit10 April meas.10 April fit11 April meas.11 April fitBackground meas.Background fit
Fig. 3d
3 4 5 6 7 8 9 1020
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FLEXPART age (days)
Aitk
en m
ode
mea
n di
amet
er (n
m)
R2 = 0.91y = 14.4 exp(t/6.3)
Flight 33 (04/09)Flight 34 (04/10)Flight 35 (04/11)Exponential fit
4.6 5.3 6.5 7 7.6 7.80
1
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Flexpart age (days)
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rptio
n co
effic
ient
(m)
R2 = 0.78
4.7 5.3 6.6 7.1 7.6 7.820
40
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Flexpart age (days)
R2 = 0.53
Fig. 3a Fig. 3b Fig. 3c
Dia
met
er (n
m) Altitude (m
)
Concentration dN/dlogD (#/cm3)
SMPS
OPC
Fig. 3f
500 nm
Soot-like inclusion
Mineral
Microscopy
Spectroscopy
Det
ectio
n Fr
eq. (
%)
TEM-EDX of indi-vidual submicron pollution particles
Fig. 3g
• Asian pollution air mass encountered.• Lidar backscattering signal enhanced between 3 and 4 km above sea level (Figure 3e).• The aircraft passed through the pollu-ted layer where aerosol size distribution measurements reveal enhanced concentrations and variations in the mean diameter of the accumulation mode (Fig. 3f and 3g).• Anthropogenic origin for the first part of the layer (boarded in red in Fig. 3e) while the second part (boarded in green), originated from biomass burning (found from optical properties studied by De Villiers et al. (2010,[2]).• Microscopy images and spectroscopy analyses of in-situ submicron aerosol samples collected during the flight (for the anthropogenic origin, Fig. 3h and 3i).
Fig. 3e
Fig. 3h
Fig. 3i
• North American boreal forest fires (BFF) particles trans-ported to Greenland sampled.• Sulphate and organic mass concentration evolutions (Fig. 4a, red and green, respectively) measured by the AMS as well as the refractory mass (in black).• Temporal evolution of aerosol size distributions (Fig. 4b).• Mean aerosol size distributions related to BFF (from 3 POLARCAT flights) are compared to previous measure-ments of BFF performed by Petzold et al. (2007,[3]) and Fiebig et al. (2003,[4]) in Fig. 4c.• Findings in correlation with Schmale et al. (2011,[5]).
120 ° W
105 ° W
90° W 75° W 60° W
45° W
30° W
30 ° N
45 ° N
60 ° N
75 ° N
Total precipitation (mm)5 4 3 2 1 0
120 ° W
105 ° W
90° W 75° W 60° W
45° W
30° W
30 ° N
45 ° N
60 ° N
75 ° N
RH (%)100 80 60 40 20 0
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Fig. 4b
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Fig. 4c
• Selected flight periods are related to enhanced CO mixing ratio (Fig. 4d) and higher values of the light absorption coefficient.• Elevated values of the volatilized volume fraction (Fig. 4e) are found (0.78 for this flight), thus indicating that a large part of particles were coated. • The accumulation mode measured during the POLARCAT-sum-mer campaign is less pronounced than observed during the other studies (Fig. 4c). This difference can be explained by wet scaven-ging occuring along the transport pathway of pollution particles from the source regions to Greenland. Fig. 4f and 4g are presenting ECMWF relative humidity (%) and total precipitation (mm) along the Hysplit back-trajectories.
13:00 13:30 14:00 14:30 15:00 15:30 16:0050
100
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Fig. 4d
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Fig. 4f Fig. 4g
ACKNOWLEDGMENTS:The author would like to thank the French research agencies ANR, CNES, CNRS-INSU and IPEV as well as EUFAR. We acknowledge funding by the German Research Foundation (DFG) through the SPP 1294, by the state «Exzellenzcluster Geocycles» of Rheinland-Pfalz, and by the Max Planck Society. NILU researchers were supported by the Norwegian Research Council in the framework of POLARCAT-Norway and CLIMSLIP. We also would like to thank SAFIRE and Christophe Gourbeyre for their support during the planning and exe-cution of the French ATR-42 campaigns and, together with DT-INSU, for help with instrument integration.
[1] Stohl, A., Forster, C., Frank, A., Seibert, P. and Wotawa, G.: Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2, Atmos. Chem. Phys., 5, 2461-2474, doi: 10.5194/acp-5-2461-2005, 2005.[2] De Villiers, R. A., Ancellet, G., Pelon, J., Quennehen, B., Schwarzenboeck, A., Gayet, J. F. and Law, K. S.: Airborne measurements of aerosol optical properties related to early spring transport of mid-latitude sources into the Arctic, Atmos. Chem., Phys.,10, 5011-5030, doi:10.5194/acp-10-5011-2010,2010.[3] Petzold, A., Weinzierl, B., Huntrieser, H., Stohl, A., Real, E.,Cozic, J., Fiebig, M., Hendricks, J., Lauer, A., Law, K. S., Roiger, A., Schlager, H. and Weingartner, E.: Perturbation of the European free troposphere aerosol by North American forest fire plumes during the ICARTT-ITOP experiment in summer 2004, Atmos. Chem. Phys, 7, 5105-5127, doi: 10.5194/acp-10-5105-2007, 2007.[4] Fiebig, M., Stohl, A., Wendish, M., Eckhardt, S., and Petzold, A.: Dependence of solar radiative forcing of forest fire aerosol on ageing and state of mixture, Atmos. Chem. Phys., 3, 881-891, doi: 10.5194/acp-3-881-2003, 2003.[5] Schmale, J., Schneider, J., Ancellet, G., Quennehen, B., Stohl, A., Sodemann, H., Burkhart, J., Hamburger, T., Arnold, S. R., Schwarzenboeck, A., Borrmann, S. and Law, K. S.: Source identification and airborne chemical characterisation of aerosol pollution from long-range transport over Greenland during POLARCAT summer campaign 2008, Atmos. Chem. Phys. Discuss., 11, 7593-7658, doi: 10.5194/acpd-11-7593-2011, 2011.
• Ageing of an European anthropogenic air mass is related to the increase of the mean diameter (from 33 to 51 nm) of the Aitken mode, while its concentration decreased from 860 to 165 particles/cm3. The air mass evo-lution is also seen in the decrease of the CO mixing ratio and of the light absorption coefficient (related to black carbon concentration). Since aero-sol volatility is constant during the 3 days, the Aitken mode growth is mainly due to particle coagulation.• Asian plumes contain very low concentration of Aitken mode particles while accumulation mode particles (and to a lower extent coarse mode) were enhanced. TEM-EDX analyses gave qualitative informations on the origin of pollution particles. Soot is present in more than 20% of the ana-lysed particles.
contact: [email protected]
• North American boreal forest fire particles transported to the Arctic were studied. Enhancement in CO mixing ratio, and sulphate and organics mass concentration were coupled to these air masses. Absorbing particles were mostly found in the Aitken mode while coated particles composed the accumulation mode.• The concentration of the accumulation mode particles was very low compared to previous studies. The difference is explained by potential wet scavenging occuring on the pathway of the air masses from the source re-gions to Greenland.
SPR
ING
SUM
MER
• 4th International Polar Year• POLARCAT project lauched to study long-range transport of short-lived pollutant (particulates and gases) to the Arctic.• 12 flights out of Kiruna, Sweden, April 2008.• 12 flights out of Kangerlussuaq, Greenland, July 2008.
• Air mass origins along the flight tracks were determined from the analysis with the Lagrangian dispersion model FLEXPART [1] (Fig. 3e).• Anthropogenic air mass from Central Europe sampled 3 consecutive days (9, 10 and 11 April).• Air mass ageing characterisation by exponential decrease of both CO mixing ratio and light ab-sorption coefficient (i.e., BC concentrations). see Fig. 3a and 3b.• Aerosol size distributions measured and log-normally fitted in Fig. 3d.• Increase of the Aitken mode mean diameter and decrease of its concentration evident (Fig. 3c)
Fig. 3e
9 April 10 April 11 April
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