Nucleation airborne measurements ATR42 Anas Culot 4 th

Nucleation : airborne measurements (ATR-42) Anaïs Culot 4 th International Workshop Charmex

SAF-Med 2013 ERSA MAJORCA Marchand Pey

Event July 30: N 3 -10 nm Backward trajectories : - N 3 -10 = Concentration of particles between 3 – 10 nm - More particles near the coast - More particles at high altitude (3400 m) than in BL (215 m) Air masses from the continent before reaching Ersa/plane Nucleation advected from the continent

Event July 30: larger particles in the nucleation mode d. N/dlog(dp) Diameter (nm) - More particles near the coast (in blue) - No growth of the N 3 -10 nm particles beyond 20 nm during the flight

Event August 1 : N 3 -10 nm Backward Trajectories : - North / Northeast origin - Air masses flew over Ersa before reaching the airplane - Low altitude : 500 m - High concentrations all along the flight

Event August 1 : larger particles in the nucleation mode ERSA ATR -Distinct growth of small particles in Ersa - Ultrafine particles also detected in the plane

Event August 1 MODE Nuc MODE Aitken MODE Acc - Decrease of the nucleation mode diameter when the plane moves away from Ersa - Concentrations of nucleation mode roughly steady Nucleation mode « alimented » by new particles which were too small to be measured by the SMPS in Ersa : - 3 -10 nm particles measured - Deacreasing of the diameter of the particles in the plane FNP above the sea

SAF-Med 2014 Flight No. Date Objective C-To. F-AMS SMPS CPC 5 nm CPC 10 nm Nucléation Flight 15 29/06/14 Pollution Flight 16 30/06/14 Biogenic Flight 17 01/07/14 Pollution Flight 18 & 02/07/14 19 Pollution High Altitude (3000 -3500) Flight 20 03/07/14 Biogenic - Flight 21 05/07/14 Biogenic High altitude (3000) Flight 22 06/07/14 Pollution Flight 23 08/07/14 Biogenic Flight 24 08/07/14 Pollution Flight 26 10/07/14 Marine Low troposphere (Inf 1000 m) Alt et BL Low altitude • Faulty data. (For the AMS: Mainly high altitude measurements so instrument was close to the detection limit approx 90% of the time. ) • Data OK. Preliminary analysis performed

Marine flight High concentrations of fine particles

Marine flight N 5 -10 nm N 20 -50 nm

Vertical sonding N 5 -10 nm • Nucleation particles more concentrated between 1000 -1300 m • Layer correlated with high concentrations of organics

Conclusions - Nucleation events measured by the plane : ground station during favorable periods for the process. - Large spatial extension on the North-West Mediterranean basin - Ultrafine Particules (3 -10 nm) detected at high altitude but low growth - In Marine Boundary Layer, it seems that a transport of small particles from the continent overlaps with nucleation above the sea - Correlation between organics and ultrafine particles at 1000 -1300 m

Perspectives Event August 1 : N 3 -10 nm DMS? Gaseous precursors (PTR-MS)