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Transport and transformation of trace species in
deep convective clouds: results of the ACRIDICON
tracer experiment
Hans Schlager1, Yu Ren1, Robert Baumann1, Michael Lichtenstern1,
Daniel Fütterer1, Helmut Ziereis1, Ramon Campos Braga2
1DLR-Institut of Atmospheric Physics, Oberpfaffenhofen, Germany2INPE-National Institute for Space Research, São José dos Campos, Brazil
Int. ACRIDICON-CHUVA Workshop, Ilha Bela, Feb. 28- March 3, 2016
Objectives of Tracer Experiment
• To study vertical air mass transport
associated with deep convection
using ambient (CO) and
artificial tracer (perfluorocarbons)
• To characterize the type and degree
of pollution in the air masses where
convection occurs
• To quantify redistribution of trace
species and their transformations by
clouds
• to study new particle formation in
convective outflow
• To determine LNOx emissions
Measurements used in this analysis
Species Technique Accuracy /DL Remark Operator
CO Fluorescence 5% / 2 ppb Ambient tracer
Schlager,
PMCH Tube samplingTDS-GC-MS
3% / 1 ppq Artificial tracer
Schlager, Ren
NO CL 5% / 5 ppt LNOx tracer Ziereis
NOy Au-converter + CL
10% / 15 ppt NOy ~ NOx +HNO3 + PAN
Ziereis
CN total CPC 15% / 10 cm-3 Fütterer
CN n-v CPC + thermo-denuder
15% / 10 cm-3 Fütterer
Perfluorocarbon
tracer
Properties:
non-toxic
non-reactive
no interaction with aerosol or cloud particles
very low atmospheric background concentration
(~ 5 ppq)
Measurement technique with very low detection limit
available (1 ppq = 10-15)
http://www.esf.edu/for/lautz/Images/TracerRelease.jpg
(Ren et al. AMT, 2015)
PFCs available
PFC Mm Struktur & Name Siedetemp. Hintergrund
C4F8 200 u
PCB
-6°C ?
C6F12 300 u
o-PDCB p-PDCB PCH PMCP
45°C /
48°C /
60°C
0,3 - 2,7 fmol
/mol
?
4,3 - 8,4 fmol
/mol
C7F14 350 u
PMCH
76°C 3,6 - 7,0 fmol
/mol
C8F16 400 uo-PDCH m-PDCH p-PDCH PECH
(cis/trans Isomere unterscheidbar!)
102°C /
102°C
1,3 - 34 fmol
/mol
?
C9F18 450 u
i-PPCH PTCH
130°C /
128°C
0,7 fmol
/mol
0,17 fmol
/mol
Dichte: 1,5 - 2 kg/l
Straume, A. et al., Perfluorocarbon Background Concentrations in Europe. Atm. Env. 32, 4109-4122 (1998)
sowie persönl. Kommunikation Dietz, R., BNL, 2008
6,6
AC16
Thermo Desorption GC/MS SystemAdsorption tube
sampler
PERTRAS rack
on board HALO
- Preconditioning
- Standards
- Blancs
- Desorption
- control
Desorption of
PFC from tubes
and concentration
on cold finger
Gas chromatograph
(Al2O3-PLOT-S column)Triple-MS
ACRIDICON Tracer Experiment AC16
Overview
-63.0 -62.5 -62.0 -61.5 -61.0 -60.5 -60.0 -59.5 -59.0 -58.5 -58.0
-4.5
-4.0
-3.5
-3.0
-2.5
Latitu
de
Longitude
0
4
8
12
16
20
25
30
10-15
mol/mol
release
(10 UTC)4.5 - 5 km,
background ?
(17 UTC)0.6 & 1.3 km
(15 UTC)
0.9 &
1.8 km
(20 UTC)
12 km
(19 UTC)Out of cloud
Profile (17:30)
Anvil
Transects
(18:00)
Manaus
Cb
15 UTC: TracerSampling BL
9:45-10:50 UTC: Tracerrelease Manaus (9 kg)
from Park Hotel
ACRIDICON Tracer Experiment AC16
17 UTC: Approachthundercloud
18 – 18:40 UTC: Samplinganvil
19 – 19:30 UTC: Sampling Downstream of anvil
ACRIDICON Tracer Experiment AC16
20 UTC: SamplingTracer in BL
ACRIDICON Tracer Experiment AC16
Top row: ECMWF 0.15°x0.15°, 1-hourlyBottom row: GDAS 1°x1°, 3-hourly„R“ = place of PMCH release (9:45 – 10:50)
ECMWF
GDAS
11-13 UTC
13
Top row: ECMWF 0.15°x0.15°, 1-hourlyBottom row: GDAS 1°x1°, 3-hourly„R“ = place of PMCH release (9:45 – 10:50)
ECMWF
GDAS
13-15 UTC
14
14.00 15.00 16.00 17.00 18.00 19.00 20.00 21.00
0
5
10
15
20
25
30
35
40
PM
CH
/ 1
0-1
5 m
ol/m
ol
UTC / hours
0
2
4
6
8
10
12
14
16
Altitu
de /
km
ACRIDICON flight AC16 /25 Sep 2014: PMCH
0
2
4
6
8
10
12
14
0 10 20 30 40
Altitude at
begin
end
of sampling
PMCH / 10-15
mol/mol
AL
titu
de
/ k
m
15
BG samplesBG samples
BG
Measurements of CO in the anvil and downstream
Tracer correlation analysis
CO – PMCH Correlation
CO – PMCH Correlation NOy – PMCH Correlation
PMCH /ppq
CN (n-v) – PMCH Correlation
PMCH /ppq PMCH /ppq
CN (n-v) – PMCH Correlation CN (total) – PMCH Correlation
Conclusions & next steps
• The PFC tracer experiment during AC16 worked!
• First tracer correlations analysis looks promising
• More detailed PMCH background analysis will provide addition
tracer plume data for AC16
• We will extent this kind of analysis to further ACRIDICON flights
using the ambient tracer CO
• We seek collaboration with modellers (3-D cloud resolving model)