Stephan Borrmann Kathy Law (Univ. Paris-Jussieu) Daniel Kunkel, Joachim Curtius (Univ. of Mainz and MPIC) Ralf Weigel (Univ. Clermont-Ferrand) Silvia Viciani (INOA, Florence) G. Shur, A. Ulanovsky (CAO, Moscow, Russia) Ultrafine particles in the West African UT/LS: In-situ measurements in August 2006 during the AMMA monsoon period 2007 EGU General Assembly, AS 1.14 – 1 FR4O-001

(1) Instrument: COPAS on Russian high altitude research aircracft M-55 „Geophysica“

heated channel (250°C) -Condensable liquid: Fluorinert - 1 Hz data -  10% - isokinetic inlet < 1µm Specialized CPC type COndensation PArticle counting System unheated channel

1 Hz time series/vertical profiles up to 20 km of particle # / cm³ * for sizes > 6 nm * for size diam. > 10 nm * for size diam. > 14 nm * above 10 nm after heating to 250 °C => non volatile residue * derived: Fraction f of non volatile to total # for > 10 nm COPAS Deliverables

2 Modified FSSP-SPP100 1 Cloud Imaging Probe CIP 2 COPAS units UMAINZ/MPIC instrumentation on „Geophysica“ COPAS I COPAS II

Russian M-55 „Geophysica“ (20 km ceiling)

(2) Results: „Global“ background aerosol between potential temperatures Θ of 367 K and 460 K

TROCCINOX, SCOUT-O3, AMMA transfer flights Latitude range: 55 °N to 20 °S, Jan 2005 until Aug 2006, no major volcano eruption Marrakesh Marocco Ouagadougou Burina Faso Accra Ghana Verona Italy

Marrakech-Ouagadougou Heated 10 nm channel „Cold“ 10 nm channel Pressure hPa]

-●- n 6 TROCCINOX–Transfer Germany - Brazil -●- n 6 SCOUT – Transfer Germany - Australia Θ, altitude range ≈ 367 K to 460 K ≈ 12 km to 17 km AMMA transfer

(3) Results: Vertical profiles Mid-latitudes, Brazil, Australia, West-Africa

-●- EUPLEX- Test, Forli, 2002 ― CN, Laramie, USA, Deshler et al ● Marshal Test flight, OPH 2005 ● SCOUT-Transfer, OPH - Larnaca, 2005 ● SCOUT-Transfer, Larnaca - OPH, ●- AMMA 2006, mid-latitude flights Mid latitude vertical profiles 2002 to , 41°N °N 2002, 44°N 2005, 48°N July 2006 Remar- kably konstant from 1999 until 2006

● OPH - Larnaca ● Larnaca - Dubai ● Dubai – Hyderabad ● Hyderabad – U-Tapao ● U-Tapao - Brunei ● Brunei – Darwin ● Darwin - Brunei ● Brunei – U-Tapao ● U-Tapao – Hyderabad ● Hyderabad - Dubai ● Dubai - Larnaca ● Larnaca - OPH COPAS-data vs altitude particle sizes > 6 nm  1 µm SCOUT-O3 transfer flights Germany – Australia Nov. and Dec Tropospheric variability Stratospheric compactness

SCOUT-O3 local flights Darwin, Australia ● ● ● ● ● ● A ● B ● Contrail crossing ? COPAS-data vs altitude particle sizes > 6 nm  1 µm

● n 10 non-volatile ● n 10 total ● n 14 ● n 6 -●- median n 10 COPAS-data vs altitude particle sizes > 6 nm  1 µm AMMA local flights Ouagadougou: * Unusual increase above 450 K * Compact data with very little scatter * No nucleation particles Particle number concentration [cm³] Potential Temperature [K]

Amma Darwin Brazil Brock, 1995 Potential temperature [K] Particle mixing ratio [#/mg] Context of other tropical data from „Geophysica“: Vertical profiles Tropical Brazil, Australia, West-Africa => W. African profile IS unusual.

All AMMA flights: Red: θ = 500 K Blue: θ = 350 K „Anomaly“ also in „N 2 O space“

Except AMMA all data from Chuck Wilson, Denver University, ER-2 and WB-57 tropical measurements from 1996 onward Ultrafine particle mixing ratio [#/mg of air] Potential temperature [K] Context with other tropical data

(4) Results: nonvolatile ultrafine particles ( > 10 nm and  1 µm ) (nonvolatile) particle number above 10 nm per cm³ of air (250 °C) total particle number density > 10 nm (ambient temperature) f = nonvolatile residues ambient particles = « »

Mid latitudes ― Brock et al. (1995) outside tropics -●- COPAS n 10 – median (2002) Arctic Latitudes -●- COPAS n 10 inside polar vortex (2003) -○- COPAS n 10 outside polar vortex (2003) Tropics ― Brock et al. (1995) inside tropics -●- COPAS n 10 Brasil (2005) -●- COPAS n 10 Australia (2005) Striking increase inside 2003 arctic vortex above 400 K

EXAMPLE: Arctic data 2003 high fraction of non-volatile particles inside Arctic vortex (~70 %) Curtius et al., ACP, 2005 EUPLEX 2003 Ratio of non-volatile particle number to total particle number > 10nm, < 1 µm => subsidence of meteoritic material from mesosphere

Mid latitudes ― Brock et al. (1995) outside tropics -●- COPAS n 10 – median (2002) Arctic Latitudes -●- COPAS n 10 inside polar vortex (2003) -○- COPAS n 10 outside polar vortex (2003) Tropics ― Brock et al. (1995) inside tropics -●- COPAS n 10 Brasil (2005) -●- COPAS n 10 Australia (2005) Striking increase inside 2003 arctic vortex above 400 K Explained by IMPORT of meteoric dust from the mesosphere through analysis of non-volatility

TROPICAL BRASIL Non-volatile particles constant at 20-30% in LS More variable, but typically ~10% in TTL and below. Ratio of non-volatile particle number to total particle number > 10nm, < 1 µm

AUSTRALIA 2005 Slightly higher level (10%) of non-volatile particles over the continent than above the sea Ratio of non-volatile particle number to total particle number > 10nm, <1 µm continental Australia tropical „oceanic“ Australia

AMMA: Ouaga ratio of non volatile particles to total number * Values above 360K are at 50%. * Tropical Brazil was 20%. * Tropical Australia 60% but higher up

● n 10 non-volatile ● n 10 total ● n 14 ● n 6 -●- median n 10 AMMA summary: COPAS-data vs altitude particle sizes > 6 nm  1 µm Ouagadougou local flights „Tropospheric variability region“ „Sulfuric acid region“ „Region of high non volatility“ Particle number concentration [cm³] Potential Temperature [K]

(5) Results from specific cases: Biomass burning particles

High CO for biomass burning is correlated with high ultrafine particle Number densities

AMMA flight August 8, 2006 High CO for biomass burning is correlated with high non-volatile ultrafine particle component Theta: Blue 370 K Grey 385 K Yellow 400 K Red 430 K

Biomass burning: Vertical profiles over Accra, August 13, 2006 Difference between n6 and n14 is zero. Thus: no new particle formation in bmb plume above Accra

Direct evidence for homogeneous nucleation in the tropics ● n 6 ● n 15 – altitude Flight altitude in km Non volatile component f ≈ 30% at 13 km altitude Homogeneous Nucleation Particle number density in cm -3 Only ultrafine particles 6 nm  size  14 nm UTC flight time [hours] TROCCINOX, BRAZIL,

Biomass burning: Vertical profiles over Accra, August 4, 2006

Large latitudinal data sets on non-volcanic background ultrafine particles within 2005 through TROCCINOX, SCOUT-O3, AMMA mid-lat. transfer, survey, test flights. For AMMA unexpected increase above 420 K => No explanation sofar. Non-volatility vs. total aerosol number ratios between 20% and 80%, maximum near 400 K => No explanation for this profile sofar. Above ≈ 400 K ultrafine particle numbers constant since 1999 at mid-latitudes Summary

Thanks for your interest.

Heater efficiency of COPAS I at 250°C with pure H 2 O- H 2 SO 4 - particles Boiling point of H 2 O- H 2 SO 4 particles under pressure conditions at 10 – 20 km: ~ 150°C (Rosen, 1971) ● not heated channel ● heated channel at 250°C ○ 300 hPa ∆ 150 hPa ◊ 70 hPa particle diameter in nm particle number concentration in cm -3 (log) particle number density in cm -3 (linear) H 2 SO 4 /H 2 O 150nm particles with 0.5% by volume nonvolatile component will be detected as „non-volatile“.

Hector Cb-cloud flights vs. continental Australia flight ● Hector flight, ● Hector flight, A ● Hector flight, B ● ENVISAT flight, SCOUT-O3 Australia 2005

Red : Darwin Dec Green: Aracatuba, Brazil Feb 2005 Black: mid-lat blue: arctic COPAS n > 10 nm

Import of ultrafine nuclei from high altitudes inside polar vortex Particle number mixing ratio in [ # / mg ] N 2 O mixing ratio in [ ppbv ] EXAMPLE: Arctic data 2003 Correlation of ultrafine particles with long lived tracer N 2 O Curtius et al., ACP, 2005

● n 10 non-volatile ● n 10 total -○- median n 10 Verona Marrakech Are data ok ? Mid-latitude parts of AMMA transfer consistent with other profiles.