Réseau NDSC-FranceRéseau NDSC-FranceNDACCNDACC

P. Keckhut Coordinateur du NDACC-France

LATMOS / IPSL

Objectifs ScientifiquesObjectifs Scientifiques

Etude de la variabilité et détection des changements d’origine anthropique

Fournir une base de référence notamment pour la validation des expériences spatiales

Permettre des études de processus.

Détection des Changements de la StratosphèreNetwork for the Detection of Stratospheric ChangesFirst discussions 1986, implementation in 1991

InstrumentsInstruments LIDAR profiles

– Raman lidar measuring water vapor– Differential Absorption Lidar (DIAL) measuring O3– Backscatter lidars measuring aerosol– Raman and Rayleigh lidars measuring temperature

MICROWAVE RADIOMETERS– Ozone, water vapor, and ClO profiles

UV/VISIBLE SPECTROMETERS – Column abundance of ozone, NO2, and, at some latitudes,

OClO and BrO FTIR SPECTROMETERS

– Column abundances of a broad range of species including ozone, HCl, NO, NO2, ClONO2, and HNO3

DOBSON/BREWER SONDES– Ozone total column

SONDES– Ozone profiles and Aerosol profile

UV radiation at the ground

Validation des instruments Validation des instruments du réseaudu réseau

Intercomparaisons– Déplacement des instruments sur un

même site.

– Comparaisons successives à partir d’un instrument mobile.

– Utilisation d’expériences spatiales comme transfert géographique.

Tests d’algorithme– Signaux artificiels

– Echanges de données brutes

OZONE

TEMPERATURE

IntercomparaisonSondes ballon

Contribution FrançaiseContribution Française Constitué de 5 stations primaires et de

nombreues stations secondaires Contribution Française: ALOMAR

(69°N), Station Alpine (44°N), La Réunion (21°S), Dumont D’Urville (67°S), Réseau SAOZ

Réseau NDSC depuis 1991. SO INSU depuis 1994.

Données publiques après 2 ans bases de données hébergées à la NOAA.

Exercises d’intercomparaisons. Financements : INSU, IPEV, MATE,

ADEME, CNES, Collectivités locales.

NDACC GoalsNDACC Goals

Detecting trends in overall atmospheric composition and understanding their impacts on the stratosphere and troposphere,

Studying atmospheric composition variability at interannual and longer timescales,

Establishing links and feedbacks between climate change and atmospheric composition,

Calibrating and validating space-based measurements of the atmosphere,

Supporting process-focused scientific field campaigns, and Testing and improving theoretical models of the atmosphere.

NDACC OrganizationNDACC Organization The NDACC Steering Committee consists of two co-chairs, pairs of

PIs representing each of the Working Groups, Independent Scientists who are appointed to act as peer reviewers, and ex-officio members from important NDACC funding agencies.

Science Team Representatives – Dobson & Brewer – FTIR – LIDAR – Microwave – Ozonesondes & Aerosol Sondes – Satellite – Spectral UV – Theory & Analysis– UV/Visible

– Peer and Ex-Officio Representatives

OHP temperature evolution OHP temperature evolution in winter 1996/97in winter 1996/97

Gravity wavesGravity waves

Gravity waves in Doppler wind Gravity waves in Doppler wind

zonal meridionalzonal meridional

Mesospheric inversionsMesospheric inversions

Ozone trendsOzone trends

Multiregression analysis Linear decrease of 5-10%/decade Good agreement between Lidar,

Umcker and SAGE Lack of long data series in the lower

stratosphere Probable discontinuities in

ozonosonde series

Coll. M. Guirlet et S. Godin

Origine of the ozone depletionin the lower stratosphere at mid-latitude ?

Vortex evolution in Vortex evolution in December 1997December 1997

Example of polar filament simulated by the high-resolution transport model MIMOSA (Hauchecorne et al., 2002, Godin et al., 2002)

Study of polar filamentsStudy of polar filaments

Synergie sol-espaceSynergie sol-espace

Valider les expériences spatiales

Assurer la continuité d’expériences spatiales successives et estimer des tendances à l’échelle globale

QuickTime™ et undécompresseur TIFF (non compressé)

sont requis pour visionner cette image.HALOE

GOMOS

NCEP/LIDAR à 1hPa