envisat validation at tropics j. p.pommereau, a. garnier, f. goutail, f. borchi service d...
TRANSCRIPT
ENVISAT VALIDATION AT TROPICS
J. P.POMMEREAU, A. GARNIER, F. GOUTAIL, F. BORCHIService d ’Aéronomie CNRS, Verrières le Buisson, France A. HERTZOG and F. VIALLaboratoire de Météorologie Dynamique, Palaiseau, France
N. R. P. HARRIS, J. PYLE, R. L. JONES, A. ROBINSON, G. HANSFORDDept of Chemistry, University of Cambridge
A. BUIVANInstituto de Pesquisas MeteorologicasBauru, SP, Brazil
G. LETRENNECNES Toulouse, France
ESABC PARIS 8 Nov
2002
OUTLINE
SAOZ short and long duration balloon flights at the tropics : example of past results
Plan for February - Mars 2003
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
IPMet balloon facility at Bauru-SP (Brazil, 22°S)
• IPMet : Institute of Meteorological Research of the State University of Sao Paulo (UNESP)Bauru
Sao Paulo
HIBISCUS
Meteorological supportWeather radarRadiosondes stationBalloon launch facilityAirport
Stratospheric Regular SoundingNovember 1997
302010010
6 mol.cm
-3
BrO
642010
12 mol.cm
-3
Ozone
30
25
20
15
10
5
0-80 -40 0
(°C)
Temperature
420
109 mol.cm
-3
NO2
SAOZ / SAOZ-BrO flight
February 2001 : SAOZ-MIR test flight
Launched from Bauru (Brazil), Feb 13, 2001
34 days flight, 2 circum-navigation
Validation of measurements at Reunion Island (lidar, sondes)
Recovered in Argentina
Bauru Reunion
Is.Salta
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
Ozone variability
40
35
30
25
20
15
10
5
0543210
Number Density 1012 mol / cm3
O3
SunriseSunsetMean
40
30
20
10
0543210
Ozone (x1012
mol/cm3)
Ozonesondes La Reunion Feb - 300 mLidar La Reunion 23 FebMIR Indian Ocean: Individual profiles Average
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)
Nitrogen Dioxide
40
35
30
25
20
15
10
5
03210
Number density 109 mol / cm3
NO2
Sunrise Sunset
1.00.50.0-0.5
(SS-SR)/SS
NO2 Diurnal Change
• Secondary maximum at 22-24 km
• Highly variable in both UT and LS
• Minimum concentration and diurnal variation at Tropopause
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
Example of Satellite Validation
MIR and HALOE variability along latitude circle
24
22
20
18
16
14
12
10100806040200
Ozone variability (std dev %)
MIR
MIR
HALOE
MIR without transport
OZONE24
22
20
18
16
14
12
10806040200
NO2 variability at sunrise (std dev %)
Haloe
MIR
MIR Horiz.Transport removed
NO2
Tropopause Tropopause
HALOE O3 and NO2 perturbed by clouds below 22 kmMeasurements not reliable below tropopause
35
30
25
20
15
10
5
06420
Extinction at 550nm(10-3 km-1)
Opaque clouds(Ci, sub-vis Ci)
Sunrise, Sunset
Tropopause Haze
Rayleigh Extinction
Clouds
Observations
Optical Extinction at 550 nm
32
28
24
20
16
10
2
3
4
56
100
AfricaAustralia AustraliaS. America
300
250
200
150
100
50706560555045
Global IR Radiometer
-80
-60
-40
-20
Day 2001
Global IR
Radiometer
300
250
200
150
100
50150 100 50 0 -50 -100 -150
LongitudeS. America Africa Australia
20
15
10
5
0
Tropopause Height
Cirrus and sub-visual cirrus
Higher and thicker above continental areas
Permanent ultra-thin tropopause Haze
35
30
25
20
15
10
5
0210
Mie Extinct 550 nm(10-3 km-1)
-100 -80 -60 -40Temperature(°C)
Tropopause Haze
Sunrise, Sunset
- Ubiquitous at T<200K- 1 part./Cc (r=1µm)
• Size distribution ?
• Formation ?
• Photochemical impact ?
Electrical discharges in the stratosphere
• Frequency over high convective area ?
• Impact on stratospheric chemistry ?
Electrical impact of payloads and balloon around 20-22 km
60 km
20 km
Blue Jet at AreciboPasko et al., Nature, March 02
LIS Flashes DJF
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