Total ozone reduction in the Arctic since 1994 from SAOZ UV-visible Spectrometers F. Goutail, Service d'A

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ENVISAT VALIDATION AT TROPICS
J. P.POMMEREAU, A. GARNIER, F. GOUTAIL, F.
BORCHI Service d Aéronomie CNRS, Verrières le
Buisson, France A. HERTZOG and F.
VIAL Laboratoire de Météorologie Dynamique,
Palaiseau, France N. R. P. HARRIS, J. PYLE, R.
L. JONES, A. ROBINSON, G. HANSFORD Dept of
Chemistry, University of Cambridge A.
BUIVAN Instituto de Pesquisas Meteorologicas Bauru
, SP, Brazil G. LETRENNE CNES Toulouse, France
ESABC PARIS 8 Nov 2002
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OUTLINE
SAOZ short and long duration balloon flights at
the tropics example of past results Plan for
February - Mars 2003
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PAST EXPERIENCE IN BRAZIL

• Nov 1997 EC Stratospheric Regular Soundings
• Four short duration 10 ZL flights
• SAOZ, SAOZ-BRO, DESCARTES, LABS, OPC
• Nov 2000 and February 2001
• CNES technical MIR flights two ZL

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IPMet balloon facility at Bauru-SP (Brazil, 22S)
HIBISCUS

• IPMet Institute of Meteorological Research of
  the State University of Sao Paulo (UNESP)

Bauru
Sao Paulo
Meteorological support Weather radar Radiosondes
station Balloon launch facility Airport
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Stratospheric Regular SoundingNovember 1997
SAOZ / SAOZ-BrO flight
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February 2001 SAOZ-MIR test flight
Bauru
Reunion Is.
Salta
Launched from Bauru (Brazil), Feb 13, 2001 34
days flight, 2 circum-navigation Validation of
measurements at Reunion Island (lidar,
sondes) Recovered in Argentina
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SAOZ-MIR test flight
Instrumentation (60 kg total) 3 independent
payloads - SAMBA GPS, T, P, IR radiometer,
control and safety - SAOZ Solar occultation
Uv-Visible spectrometer O3, NO2, O2, O4, H2O,
atmospheric extinction - RUMBA GPS, T, high
temporal resolution Pressure
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Ozone variability
Overpass over Reunion Island SAOZ-MIR, lidar and
sondes

• Longitudinal variability
• 3 in LS above 20 km (little influence of
  horizontal transport)
• 30 in UT strong horizontal exchange (highly pv
  correlated)

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Nitrogen Dioxide

• Requires
• Local source of NOx Electric discharges?
  Precipitation of charged particles in Atlantic
  anomaly?
• NOx gas phase chemistry different from currently
  known
• Heterogneous NOx/NOy reactions at tropopause

• Secondary maximum at 22-24 km
• Highly variable in both UT and LS
• Minimum concentration and diurnal variation at
  Tropopause

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Example of Satellite Validation MIR and HALOE
variability along latitude circle
Tropopause
Tropopause
HALOE O3 and NO2 perturbed by clouds below 22
km Measurements not reliable below tropopause
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Clouds Observations
Global IR Radiometer
Optical Extinction at 550 nm
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Cirrus and sub-visual cirrus
Higher and thicker above continental areas
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Permanent ultra-thin tropopause Haze
- Ubiquitous at Tlt200K - 1 part./Cc (r1µm)

• Size distribution ?
• Formation ?
• Photochemical impact ?

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Electrical discharges in the stratosphere
Electrical impact of payloads and balloon around
20-22 km
Blue Jet at Arecibo Pasko et al., Nature, March 02
60 km
20 km
LIS Flashes DJF

• Frequency over high convective area ?
• Impact on stratospheric chemistry ?

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ENVISAT VALIDATION CAMPAIGN FEBRUARY 2003
TWO 10 ZL BALLOONS (ONE SUNSET, ONE
SUNRISE) SAOZ (O3, NO2, H2O, clouds), SAOZ-UV
(BrO, OClO ? CH2O?), DIRAC GC (N2O, CFC),
DESCARTES (SLS, O3 SSS, H2O SAW, Micro-Lidar
TWO MIR (2 months autonomy) Met, Global IR
radiometer, lightning detector. 1st regular
SAOZ (O3, NO2, trop. H2O, extinction at 550 nm)
2nd SAOZ H2O (O3, NO2, strat H2O, extinction at
1 µm) RADIOSONDES RS-90, O3 SSS, O3 ECC, H2O
SAW, H2O H-Humicap