Category Archives: Uncategorized

Atelier EECLAT 2016 – le bilan

The EECLAT 2016 workshop took place between January 27th and 29th, 2016 in Carcassonne, France. Here is the program. Below is the list of scientific presentations with links to slides.

Thanks to all participants! Also thanks to the Hotel Mercure Carcassonne staff who provided the infrastructure and coffee. Thanks to IPSL admins (including F. Beaud) for their help organizing the trip.

Debriefing of EECLAT 2016 proposal : recommandations and budget

Atelier EECLAT 2015 – le bilan

The EECLAT 2015 workshop took place between January 19th and 21st, 2015 in Ploumanac’h, France. Below is the final programme, with links to the scientific presentations.

Thanks to all participants! Also thanks to the Castel Beau Site hotel staff who provided the infrastructure and coffee. Thanks to IPSL admins (including F. Beaud) for all their help organizing the trip.

Pre-workshop Information


2015-01-21 16.52.29


Lundi 19 Janvier

14h Accueil

14h30 Message d’introduction du Centre de Météorologie Spatiale (CMS)

14h50 Rappels des thèmes scientifiques d’EECLAT et updates WP : T1.1T2.8+T2.9T4.2T4.3T5.2

15h50 Infos générales EECLAT (J. Delanoe) + CALIPSO status et V4 (J. Pelon)

16h30 Break

17h00 Projets en lien avec EECLAT


Mardi 20 Janvier

9h00 Exposés scientifiques

10h30 Break

11h00 Suite des exposés

12h30 Déjeuner

14h45 Suite des exposés

17h00 Break

17h30 Suite des exposés

18h50 Bilan EECLAT 2014-2015 – V. Noel


Mercredi 21 Janvier

9h00 EECLAT 2015-2016 (Notes de Réunion)

10h30 Break

14h00 Visite du CMS

16h00 fin de l’atelier

2015-01-21 14.15.21

EECLAT 2014 workshop – post-mortem

The EECLAT 2014 workshop took place between January 20th and 22nd, 2014 in La Rochelle, France. Below is the final programme, with links to the scientific presentations.

Thanks to all participants! Also thanks to the La Rochelle Mercure hotel staff who provided the infrastructure and coffee. Thanks to LMD admins (S. Sportouch, I. Ricordel, S. Agasse, S. Lekieffre, MD. Coudert, and M. Maherou) for all their help organizing the trip.

2014-01-22 La Rochelle

Peu de touristes à la Rochelle

During the workshop the group decided to reconvene next year around the same dates, probably in Lannion.


Lundi 20 janvier

14h Accueil

14h30 Infos générales EECLAT, J. Delanoe

15h30 Validation CALIPSO et produits nominaux (T0)

16h30 Nuages à l’échelle locale et régionale (T1)

Mardi 21 janvier

9h Nuages à l’échelle locale et régionale, suite (T1)

11h Nuages à l’échelle globale (T2)


14h Outils de transfert radiatif et produits futurs (T5)

16h30 Données pour préparer EarthCare (T6)

17h30 Bilan EECLAT 2013 et propal 2014


Mercredi 22 janvier

9h EECLAT 2015 (discussion ouverte, notes G. Sèze)

2014-01-22 Machine a café


Publications acceptées, June 2013

Hoareau, C., Keckhut, P., Noel, V., Chepfer, H., and Baray, J.-L. 2013: A decadal cirrus clouds climatology from ground-based and spaceborne lidars above south of France (43.9° N–5.7° E), Accepted to Atmos. Chem. Phys. (ACPD reference: vol. 13, 6379-6417, doi:10.5194/acpd-13-6379-2013)

This study provides an analysis of cirrus clouds properties at midlatitude in the southern part of France from ground-based and spaceborne lidars. A climatology of cirrus clouds properties and their evolution over more than 12 yr is presented and compared to other mid-latitude climatological studies. Cirrus clouds occur ~ 37% of the total observation time and remain quasi-constant across seasons with a variation within ~ 5% around the mean occurrence. Similar results are obtained from CALIOP and the ground-based lidar, with a mean difference in occurrence of ~ 5% between both instruments. From the ground-based lidar data, a slight decrease in occurrence of ~ 3% per decade is observed but found statistically insignificant. Based on a clustering analysis of cirrus cloud parameters, three distinct classes have been identified and investigations concerning their origin are discussed. Properties of these different classes are analysed, showing that thin cirrus in the upper troposphere represent ~ 50% of cloud cover detected in summer and fall, decreasing by 15–20% for other seasons.

Ceccaldi M., J. Delanoë, R. J. Hogan , N. Pounder , A. Protat , J. Pelon, 2013: From CloudSat-CALIPSO to Earth-Care : Evolution of the DARDAR cloud classication and its validation using airborne radar-lidar observations. J. Geophys. Res. 10.1002/jgrd.50579

This paper presents the implementation of a new version of the DARDAR (raDAR liDAR) classification derived from CloudSat and CALIPSO data. The resulting target classification called DARDAR v2 is compared to the first version called DARDAR v1. Overall DARDAR v1 reports more cloud or rain pixels than DARDAR v2. In the low troposphere this is because v1 detects too many liquid cloud pixels, and in the higher troposphere this is because v2 is more restrictive in lidar detection than v1. Nevertheless, the spatial distribution of different types of hydrometeors show similar patterns in both classifications. The French airborne RAdar -LIdar (RALI) platform carries a CloudSat/CALIPSO instrument configuration (Lidar at a wavelength of 532 nm and a 95GHz cloud radar), as well as an EarthCare instrument configuration (High Spectral Resolution Lidar at 355 nm and a 95 GHz Doppler cloud radar). It therefore represents an ideal go-between for A-Train and EarthCare. The DARDAR v2 classification algorithm is adapted to RALI data for A-Train overpasses during dedicated airborne field experiments using the lidar at 532 nm and the radar Doppler measurements. The results from the RALI classification are compared with the DARDAR v2 classification to identify where the classification should still be interpreted with caution. Finally the RALI classification algorithm with lidar at 532 nm is adapted to RALI with High Spectral Resolution lidar data at 355 nm in preparation for EarthCare.

Proposition ISS-LIS sélectionnée

E. Defer a annoncé que…

la proposition ISS-LIS a été sélectionnée. Il s’agit de l’installation sur la station spatiale du capteur d’éclairs LIS (Lightning Imaging Sensor) identique (“spare version”) à celui qui est opéré depuis 1997 sur la mission TRMM. Lancement prévu en 2016.

La synergie entre ISS-CATS et ISS-LIS pourra être explorée (si les stratégies d’observation sont compatibles) à partir des résultats obtenus au sein d’EECLAT via le T2.4. Affaire à suivre donc!

Publication acceptée, avril 2013

Level1 measurements, including cross-polarized backscatter, from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar have been used to document the vertical structure of the cloud thermodynamic phase at global scale. We built a cloud phase identification (liquid, ice, undefined) in the GCM-Oriented Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) Cloud Product (GOCCP) and analysed the spatial distribution of liquid and ice clouds in 5 JFM seasons of global scale observations (2007-2011). We developed a cloud phase diagnosis in the Cloud Feedback Model Intercomparison Program Observation Simulator Package (COSP) to evaluate the cloud phase description in the LMDZ5B climate model. The diagnosis in the simulator is fully consistent with the CALIPSO-GOCCP observations to ensure differences between the observations and the “model + simulator” ensemble outputs can be attributed to model biases. We compared the liquid and ice cloud vertical distributions simulated by the model with and without the quantify the impact of the simulator. The model does not produce liquid clouds above 3 km, and produces ice instead of liquid at low- and mid-altitudes in polar regions, as well as along the Inter-Tropical Convergence Zone. The model is unable to replicate the observed co-existence of liquid and ice cloud between 0 and -40 °C. Liquid clouds dominate for T > -21 °C in the observations, T > -12 °C in the model + simulator, and T > -7.5 °C in the model parameterization. Even if the simulator shifts the model cloud phase parameterization to colder temperature because of the lidar instrument peculiarities, the cloud phase transition remains too warm compared to observations.