The Evolution of Titan's Mid-Latitude Clouds
Caitlin A. Griffith
(1)
,
Paulo Penteado
(1)
,
Kevin H. Baines
(2)
,
Pierre Drossart
(3, 4, 5)
,
J. Barnes
(1)
,
Giancarlo Bellucci
(6)
,
J. Bibring
(7)
,
R. Brown
(1)
,
B. Buratti
(2)
,
Fabrizio Capaccioni
(8)
,
Priscilla Cerroni
(8)
,
Roger N. Clark
(9)
,
Michel Combes
(3, 4, 5)
,
Angioletta Coradini
(8)
,
Dale P. Cruikshank
(10)
,
Vittorio Formisano
(6)
,
Ralf Jaumann
(11)
,
Yves Langevin
(7)
,
Dennis L. Matson
(2)
,
Thomas B. Mccord
(12)
,
Vito Mennella
(13)
,
Richard P. Nelson
(2)
,
Philip D. Nicholson
(14)
,
Bruno Sicardy
(3, 4, 5)
,
Christophe Sotin
(15)
,
Laurence A. Soderblom
(9)
,
R. Kursinski
(1)
1
LPL -
Lunar and Planetary Laboratory [University of Arizona]
2 JPL - Jet Propulsion Laboratory
3 Observatoire de Paris
4 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
5 Pôle Planétologie du LESIA
6 IFSI - Istituto di Fisica dello Spazio Interplanetario
7 IAS - Institut d'astrophysique spatiale
8 IASF-Roma - Istituto di Astrofisica Spaziale e Fisica Cosmica
9 US Geological Survey, Flagstaff
10 SETI Institute, NASA Ames Research Center, Moffett Field
11 Institute for Planetary Exploration, Deutsches Zentrum for Luft und Raumfahrt
12 Department of Earth and Space Sciences, University of Washington
13 INAF-OAC - INAF-Osservatorio Astronomico di Capodimonte
14 Department of Astronomy, Cornell University
15 LPG - Laboratoire de Planétologie et Géodynamique [UMR 6112]
2 JPL - Jet Propulsion Laboratory
3 Observatoire de Paris
4 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
5 Pôle Planétologie du LESIA
6 IFSI - Istituto di Fisica dello Spazio Interplanetario
7 IAS - Institut d'astrophysique spatiale
8 IASF-Roma - Istituto di Astrofisica Spaziale e Fisica Cosmica
9 US Geological Survey, Flagstaff
10 SETI Institute, NASA Ames Research Center, Moffett Field
11 Institute for Planetary Exploration, Deutsches Zentrum for Luft und Raumfahrt
12 Department of Earth and Space Sciences, University of Washington
13 INAF-OAC - INAF-Osservatorio Astronomico di Capodimonte
14 Department of Astronomy, Cornell University
15 LPG - Laboratoire de Planétologie et Géodynamique [UMR 6112]
Résumé
Spectra from Cassini's Visual and Infrared Mapping Spectrometer reveal that the horizontal structure, height, and optical depth of Titan's clouds are highly dynamic. Vigorous cloud centers are seen to rise from the middle to the upper troposphere within 30 minutes and dissipate within the next hour. Their development indicates that Titan's clouds evolve convectively; dissipate through rain; and, over the next several hours, waft downwind to achieve their great longitude extents. These and other characteristics suggest that temperate clouds originate from circulation-induced convergence, in addition to a forcing at the surface associated with Saturn's tides, geology, and/or surface composition.