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3. Februar 2011 SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011 Slide 1
Herman G.J. Smit Institute of Chemistry and Dynamics of the Geosphere: Troposphere (ICG-2),
Research Centre Juelich (FZJ) , D-52425 Juelich, Germany (e-mail: [email protected])
SPARC/IOC/WMO-IGACO Workshop on
Past Changes in the Vertical Distribution of Ozone
Geneva, January 25-27 2011
Overview of the performance of ozone sondesand their uncertainties
3. Februar 2011 Slide 2SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Performance ECC-Ozone
Sounding: Intercomparison
0
5
10
15
20
25
30
35
Alt
itu
de
[
km
]
180 200 220 240 260 280 300
Temperature [Kelvin]
0 5 10 15 20
Ozone , Pressure [ mPa ]
Ozone Pressure
Temperature
Grey Line = ECC-Sonde Kasshidoo
ECC-Ozone sensor converts sampled ozone flow into electrical current:
�In aqueous KI-solution Ozone is converted into Iodine molecules
�In electrochemical cell Iodine is converted at Pt-Cathode into Iodide-ions
3. Februar 2011 Slide 3SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
JOSIE-1996: Juelich Ozone Sonde Intercomparison Experiment
-30 -20 -10 0 10 20 30Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-A-MOHp [1]BM-orig.
File : JSRMD1C.GRF
-30 -20 -10 0 10 20 30Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-B-CMDL [2]ECC/ENSCI-1Z
File : JSRMD2C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-D-IMD [4]Indian
File : JSRMD4C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-E-ASP [5]BM-Hybrid
File : JSRMD5C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-G-CNRS [7]ECC/ SPC-5A
File : JSRMD7C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-H-JMA [7]KC79
File : JSRMD8C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-F-AES [6]ECC/SPC-5A &ECC/ENSCI-1Z
File : JSRMD6C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-C-FZJ [3]ECC/SPC-6A
File : JSRMD3C.GRF
INDIANECCBrewer-Mast
ECC
ECC
ECC JapaneseKC79
BM-Hybrid
3. Februar 2011 Slide 4SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Conversion Efficiency ECC-Sonde: Influence of Sensing Solutions (KI & Buffer)
Johnson, et al, J. Geophys. Res., 2002
Stoichiometry (O3 + KI) Reactionyielding I2 at 1% KI, full Buffer:
At launch stoichiometry is unity
During flight evaporation of H2O
Increase concentrations of KI & Buffer
Increase of stoichiometry
Majorly due to increase of buffer
Ozone (mPa)
3. Februar 2011 Slide 5SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Manufacturer Model Type Years Manufactured.
Science Pump SPC-6A 1995- present
EN-SCI ENSCI-Z 1997 –present
PH-Buffer
Sensing Solution Type (SST)
KI
[g/L] NaH2PO4.H2O
[g/L]
Na2HPO4.12H2O
[g/L]
KBr
[g/L]
SST1.0: 1.0% KI & full buffer (a) 10 1.250 5.0 25
SST0.5: 0.5% KI & half buffer (b) 5 0.625 2.5 12.5
SST2.0: 2.0% KI & no buffer (c) 20 0 0 0
Controversy ECC-sondes since Mid 1990‘s:Two Manufacturers and 3 Different Sensing Solution Types
3. Februar 2011 Slide 6SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
JOSIEJülich
Ozone SondeIntercomparison
Experiment
ASOPOSAssessment forStandard
OperatingProcedures forOzone
Sondes
BESOSBalloon
Experiment onStandards forOzone
Sondes
Since 1996 April 2004, atLaramie, USA
JOSIEJülich
Ozone SondeIntercomparison
Experiment
ASOPOSAssessment forStandard
OperatingProcedures forOzone
Sondes
BESOSBalloon
Experiment onStandards forOzone
Sondes
Since 1996 April 2004, atLaramie, USA
Sources: JOSIE [Smit et al., J.Geophys.Res., 2007] BESOS [Deshler et al., J.Geophys.Res., 2008]
WCCOSWorld
Calibration
Centre for
Ozone
Sondes
At Juelich,
Germany
JOSIE – ASOPOS - BESOS
3. Februar 2011 Slide 7SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Sondes versus OPM : BESOS versus JOSIE
1. Systematic difference of 3-6%
2. Compared to sondes: OPM in
BESOS about 3-6 % lower than
in JOSIE.
3. Limited performance OPM during
BESOS
4. Behaviour of sondes in
stratosphere very consistent
during JOSIE 1996, 1998, 2000
and BESOS
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST0.5 (N=8sondes)
BESOS-2004: SST0.5 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
SPC-6A
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40A
ltit
ude [k
m]
JOSIE-2000: SST0.5 (N=5sondes)
BESOS-2004: SST0.5 (N=3sondes)
SPC-6A
SST1.0 SST0.5
SST1.0 SST0.5
A B
C D
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST0.5 (N=8sondes)
BESOS-2004: SST0.5 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
SPC-6A
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40A
ltit
ude [k
m]
JOSIE-2000: SST0.5 (N=5sondes)
BESOS-2004: SST0.5 (N=3sondes)
SPC-6A
SST1.0 SST0.5
SST1.0 SST0.5
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST0.5 (N=8sondes)
BESOS-2004: SST0.5 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
SPC-6A
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40A
ltit
ude [k
m]
JOSIE-2000: SST0.5 (N=5sondes)
BESOS-2004: SST0.5 (N=3sondes)
SPC-6A
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST0.5 (N=8sondes)
BESOS-2004: SST0.5 (N=3sondes)
ENSCI-Z
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude [k
m]
JOSIE-2000: SST1.0 (N=8sondes)
BESOS-2004: SST1.0 (N=3sondes)
SPC-6A
-15 -10 -5 0 5 10 15 20 25Relative Differences [%]
(Sonde-OPM)/OPM
0
5
10
15
20
25
30
35
40A
ltit
ude [k
m]
JOSIE-2000: SST0.5 (N=5sondes)
BESOS-2004: SST0.5 (N=3sondes)
SPC-6A
SST1.0 SST0.5
SST1.0 SST0.5
A B
C D
SPC-6ASST1.0
SPC-6ASST0.5
ENSCI-ZSST1.0
ENSCI-ZSST0.5
JOSIE JOSIE
JOSIE JOSIE
BESOSBESOS
BESOS BESOS
3. Februar 2011 Slide 8SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Sondes versus Sondes : BESOS versus JOSIE
-10 -5 0 5 10 15 20Relative Differences [%]
(ENSCI-Z minus SPC-6A)/OPM
0
5
10
15
20
25
30
35
40A
ltit
ude
[km
]
ENSCIZ: SST1.0 & SPC6A: SST1.0
ENSCIZ: SST0.5 & SPC6A: SST0.5
ENSCIZ: SST1.0 & SPC6A: SST0.5
ENSCIZ: SST0.5 & SPC6A: SST1.0
-10 -5 0 5 10 15 20Relative Differences [%]
(ENSCI-Z minus SPC-6A)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude
[km
]
ENSCIZ: SST1.0 & SPC6A: SST1.0
ENSCIZ: SST0.5 & SPC6A: SST0.5
ENSCIZ: SST1.0 & SPC6A: SST0.5
ENSCIZ: SST0.5 & SPC6A: SST1.0
JOSIE2000
BESOS
2004
A B
-10 -5 0 5 10 15 20Relative Differences [%]
(ENSCI-Z minus SPC-6A)/OPM
0
5
10
15
20
25
30
35
40A
ltit
ude
[km
]
ENSCIZ: SST1.0 & SPC6A: SST1.0
ENSCIZ: SST0.5 & SPC6A: SST0.5
ENSCIZ: SST1.0 & SPC6A: SST0.5
ENSCIZ: SST0.5 & SPC6A: SST1.0
-10 -5 0 5 10 15 20Relative Differences [%]
(ENSCI-Z minus SPC-6A)/OPM
0
5
10
15
20
25
30
35
40
Alt
itude
[km
]
ENSCIZ: SST1.0 & SPC6A: SST1.0
ENSCIZ: SST0.5 & SPC6A: SST0.5
ENSCIZ: SST1.0 & SPC6A: SST0.5
ENSCIZ: SST0.5 & SPC6A: SST1.0
JOSIE2000
BESOS
2004
A B
JOSIE2000
BESOS2004
3. Februar 2011 Slide 9SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
For each Sensing Solution Type
(SST1.0 , SST0.5, and SST2.0) :� ENSCI 5-10 % higher than SPC� Precision about 3-6 %
Each sonde type (ENSCI or SPC):
�SST1.0 ≈ 5% larger than SST0.5�SST0.5 ≈ 5% larger than SST2.0�SST1 ≈ 10% larger than SST2.0
JOSIE 2000 & BESOS 2004: Comparison SPC-6A&ENSCI-Z @ Different Sensing Solutions
SST1.0 (1.0%KI,Full Buffer), SST0.5 (0.5%KI,Half Buffer), SST2.0 (2.0%KI, No Buffer)
[Data processed after Komhyr 1986, IB0 (PO2), No Total O3 Normalization]
3. Februar 2011 Slide 10SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
1.) Small changes of
a. ozone sonde instrument (e.g. manufacturers) b. operating procedures (e.g. sensing solutions)
can have large impact on sonde data quality
2.) Non-uniformity in data processing
3.) Establishment of Standard of Operating Procedures
(SOP) for ozone sondes by ASOPOS recomendations
4.) After standardization and homogenization
improvement of precision and accuracyby about factor 2 can be expected
ECC-Ozone Sonde Performance:What we learned from JOSIE and BESOS
3. Februar 2011 Slide 11SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Established with following plan:
1) Construct/derive empirical transfer functions from existing data:
Relative Diffference PO3 (Z)
Absolute Difference PO3 (Z)
Absolute Difference PO3 (PO3)
2) Evaluate transfer functions: testing a set of homogenized O3S data on consistency (e.g. use MATCH, satellites, MOZAIC).
3) Recommendations on the methodology to homogenize data
4) Review by independent panel of scientists (O3S data users)
5) Approval of recommendations by WMO/GAW-O3-SAG and NDACC-SSC
Task force group established as WMO/GAW-IGACO activity in
collaboration with the NDACC and SHADOZ ozone sounding networks.
Task force group:
Transfer functions to homogenize ozone sonde records
3. Februar 2011 Slide 12SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
JOSIE-1996: Overview Comparison Ozone Sondes
-30 -20 -10 0 10 20 30Relative Deviation [ % ]
0
5
10
15
20
25
30
35A
ltitude
[ km
]
Fig.-A-MOHp [1]BM-orig.
File : JSRMD1C.GRF
-30 -20 -10 0 10 20 30Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-B-CMDL [2]ECC/ENSCI-1Z
File : JSRMD2C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-D-IMD [4]Indian
File : JSRMD4C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-E-ASP [5]BM-Hybrid
File : JSRMD5C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-G-CNRS [7]ECC/ SPC-5A
File : JSRMD7C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-H-JMA [7]KC79
File : JSRMD8C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-F-AES [6]ECC/SPC-5A &ECC/ENSCI-1Z
File : JSRMD6C.GRF
-30 -20 -10 0 10 20 30
Relative Deviation [ % ]
0
5
10
15
20
25
30
35
Altitude
[ km
]
Fig.-C-FZJ [3]ECC/SPC-6A
File : JSRMD3C.GRF
INDIANECCBrewer-Mast
ECC
ECC
ECC JapaneseKC79
BM-Hybrid
3. Februar 2011 Slide 13SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
A B
JOSIE-BESOS: Improvement KC96-Ozone Sonde
Before After
3. Februar 2011 Slide 14SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Electrochemical Ozone Sonde: Introduction
In an electrochemical cell:
A small pump forces ambient air through
a KI-solution
Ozone is converted into iodine by the reaction:
At a Platinium cathode the Iodine is converted
to Iodide:
In external electrical circuit a current is generated
directly related to the uptake rate of ozone in the
sensing solution
KOH2OIOHOKI2 2223 ++++++++→→→→++++++++
PtI2e2I2 →→→→++++ −−−−PtI2e2I2 →→→→++++ I2e2I2 →→→→++++ −−−−
(((( ))))BMP
PC3O II
T04307.0P −−−−⋅⋅⋅⋅
ΦΦΦΦ⋅⋅⋅⋅ηηηη⋅⋅⋅⋅====
Pump Flow [cm3/s]
Ozone Pressure[mPa]
Conversion Efficiency
BackgroundCurrent [µA]
MeasuredCurrent [µA]
Pump Temperature [K]
3. Februar 2011 Slide 15SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
0.0 5.0 10.0 15.0 20.0Ozone Partial Pressure [mPa]
0
5
10
15
20
25
30
35
Altitude [k
m]
0 2.5 5 7.5 10Relative Uncertainty to Ozone [%]
0.0 5.0 10.0 15.0 20.0Ozone Partial Pressure [mPa]
0
5
10
15
20
25
30
35
Altitude [k
m]
0 5 10 15 20Relative Uncertainty to Ozone [%]
A: Mid Latitude B: Tropics
Pressure O3 (PO3)
Rel.Unc.PO3
Rel.Unc.IBack & IM
Rel.Unc.Conversion O3 to I2
Rel.Unc.Pump Flowrate
Rel.Unc.Pump Temperature
0.0 5.0 10.0 15.0 20.0Ozone Partial Pressure [mPa]
0
5
10
15
20
25
30
35
Altitude [k
m]
0 2.5 5 7.5 10Relative Uncertainty to Ozone [%]
0.0 5.0 10.0 15.0 20.0Ozone Partial Pressure [mPa]
0
5
10
15
20
25
30
35
Altitude [k
m]
0 5 10 15 20Relative Uncertainty to Ozone [%]
A: Mid Latitude B: Tropics
0.0 5.0 10.0 15.0 20.0Ozone Partial Pressure [mPa]
0
5
10
15
20
25
30
35
Altitude [k
m]
0 2.5 5 7.5 10Relative Uncertainty to Ozone [%]
0.0 5.0 10.0 15.0 20.0Ozone Partial Pressure [mPa]
0
5
10
15
20
25
30
35
Altitude [k
m]
0 5 10 15 20Relative Uncertainty to Ozone [%]
A: Mid Latitude B: Tropics
Pressure O3 (PO3)
Rel.Unc.PO3
Rel.Unc.IBack & IM
Rel.Unc.Conversion O3 to I2
Rel.Unc.Pump Flowrate
Rel.Unc.Pump Temperature
Pressure O3 (PO3)
Rel.Unc.PO3
Rel.Unc.IBack & IM
Rel.Unc.Conversion O3 to I2
Rel.Unc.Pump Flowrate
Rel.Unc.Pump Temperature
Pressure O3 (PO3)
Rel.Unc.PO3
Rel.Unc.IBack & IM
Rel.Unc.Conversion O3 to I2
Rel.Unc.Pump Flowrate
Rel.Unc.Pump Temperature
Instrumental Uncertainties of ECC-Ozone Sonde
3. Februar 2011 Slide 16SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Two rate constants:
• 1/10th buffer: τ = 19 s, τ’ = 24 min
• full buffer : τ = 19.7 s, τ’ = 28 min
(similar to Davies et al., QOS 2000)
���� Can be used for time lag corrections!
ECC-Sonde: Downward Step Response[Source: Voemel & Diaz, AMT 2010]
'
00
'
00)( ττ
tttt
eIeItI
−−
−−
+=
3. Februar 2011 Slide 17SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
ECC-Background Current Correction @JOSIE 1998
BG1 = Before O3 Exposure (IB0) , No F(PO2)BG2 = Before O3 Exposure (IB0) , F(PO2)
BG3 = After O3 Exposure (IB1) , No F(PO2)BG4 = After O3 Exposure (IB1) , F(PO2 )
ENSCI-Z
BG1 BG2
BG3 BG4
SPC-6A
BG1 BG2
BG3 BG4
No F(PO2) = Constant F(PO2) = O2-pres. dependent
3. Februar 2011 Slide 18SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
0.52±±±±0.100.10±±±±0.0528.6±±±±3.227.7±±±±2.9AverageENSCI-Z
0.52±±±±0.150.16±±±±0.0721.5±±±±2.924.0±±±±1.7AverageSPC-6A
StratosphereTroposphereStratosphereTroposphere
Offset (mPa)
(@t=5min)
Response Time (s)Sonde
Nr.Sonde Type
JOSIE 1998: Downward Response Tests ECC-Sondes (13xSPC6A and 13xENSCI-Z-)
3. Februar 2011 Slide 19SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Icell - ITEI = α·Icell + β
Offset parameter β:
Modified background
Slope parameter α:
Correction for stoichiometry
IO3 = (1-α) • ICell – β
full buffer :α = 0.090, β = 0.014µA
1/10th buffer : α = 0.031, β = 0.007µA
0.5% : α = 0.024, β = 0.009µA
ECC-Sonde: Background measurement with O3[Source: Voemel & Diaz, AMT 2010]
3. Februar 2011 Slide 20SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
0
10
20
30
40
Alt
itude
[km
]
1000
100
10
Pre
ssure
[h
Pa]
270 280 290 300 310Temperature [K]
0 1 2 3 4 Rel. Deviation (TInt-TExt)/TInt [x100%]
Pump Temp. Extern
Pump Temp. Intern
Rel.Deviation (TINt-TExt)/TInt
TIntern
TExtern
RelativeDeviation
Pump Temperature:Internally or Externally Measured
Internal pump temperature:
inside the Teflon block of the pump
External pump temperature:
outside the Teflon block of the pump
corresponds to box temperature
3. Februar 2011 Slide 21SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
Ozone Sonde:Total Ozone Column and Normalization Factor (NF)
TOC = TOS + ROC
TOC = Total Ozone Column between surface and top of atmosphere (TOA)
TOS = Total Ozone Column between surface and burst point (PB, ZB)
ROC = Residual Ozone Clumn above burst point (PB, ZB)
TOS : Dependent on Accuracy of Z, P
ROC : Dependent on Accuracy of ZB, PB
CMR-Method OR SBUV-Method
TO3 = Total Ozone Column measured by Dobson or Brewer Or Satellite
NF = TO3 / TOC
3. Februar 2011 Slide 22SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
1.00 1.10 1.20 1.30
Pump Correction Factor
1000
100
10
Pre
ssu
re
[hP
a]
Komhyr 1986
Komhyr 1995
CMDL 1996
CMDL 2000
WFF 2000
0
10
20
30
40A
ltit
ud
e [
km
]
Pump Flowrate Correction at Low Pressures
JOSIE :[ CMDL(NOAA) and
WFF(NASA) are
averages from about 6 individually calibrated
pumps ]
3. Februar 2011 Slide 23SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
1) Review different laboratory methods by “experts”
2) Intercomparison of existing methods by ring-experiment
of a set of SPC6A and ENSCI pumps by testing laboratories (NOAA, UWY, WFF, KMI & JMA) [Blind &
Referee].
3) Evaluation
4) Implications
5) Recommendations
6) Approval by WMO/SAG-O3 to include as
recommendation into the SOP’s
Task force group “O3S-Pump Flow Correction”
Time schedule: 2010-2012IGACO-O3 activity
3. Februar 2011 Slide 24SPARC/IOC/WMO-IGACO-Meeting, WMO, Geneva, 25-27 Jan.2011
In how far O3-Sondes usable for trend analysis?
Altitude:ECC : 0- 30 km (uncert. 5-10%)
BM: 0- 25 km (uncert. 10%) ; KC79/96: 0-25 km (uncert.10%)
Long term stability:
Only for limited number of stations after selection on „objective“criteria to be defined by panel of experts.
Level of confidence:
Limited with respect to poor coverage in space and time
Yes, but depends on stations, sonde type , and length of record
Internal consistency of single station
External consistency: Intercomparison excercises like JOSIE, BESOS and other field activities (e.g. dual-soundings)