Observation of tropospheric δD by IASI over the western Siberia: comparison with a general circulation model

Matthieu Pommier (1) , Jean-Lionel Lacour (2) , C. Risi (3) , Francois-Marie Breon (1, 4) , Cathy Clerbaux (5, 2) , Pierre-François Coheur (2) , K. Gribanov (6) , D. Hurtmans (2) , Jean Jouzel (1, 7) , V. Zakharov (6)

1 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
2 Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique
3 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)
4 SATINV - Modélisation INVerse pour les mesures atmosphériques et SATellitaires
5 TROPO - LATMOS
6 Climate and Environmental Physics Laboratory [Russia]
7 GLACCIOS - Glaces et Continents, Climats et Isotopes Stables

This study presents the joint H₂¹⁶O and HDO retrieval from Infrared Atmospheric Sounding Interferometer (IASI) spectra over the Western Siberia. IASI is an instrument on board the MetOp-A European satellite. The global coverage of the instrument and the good signal-to-noise ratio allow us to provide information on δD over this remote region. We show that IASI measurements may be used to estimate integrated δD between the surface and 3 km altitude or from 1 to 5 km depending on the thermal contrast, with observational errors lower than 4% and 8%, respectively. The retrieved data are compared to simulations from an isotopic GCM, LMDZ-iso over 2011. The satellite measurements reproduce well the seasonal and day-to-day variations for δD, showing for the latter a good correlation with the model (r up to 0.8 with the smoothed data in summer). The IASI-based retrievals also show the seasonal variation of the specific humidity in both altitude ranges.

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Matthieu Pommier, Jean-Lionel Lacour, C. Risi, Francois-Marie Breon, Cathy Clerbaux, et al.. Observation of tropospheric δD by IASI over the western Siberia: comparison with a general circulation model. Atmospheric Measurement Techniques, 2014, 7, pp.1581-1595. ⟨10.5194/amt-7-1581-2014⟩. ⟨hal-00920145⟩