PTYS/LPL Faculty

Caitlin Griffith

CURRENT STUDENTS

  • Robert Zellem (PTYS)

FORMER STUDENTS

  • Paulo Penteado, 2009 (PTYS)
  • Johanna K. Teske, 2014 (Astronomy)
Caitlin Griffith
Professor
Planetary atmospheres
Ph.D., 1991, State University of New York, Stony Brook

Kuiper   #424
520-626-3806


Years with LPL:  2002 to present

RESEARCH INTERESTS

Dr. Griffith investigates the chemical, dynamical and thermal structures of planetary atmospheres, using ground-based and spacecraft observations. The data are interpreted with radiative transfer calculations to measure the temperature, composition and dynamical signatures of planetary atmospheres. These results are analyzed with simple chemical, radiative and dynamical models to address questions on atmospheric structure and evolution.

Currently Dr. Griffith is up to her elbows in the analysis of data from the Cassini spacecraft. She is particularly intrigued by Titan, Saturn’s largest moon, which she regards as a deranged version of Earth. On Titan methane acts like water and can exist as a gas in the atmosphere, or as liquid and ice, in rain, snow and lakes. Cassini images of Titan show features near the equator indicative of methane rivers and ancient shorelines reminiscent of Earth, thus suggesting wetter times underneath a cloudless sky. Titan’s methane clouds are found only near the south pole, and, in a narrow band lined up at -40 latitude, like a string of beads. This weather forecast contrasts Earth’s, where with the exception of a few deserts an umbrella may come in handy at any time and season. It is not entirely clear how Titan’s weather works and what created the dry shore lines and extensive rivers that the Cassini Huygens mission witnesses under Titan’s largely clear skies. Dr. Griffith’s present work aims to characterize the clouds, circulation, surface humidity and the stability of the atmosphere to understand the moon’s exotic weather.

Additional efforts aim to quantify the mass and location of organic material that precipitates to the surface from the stratosphere. Surface sediments are produced from byproducts of the photolysis of methane, which depletes the methane inventory fast enough to obliterate the atmospheric supply in 10 million years. The sediments are thus vestiges of the past presence of methane in Titan’s atmosphere. The present lack of oceans or apparent surface liquids suggests that methane is supplied by recent cryo-volcanism. But it is still not clear how long Titan has had methane in its atmosphere. Surface sediments are observed in the form of extensive dunes. Yet, instead of dune-forming particulates, we expected the 80% of the surface sediments to be liquid ethane, the main product of methane photolysis. Recent work by Dr. Griffith suggests that ethane precipitates only in Titan's polar regions. Thus perhaps lack of lakes in Titan's well-imaged tropics occurs because ethane instead accumulates at the poles as lakes or ice caps depending on the polar surface temperatures.

Dr. Griffith has also investigated the atmospheres of Jupiter, Saturn and their cousins, brown dwarfs.

CV for Dr. Griffith (PDF)

CURRENT SPACECRAFT INVOLVEMENT

Cassini

ADS PUBLICATIONS SEARCH

NASA ADS Author search: Caitlin A. Griffith

SELECTED PUBLICATIONS

Zellem, R. T., et al. The 4.5 μm Full-orbit Phase Curve of the Hot Jupiter HD 209458b 2014ApJ...790...53Z

Lorenz, R. D. Meteoritics and Planetary Science,t82 Book Review: Titan: Interior, surface, atmosphere, and space environment, edited by I. Müller-Wodarg, C. A. Griffith, E. Lellouch, and T. E. Cravens. Cambridge, UK: Cambridge University Press, 2014 474pp. $135, hardcover (ISBN #978-0521199926). 2014M&PS..tmp...82L

Teske, J. K., et al. C/O Ratios of Stars with Transiting Hot Jupiter Exoplanets 2014ApJ...788...39T

Teske, J. K., et al. Carbon and Oxygen Abundances in Cool Metal-rich Exoplanet Hosts: A Case Study of the C/O Ratio of 55
Cancri 2013ApJ...778..132T

Teske, J. K., Turner, J. D., Mueller, M., Griffith, C. A. Optical observations of the transiting exoplanet GJ 1214b 2013MNRAS.431.1669T

Tinetti, G., Tennyson, J., Griffith, C. A., Waldmann, I. Water in exoplanets 2012RSPTA.370.2749T

Teske, J. K., et al. Optical observations of the transiting exoplanet GJ 1214b 2013MNRAS.431.1669T

Teske, J. K., et al. Carbon and Oxygen Abundances in the Hot Jupiter Exoplanet Host Star XO-2B and Its Binary Companion 2013ApJ...768L..12T

Tinetti, G., et al. EChO. Exoplanet characterisation observatory2012ExA....34..311T

Soderblom, J. M., et al. Modeling specular reflections from hydrocarbon lakes on Titan 2012Icar..220..744S

Griffith, C. A., et al. Possible tropical lakes on Titan from observations of dark terrain 2012Natur.486..237G

Griffith, C. A., et al. Radiative transfer analyses of Titan's tropical atmosphere2012Icar..218..975G

Le Mouélic, S., et al. Dissipation of Titan's north polar cloud at northern spring equinox 2012P&SS...60...86L

Waldmann, I. P., et al. Ground-based Near-infrared Emission Spectroscopy of HD 189733b 2012ApJ...744...35W

Rodriguez, S., et al. Titan's cloud seasonal activity from winter to spring with Cassini/VIMS 2011Icar..216...89R

Lavvas, P., Griffith, C. A., Yelle, R. V.Condensation in Titan's atmosphere at the Huygens landing site 2011Icar..215..732L

Moses, J. I., et al. Disequilibrium Carbon, Oxygen, and Nitrogen Chemistry in the Atmospheres of HD 189733b and HD 209458b 2011ApJ...737...15M

Beaulieu, J.-P., et al. Methane in the Atmosphere of the Transiting Hot Neptune GJ436B? 2011ApJ...731...16B

Mousis, O., et al. On the Volatile Enrichments and Heavy Element Content in HD189733b 2011ApJ...727...77M

Beaulieu, J. P., et al. Water in the atmosphere of HD 209458b from 3.6-8 μm IRAC photometric observations in primary transit 2010MNRAS.409..963B

Lavvas, P., Yelle, R. V., Griffith, C. A. Titan’s vertical aerosol structure at the Huygens landing site: Constraints on particle size, density, charge, and refractive index 2010Icar..210..832L

Stephan, K., et al. Specular reflection on Titan: Liquids in Kraken Mare 2010GeoRL..3707104S

Tinetti, G., et al. Probing the Terminator Region Atmosphere of the Hot-Jupiter XO-1b with Transmission Spectroscopy 2010ApJ...712L.139T

Penteado, P. F., et al. Latitudinal variations in Titan’s methane and haze from Cassini VIMS observations 2010Icar..206..352P

Penteado, P. F., Griffith, C. A. Ground-based measurements of the methane distribution on Titan 2010Icar..206..345P

Swain, M. R., et al. A ground-based near-infrared emission spectrum of the exoplanet HD189733b 2010Natur.463..637S

Tinetti, G., et al. Exploring extrasolar worlds: from gas giants to terrestrial habitable planets 2010FaDi..147..369T

McKay, C. P., et al. Comparing methane and temperature profiles on Titan in 1980 and 2005 2009P&SS...57.1996M

Barnes, J. W., et al. VIMS spectral mapping observations of Titan during the Cassini prime mission 2009P&SS...57.1950B

Mousis, O., et al. Elemental abundances and minimum mass of heavy elements in the envelope of HD 189733b 2009A&A...507.1671M

Swain, M. R., et al. Water, Methane, and Carbon Dioxide Present in the Dayside Spectrum of the Exoplanet HD 209458b 2009ApJ...704.1616S

Griffith, C. A., et al. Characterization of Clouds in Titan's Tropical Atmosphere 2009ApJ...702L.105G

Boudon, V., et al. Methane in Titan's atmosphere: from fundamental spectroscopy to planetology 2009ENews..40...17B

Rodriguez, S., et al. Global circulation as the main source of cloud activity on Titan 2009Natur.459..678R

Coustenis, A., et al. TandEM: Titan and Enceladus mission 2009ExA....23..893C

Griffith, C. A. Storms, polar deposits and the methane cycle in Titan's atmosphere 2009RSPTA.367..713G

Griffith, C. A., McKay, C. P., Ferri, F. Titan's Tropical Storms in an Evolving Atmosphere 2008ApJ...687L..41G

Jaumann, R., et al. Fluvial erosion and post-erosional processes on Titan 2008Icar..197..526J

Graves, S. D. B., et al. Rain and hail can reach the surface of Titan 2008P&SS...56..346G

Ádámkovics, M., et al. Correction to "Titan's bright spots: Multiband spectroscopic measurement of surface diversity and hazes" 2008JGRE..11302S90A

Jaumann, R., et al. Distribution of icy particles across Enceladus' surface as derived from Cassini-VIMS measurements 2008Icar..193..407J

Coradini, A., et al. Identification of spectral units on Phoebe 2008Icar..193..233C

The Cassini Vims Team, et al. Composition of Titan's surface from Cassini VIMS 2006P&SS...54.1524T

McCord, T. B., et al. Composition of Titan's surface from Cassini VIMS 2006P&SS...54.1524M

Jaumann, R., et al. High-resolution CASSINI-VIMS mosaics of Titan and the icy Saturnian satellites 2006P&SS...54.1146J

Griffith, C. A., et al. Evidence for a Polar Ethane Cloud on Titan2006Sci...313.1620G

Griffith, C. A. Planetary science: Titan's exotic weather 2006Natur.442..362G

Ádámkovics, M., et al. Titan's bright spots: Multiband spectroscopic measurement of surface diversity and hazes 2006JGRE..11107S06A

Brown, R. H., et al. Observations in the Saturn system during approach and orbital insertion, with Cassini's visual and infrared mapping spectrometer (VIMS) 2006A&A...446..707B

Griffith, C. A., et al. The Evolution of Titan's Mid-Latitude Clouds 2005Sci...310..474G

Barnes, J. W., et al. A 5-Micron-Bright Spot on Titan: Evidence for Surface Diversity 2005Sci...310...92B

Greathouse, T. K., et al. Meridional variations of temperature, C2H2 and C2H6 abundances in Saturn's stratosphere at southern summer solstice 2005Icar..177...18G

Griffith, C. A., et al. Observations of Titan's Mesosphere 2005ApJ...629L..57G

Penteado, P. F., et al. Measurements of CH3D and CH4 in Titan from Infrared Spectroscopy 2005ApJ...629L..53P

Baines, K. H., et al. The Atmospheres of Saturn and Titan in the Near-Infrared First Results of Cassini/vims 2005EM&P...96..119B

Lorenz, R. D., et al. Convective plumes and the scarcity of Titan's clouds 2005GeoRL..3201201L

Ádámkovics, M., et al. Spatially-resolved spectroscopy at 1.6 μm of Titan's atmosphere and surface 2004GeoRL..3117S05A

Griffith, C. A., et al. Meridional transport of HCN from SL9 impacts on Jupiter 2004Icar..170...58G

Yelle, R. V., Griffith, C. A. HCN fluorescence on Titan 2003Icar..166..107Y

Bétrémieux, Y., Yelle, R. V., Griffith, C. A. HST observation of the atmospheric composition of Jupiter's equatorial region: evidence for tropospheric C2H2* 2003Icar..163..414B

Griffith, C. A., et al. Evidence for the Exposure of Water Ice on Titan's Surface 2003Sci...300..628G

Geballe, T. R., et al. High-Resolution 3 Micron Spectroscopy of Molecules in the Mesosphere and Troposphere of Titan 2003ApJ...583L..39G

Brown, M. E., Bouchez, A. H., Griffith, C. A. Direct detection of variable tropospheric clouds near Titan's south pole 2002Natur.420..795B

Yelle, R. V., Griffith, C. A., Young, L. A. Structure of the Jovian Stratosphere at the Galileo Probe Entry Site 2001Icar..152..331Y

Griffith, C. A., Hall, J. L., Geballe, T. R. Detection of Daily Clouds on Titan 2000Sci...290..509G

Griffith, C. A., Yelle, R. V. Equilibrium Chemistry in a Brown Dwarf's Atmosphere: Cesium in Gliese 229B 2000ApJ...532L..59G

Griffith, C. A., Yelle, R. V. Disequilibrium Chemistry in a Brown Dwarf's Atmosphere: Carbon Monoxide in Gliese 229B 1999ApJ...519L..85G

Griffith, C. A., Yelle, R. V., Marley, M. S. The Dusty Atmosphere of the Brown Dwarf Gliese 229B 1998Sci...282.2063G

Griffith, C. A., Transient clouds in Titan's lower atmosphere 1998Natur.395..575G

Lara, L.-M., et al. High-Resolution 10-micronmeter Spectroscopy of Ammonia and Phosphine Lines on Jupiter 1998Icar..131..317L

McKay, C. P., Martin, S. C., Griffith, C. A., Keller, R. M. Temperature Lapse Rate and Methane in Titan's Troposphere 1997Icar..129..498M

Griffith, C. A., et al. Thermal Infrared Imaging Spectroscopy of Shoemaker-Levy 9 Impact Sites: Spatial and Vertical Distributions of NH_3, C_2H_4, and 10-μm Dust Emission 1997Icar..128..275G

Noll, K. S., et al. Carbon Monoxide in Jupiter after Comet Shoemaker-Levy 9 1997Icar..126..324N

Bezard, B., Griffith, C. A., Kelly, D. M. Search for NH_3 in Jupiter's Stratosphere Ten Months after SL9's Collision 1997Icar..125..331B

Bezard, B., Griffith, C. A., Kelly, D. M., Lacy, J. H., Greathouse, T., Orton, G. Icarus, Thermal Infrared Imaging Spectroscopy of Shoemaker-Levy 9 Impact Sites: Temperature and HCN Retrievals 1997Icar..125...94B

Lissauer, J. J., et al. The epsilon Aurigae Secondary: A Hydrostatically Supported Disk 1996ApJ...465..371L

Orton, G., et al. Collision of Comet Shoemaker-Levy 9 with Jupiter Observed by the NASA Infrared Telescope Facility 1995Sci...267.1277O

Griffith, C. A., Zahnle, K. Influx of cometary volatiles to planetary moons: The atmospheres of 1000 possible Titans 1995JGR...10016907G

Griffith, C. A. Evidence for surface heterogeneity on Titan 1993Natur.364..511G

Griffith, C. A., et al. The tropospheric abundances of NH3 and PH3 in Jupiter's Great Red Spot, from Voyager IRIS observations 1992Icar...98...82G

Toon, O. B., et al. A physical model of Titan's aerosols 1992Icar...95...24T

Griffith, C. A., Owen, T., Wagener, R. Titan's surface and troposphere, investigated with ground-based, near-infrared observations 1991Icar...93..362G

Griffith, C. A. Investigations of Titan's troposphere and surface and Jupiter's great red SPOT with infrared observations 1991PhDT.........9G

Lissauer, J. J., Griffith, C. A. Erosion of circumstellar particle disks by interstellar dust 1989ApJ...340..468L