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DLR Lab tests 7 March 2011 Eyjafjalla ground samples. Diluter 1/100. Separator of sample lines (Flow rate : 2.6 – 3.2 l/min). Bottle for ash particles mixing. Grimm/OPC. Polar Nephelometer. Exhaust tube connected to pump. FIRST RUN (12:18 – 12:54). 10 4.
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DLR Lab tests 7 March 2011 Eyjafjalla ground samples Diluter 1/100 Separator of sample lines (Flow rate : 2.6 – 3.2 l/min) Bottle for ash particles mixing Grimm/OPC Polar Nephelometer Exhaust tube connected to pump
FIRST RUN (12:18 – 12:54) 104 Grimm part. conc. (l-1 mm-1) 0 Total Particle concentration (GRIMM data)
Interpretation of the PN measured optical properties Inversion model developed by Dubovik et al. (2006) for aerosol (AERONET) and adapted to contrail and ash particles by V. Shcherbakov (LaMP) ● Measurements : Scattering phase function (PN) ● Retrieved parameters : - Refractive index (real and imaginary components) - Particle size distribution - Distribution of spherical / aspherical particle ratio (SAR) Aspherical particles = mixture of oblate / prolate spheroids (0.5 / 1.5 aspect ratios). ● Validation of the results : - FSSP-300 / FSSP-100 / Grimm particle size distribution
DLR Lab tests 7 March 2011 Eyjafjalla ground samples Grimm Extret. = 1.36 km-1 gret. = 0.70 n = 1.49 + 0.0005 i Spherical / aspherical partitioning (SAR) = 32% 32% of spherical particles and 68% of aspherical particles
30 September 2011 Flight Stromboli & Etna plume measurements
30 / 09 / 2011 1 Etna Loatitude (°N) 3 2 4 Longitude (°E)
30 / 09 / 2011 Altitude (m) Ext PN (km-1) Asym. parameter N(0.5) N(3) Ext T (km-1) Deff (mm) Etna_1 Stromboli Etna_2 Etna_3 Etna_4 TIME (UTC)
Etna upper plume Etna lower plume Stromboli
Nb of occurences Asymmetry parameter Asymmetry parameter
Etna_2-4 upper plume Etna_1-3 lower plume Altitude (m) Stromboli 0.75 0.77 0.79 0.81 0.83 Asymmetry parameter
Upper plume Lower plume Etna plumes
30/09/2012 7:10:00 – 7:14:30 UT Stromboli plume Alt = 975 m T = 17.2°C RHw = 40% Measurements (PN) Best fit Retrived SSP-300 FSSP-100 C(0.5) = 27 cm-3 C(3) = 0.2 cm-3 M = 0.01 mg/m3 Ext = 0.09 km-1 Deff = 1.4 mm g = 0.784 n = 1.34 + 0.0005 i 100% spherical particles ( Residual = 7%)
Etna lower plume 30/09/2012 7:28:00 – 7:35:30 UT Alt = 3520 m T = 1.2°C RHw = 12% Measurements (PN) Best fit Retrived SSP-300 FSSP-100 C(0.5) = 50 cm-3 C(3) = 0.2 cm-3 Ext = 0.10 km-1 M = 0.03 mg/m3 Deff = 1.9 mm g = 0.793 n = 1.34 + 0.0005 i 100% spherical particles ( Residual = 7%)
Etna upper plume 30/09/2012 7:29:30 – 7:37:00 UT Alt = 3660 m T = 0.5°C RHw = 12% Measurements (PN) Best fit Retrived SSP-300 FSSP-100 C(0.5) = 28 cm-3 C(3) = 0.8 cm-3 Ext = 0.17 km-1 M = 0.04 mg/m3 Deff = 2.4 mm g = 0.774 n = 1.36 + 0.0005 i 100% spherical particles ( Residual = 8%)
Summary of results Refractive indexes n c ● Concert2 Stromboli plume (30/09/2011) 1.34 0.0005100% spherical ● Concert2 Etna upper plume (30/09/2011) 1.34 0.0005 100% spherical ● Concert2 Etna lower plume (30/09/2011) 1.36 0.0005 100% spherical ● DLR lab tests Eyjafjalla ground samples 1.49 0.0005 ~ 70% aspherical ● Eyjafjalla plume Schumann et al., 2011 1.59 0.004 – 0.008 - ● Eyjafjalla PlumeJohnson et al. 2012 1.52 0.0015 -