1. LSCE Laboratoire des Sciences du Climat et de l'Environnement; Gif-Sur-Yvette Cedex; France
2. LMD; Paris France
3. Alfred Wegener Institute Helmholtz-Center for Polar and Marine Research Bremerhaven; Bremerhaven Germany
4. ETH Zurich; Zürich Switzerland
5. Geophysical Institute; University of Bergen; Bergen Norway
6. Spectroscopie de l'Atmosphère, Chimie Quantique et Photophysique; Université Libre de Bruxelles; Brussels Belgium
7. Department of Geography; University of Liège; Liège Belgium
8. NASA Jet Propulsion Laboratory; Pasadena California USA
9. Centre for Ice and Climate, Niels Bohr Institute; University of Copenhagen; Copenhagen Denmark
10. Sorbonne Universités; UPMC University of Paris 06; Université Versailles St-Quentin; CNRS/INSU, LATMOS-IPSL; Paris France
11. Institute of Earth Sciences; University of Iceland; Reykjavik Iceland