An equatorial oscillation in Saturn's middle atmosphere
Abstract
The middle atmospheres of planets are driven by a combination of radiative heating and cooling, mean meridional motions, and vertically propagating waves (which originate in the deep troposphere). It is very difficult to model these effects and, therefore, observations are essential to advancing our understanding of atmospheres. The equatorial stratospheres of Earth and Jupiter oscillate quasi-periodically on timescales of about two and four years, respectively, driven by wave-induced momentum transport. On Venus and Titan, waves originating from surface-atmosphere interaction and inertial instability are thought to drive the atmosphere to rotate more rapidly than the surface (superrotation). However, the relevant wave modes have not yet been precisely identified. Here we report infrared observations showing that Saturn has an equatorial oscillation like those found on Earth and Jupiter, as well as a mid-latitude subsidence that may be associated with the equatorial motion. The latitudinal extent of Saturn's oscillation shows that it obeys the same basic physics as do those on Earth and Jupiter. Future highly resolved observations of the temperature profile together with modelling of these three different atmospheres will allow us determine the wave mode, the wavelength and the wave amplitude that lead to middle atmosphere oscillation.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The Equatorial Zone has quasi-periodic thermal oscillations in the stratosphere that occur both in altitude and in time.
“as well as quasi-periodic thermal oscillations in the stratosphere that occur both in altitude and in time (Fouchet et al., 2008; Orton et al., 2008; Guerlet et al., 2018).”
From Saturn atmospheric dynamics one year after Cassini: Long-lived features and time variations in the drift of the Hexagon (2020) · cites this paper as Fouchet et al., 2008
The narrow and intense jet in the upper hazes and its temporal variations could be related to the equatorial thermal oscillations.
“the narrow and intense jet in the upper hazes and its temporal variations could be related to the equatorial thermal oscillations (Fouchet et al., 2008; Orton et al., 2008; Guerlet et al., 2018).”
From Saturn atmospheric dynamics one year after Cassini: Long-lived features and time variations in the drift of the Hexagon (2020) · cites this paper as Fouchet et al., 2008
Cites
(1987) · International geophysics/International geophysics series · doi:10.1016/c2009-0-61305-2 · Cited by 2,792 · see citing works
The quasi‐biennial oscillation
Baldwin, M., Gray, L. J., Dunkerton, T. J., Hamilton, K., Haynes, P., Randel, W. J., Holton, J. R., Alexander, M. J., Hirota, I., Horinouchi, T., et al. (2001) · Reviews of Geophysics · doi:10.1029/1999rg000073 · Cited by 2,119 · see citing works
Conrath, B. J. (1988) · Icarus · doi:10.1016/0019-1035(88)90078-4 · Cited by 755 · see citing works
Exploring The Saturn System In The Thermal Infrared: The Composite Infrared Spectrometer
Flasar, F., Kunde, V., Abbas, M., Achterberg, R., Ade, P., Barucci, A., Bézard, B., Bjoraker, G., Brasunas, J., Calcutt, S., et al. (2004) · Space Science Reviews · doi:10.1007/s11214-004-1454-9 · Cited by 313 · see citing works
Improving the Anelastic Approximation
Durran, D. R. (1989) · Journal of the Atmospheric Sciences · doi:10.1175/1520-0469(1989)046 · Cited by 301 · see citing works
Temperatures, Winds, and Composition in the Saturnian System
Flasar, F. M., Achterberg, R. K., Conrath, B. J., Pearl, J. C., Bjoraker, G. L., Jennings, D. E., Romani, P. N., Simon, A. A., Kunde, V. G., Nixon, C. A., et al. (2004) · Science · doi:10.1126/science.1105806 · Cited by 180 · see citing works
Temperature and circulation in the stratosphere of the outer planets
Conrath, B. J., Gierasch, P. J., & Leroy, S. S. (1990) · Icarus · doi:10.1016/0019-1035(90)90068-k · Cited by 154 · see citing works
The quasiquadrennial oscillation of Jupiter's equatorial stratosphere
Leovy, C. Β., Friedson, A. J., & Orton, G. S. (1991) · Nature · doi:10.1038/354380a0 · Cited by 127 · see citing works
An intense stratospheric jet on Jupiter
Flasar, F. M., Kunde, V. G., Achterberg, R. K., Conrath, B. J., Simon, A. A., Nixon, C. A., Gierasch, P. J., Romani, P. N., Bézard, B., Irwin, P. G. J., et al. (2004) · Nature · doi:10.1038/nature02142 · Cited by 121 · see citing works
Orton, G. S., Friedson, A. J., Baines, K. H., Martin, T. Z., West, R. A., Caldwell, J., Hammel, H. B., Bergstralh, J. T., Malcom, M. E., Golisch, W. F., et al. (1991) · Science · doi:10.1126/science.252.5005.537 · Cited by 104 · see citing works
Semi-annual oscillations in Saturn's low-latitude stratospheric temperatures
Orton, G. S., Yanamandra-Fisher, P. A., Fisher, B. M., Friedson, A. J., Parrish, P. D., Nelson, J. F., Bauermeister, A. S., Fletcher, L., Gezari, D. Y., Varosi, F., et al. (2008) · Nature · doi:10.1038/nature06897 · Cited by 94 · see citing works
Moses, J. I., & Greathouse, T. K. (2005) · Journal of Geophysical Research: Planets · doi:10.1029/2005je002450 · Cited by 76 · see citing works
New Observations and Modelling of a QBO-Like Oscillation in Jupiter's Stratosphere
Friedson, A. J. (1999) · Icarus · doi:10.1006/icar.1998.6038 · Cited by 60 · see citing works
Dickinson, R. E., & Ridley, E. C. (1972) · Journal of the Atmospheric Sciences · doi:10.1175/1520-0469(1972)029 · Cited by 59 · see citing works
Greathouse, T. K., Lacy, J. H., Bézard, B., Moses, J. I., Griffith, C. A., & Richter, M. J. (2005) · Icarus · doi:10.1016/j.icarus.2005.02.016 · Cited by 58 · see citing works
The onset and growth of the 1990 equatorial disturbance on Saturn
Beebe, R. F., Barnet, C. D., Sada, P. V., & Murrell, A. S. (1992) · Icarus · doi:10.1016/0019-1035(92)90035-6 · Cited by 48 · see citing works
A seasonal climate model of the atmospheres of the giant planets at the voyager encounter time
Bézard, B., & Gautier, D. (1985) · Icarus · doi:10.1016/0019-1035(85)90110-1 · Cited by 46 · see citing works
Planetary-Scale Thermal Waves in Saturn's Upper Troposphere
Achterberg, R. K., & Flasar, F. M. (1996) · Icarus · doi:10.1006/icar.1996.0024 · Cited by 40 · see citing works
A mechanistic model of the quasi-quadrennial oscillation in Jupiter’s stratosphere
Li, X., & Read, P. L. (2000) · Planetary and Space Science · doi:10.1016/s0032-0633(00)00033-7 · Cited by 39 · see citing works
Wind variations in Jupiter's equatorial atmosphere: A QQO counterpart?
Simon, A. A., Poston, B. W., Orton, G. S., & Fisher, B. M. (2006) · Icarus · doi:10.1016/j.icarus.2006.08.009 · Cited by 36 · see citing works
A seasonal radiative-dynamic model of Saturn's troposphere
Barnet, C. D., Beebe, R. F., & Conrath, B. J. (1992) · Icarus · doi:10.1016/0019-1035(92)90210-x · Cited by 34 · see citing works
Observations of Saturn's ribbon wave 14 years after its discovery
Sanchez-Lavega, A. (2002) · Icarus · doi:10.1006/icar.2002.6864 · Cited by 13 · see citing works
Vertically Propagating Waves in the Upper Atmosphere of Saturn From Cassini Radio Occultations
Schinder, P. J., Flasar, F. M., Kliore, A. J., French, R. G., Marouf, E. A., Nagy, A. F., Rappaport, N. J., Anabtawi, A., Asmar, S. W., Barbinis, E., et al. (2005) · AGUFM · Cited by 1 · see citing works
Analytic Studies of Cloud Droplet Coalescence I
Scott, W. T. (1968) · Journal of the Atmospheric Sciences · doi:10.1175/1520-0469(1968)025
Haynes (1991) · doi:10.1175/1520-0469(1991)048
Flagged first, then by citations
Cited by
Sorted by citations
Vision and Voyages for Planetary Science in the Decade 2013-2022
National Research Council (2011) · National Academies Press eBooks · doi:10.17226/13117 · Cited by 357 · see citing works
Phosphine on Jupiter and Saturn from Cassini/CIRS
Fletcher, L. N., Orton, G. S., Teanby, N. A., & Irwin, P. G. J. (2009) · Icarus · doi:10.1016/j.icarus.2009.03.023 · Cited by 190 · see citing works
Fletcher, L. N., Greathouse, T. K., Orton, G. S., Sinclair, J., Giles, R., Irwin, P. G. J., & Encrenaz, T. A. (2016) · Icarus · doi:10.1016/j.icarus.2016.06.008 · Cited by 133 · see citing works
“On Saturn, Cassini has observed the stratospheric airmasses associated with its quasi-periodic oscillation to sink towards the tropopause over time (Fouchet et al., 2008; Orton et al., 2008; Fletcher et al., 2010a; Guerlet et al., 2011; Schinder et al., 2011; Fletcher et al., 2016), and Jupiter’s QQO may be responsibl…”
BackgroundGuerlet, S., Fouchet, T., Bézard, B., Simon-Miller, A. A., & Michael Flasar, F. (2009) · Icarus · doi:10.1016/j.icarus.2009.04.002 · Cited by 98 · see citing works
“The main feature of the derived meridional profile is a local equatorial maximum of the temperature at 1 hPa, followed by a local minimum at 10−1 hPa, characteristic of an equatorial stratospheric oscillation (Fouchet et al., 2008).”
BackgroundMethodInfluentialSelf-citationAtmospheric regimes and trends on exoplanets and brown dwarfs
Zhang, X. (2020) · Research in Astronomy and Astrophysics · doi:10.1088/1674-4527/20/7/99 · Cited by 100 · see citing works
“…on Earth (quasi-biennial oscillation, QBO, with a period of∼2 years, Baldwin et al. 2001), Jupiter (quasi-quadrennial oscillation, QQO, with a period of ∼4 years, Leovy et al. 1991), and Saturn (the semiannual oscillation, SAO, with a period of ∼15 years, Orton et al. 2008; Fouchet et al. 2008).”
BackgroundSemi-annual oscillations in Saturn's low-latitude stratospheric temperatures
Orton, G. S., Yanamandra-Fisher, P. A., Fisher, B. M., Friedson, A. J., Parrish, P. D., Nelson, J. F., Bauermeister, A. S., Fletcher, L., Gezari, D. Y., Varosi, F., et al. (2008) · Nature · doi:10.1038/nature06897 · Cited by 94 · see citing works
Showman, A. P., Tan, X., & Zhang, X. (2019) · The Astrophysical Journal · doi:10.3847/1538-4357/ab384a · Cited by 86 · see citing works
“The QBO-type oscillations for the two simulations in Figure 6 exhibit periods of 12 and 19 years, which bracket the 15-year period for Saturn’s SAO (Orton et al. 2008; Fouchet et al. 2008; Guerlet et al. 2011).”
BackgroundMethodKouyama, T., Imamura, T., Nakamura, M., Satoh, T., & Futaana, Y. (2012) · Journal of Geophysical Research Planets · doi:10.1029/2011je004013 · Cited by 86 · see citing works
“Equatorial oscillations have also been suggested in Saturn atmosphere [Orton et al., 2008; Fouchet et al., 2008].”
BackgroundMapping potential vorticity dynamics on saturn: Zonal mean circulation from Cassini and Voyager data
Read, P. L., Conrath, B. J., Fletcher, L. N., Gierasch, P. J., Simon-Miller, A. A., & Zuchowski, L. C. (2009) · Planetary and Space Science · doi:10.1016/j.pss.2009.03.004 · Cited by 82 · see citing works
Seasonal change on Saturn from Cassini/CIRS observations, 2004–2009
Fletcher, L. N., Achterberg, R. K., Greathouse, T. K., Orton, G. S., Conrath, B. J., Simon-Miller, A. A., Teanby, N., Guerlet, S., Irwin, P. G. J., & Flasar, F. M. (2010) · Icarus · doi:10.1016/j.icarus.2010.01.022 · Cited by 77 · see citing works
The origin and evolution of Saturn’s 2011–2012 stratospheric vortex
Fletcher, L. N., Hesman, B. E., Achterberg, R. K., Irwin, P. G. J., Bjoraker, G. L., Gorius, N., Hurley, J., Sinclair, J., Orton, G. S., Legarreta, J., et al. (2012) · Icarus · doi:10.1016/j.icarus.2012.08.024 · Cited by 77 · see citing works
“12 also shows that the equatorial stratosphere is cooler than 10 N in August 2011, consistent with the continued downward propagation of the thermal structures associated with Saturn’s Semiannual Oscillation (SSAO, Orton et al., 2008; Fouchet et al., 2008; Fletcher et al., 2010; Guerlet et al., 2011; Friedson and Mose…”
BackgroundSaturn Atmospheric Structure and Dynamics
C, A. D. D. G., Achterberg, R. K., Baines, K. H., Flasar, F. M., Read, P. L., Sánchez-Lavega, A., & Showman, A. P. (2009) · Springer eBooks · doi:10.1007/978-1-4020-9217-6_6 · Cited by 72 · see citing works
Retrievals of atmospheric variables on the gas giants from ground-based mid-infrared imaging
Fletcher, L. N., Orton, G. S., Yanamandra-Fisher, P. A., Fisher, B. M., Parrish, P., & Irwin, P. G. J. (2008) · Icarus · doi:10.1016/j.icarus.2008.11.019 · Cited by 73 · see citing works
Global climate modeling of Saturn’s atmosphere. Part I: Evaluation of the radiative transfer model
Guerlet, S., Spiga, A., Sylvestre, M., Indurain, M., Fouchet, T., Leconte, J., Millour, E., Wordsworth, R., Capderou, M., Bézard, B., et al. (2014) · Icarus · doi:10.1016/j.icarus.2014.05.010 · Cited by 73 · see citing works
Self-citationScientific rationale for Saturn's in situ exploration
Mousis, O., Fletcher, L., Lebreton, J., Wurz, P., Cavali'e, T., Coustenis, A., Courtin, R., Gautier, D., Helled, R., Irwin, P., et al. (2014) · Planetary and Space Science · doi:10.1016/j.pss.2014.09.014 · Cited by 58 · see citing works
“On the other hand, both scenarios predict the same 14N/15N ratio at Jupiter and Saturn as the two planets accreted their nitrogen essentially from the same volatile reservoirs.”
InfluentialSpiga, A., Guerlet, S., Millour, E., Indurain, M., Meurdesoif, Y., Cabanes, S., Dubos, T., Leconte, J., Boissinot, A., Lebonnois, S., et al. (2019) · Icarus · doi:10.1016/j.icarus.2019.07.011 · Cited by 55 · see citing works
“, 2016), an equatorial oscillation of temperature in Saturn’s stratosphere (Fouchet et al., 2008; Guerlet et al., 2011; Li et al., 2011) with semi-annual periodicity (Orton et al.”
Atmospheric structure and helium abundance on Saturn from Cassini/UVIS and CIRS observations
Koskinen, T., & Guerlet, S. (2018) · Icarus (New York, N.Y. 1962) · doi:10.1016/j.icarus.2018.02.020 · Cited by 51 · see citing works
Decadal variations in a Venus general circulation model
Parish, H. F., Schubert, G., Covey, C., Walterscheid, R. L., Grossman, A., & Lebonnois, S. (2010) · Icarus · doi:10.1016/j.icarus.2010.11.015 · Cited by 57 · see citing works
“, 2004), and a 13–16 (Earth) year oscillation has recently been found on Saturn (Fouchet et al., 2008; Orton et al., 2008).”
BackgroundInfluentialGuerlet, S., Fouchet, T., Bézard, B., Flasar, F. M., & Simon, A. A. (2011) · Geophysical Research Letters · doi:10.1029/2011gl047192 · Cited by 56 · see citing works
“We also show, for comparison, the map we previously obtained from limb data acquired between March, 2005 and February, 2006 [see Fouchet et al., 2008; Guerlet et al., 2009], as well as the difference between the two maps (Figure 1, right).”
ResultGeneral circulation and transport in Saturn’s upper troposphere and stratosphere
Friedson, A. J., & Moses, J. I. (2012) · Icarus · doi:10.1016/j.icarus.2012.02.004 · Cited by 54 · see citing works
Saturn’s variable thermosphere from Cassini/UVIS occultations
Koskinen, T. T., Sandel, B. R., Yelle, R. V., Strobel, D. F., Müller-Wodarg, I. C. F., & Erwin, J. T. (2015) · Icarus · doi:10.1016/j.icarus.2015.07.008 · Cited by 53 · see citing works
Self-citationSinclair, J. A., Irwin, P. G. J., Fletcher, L. N., Moses, J. I., Greathouse, T. K., Friedson, A. J., Hesman, B., Hurley, J., & Merlet, C. (2013) · Icarus · doi:10.1016/j.icarus.2013.03.011 · Cited by 49 · see citing works
Atmospheric chemistry on Uranus and Neptune
Moses, J. I., Cavalié, T., Fletcher, L. N., & Roman, M. T. (2020) · Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering Sciences · doi:10.1098/rsta.2019.0477 · Cited by 46 · see citing works
“circulation patterns [154–171].”
Guerlet, S., Fouchet, T., Bézard, B., Moses, J. I., Fletcher, L. N., Simon-Miller, A. A., & Michael Flasar, F. (2010) · Icarus · doi:10.1016/j.icarus.2010.03.033 · Cited by 45 · see citing works
“Downwelling at northern mid-latitudes was also suggested from CIRS observations of increased stratospheric temperatures (Fouchet et al., 2008).”
BackgroundSelf-citationTRAPPIST Habitable Atmosphere Intercomparison (THAI) Workshop Report
Fauchez, T. J., Turbet, M., Sergeev, D. E., Mayne, N. J., Spiga, A., Sohl, L. E., Saxena, P., Deitrick, R., Gilli, G., Domagal-Goldman, S. D., et al. (2021) · The Planetary Science Journal · doi:10.3847/psj/abf4df · Cited by 44 · see citing works
Disruption of Saturn’s quasi-periodic equatorial oscillation by the great northern storm
Fletcher, L. N., Guerlet, S., Orton, G. S., Cosentino, R. G., Fouchet, T., Irwin, P. G. J., Li, L., Flasar, F. M., Gorius, N., & Morales-Juberías, R. (2017) · Nature Astronomy · doi:10.1038/s41550-017-0271-5 · Cited by 44 · see citing works
Self-citationSaturn: Composition and Chemistry
Fouchet, T., Moses, J. I., & Conrath, B. J. (2009) · Springer eBooks · doi:10.1007/978-1-4020-9217-6_5 · Cited by 43 · see citing works
New Observations and Modeling of Jupiter's Quasi‐Quadrennial Oscillation
Cosentino, R., Morales-Juberías, R., Greathouse, T. K., Orton, G. S., Johnson, P., Fletcher, L. N., & Simon, A. A. (2017) · Journal of Geophysical Research Planets · doi:10.1002/2017je005342 · Cited by 43 · see citing works
Schinder, P. J., Flasar, F. M., Marouf, E. A., French, R. G., McGhee, C. A., Kliore, A. J., Rappaport, N. J., Barbinis, E., Fleischman, D. U., & Anabtawi, A. (2011) · Geophysical Research Letters · doi:10.1029/2011gl047191 · Cited by 43 · see citing works
“Similar evidence for an equatorial oscillation in Jupiter’s stratosphere was provided by ground‐based measurements [Orton et al., 1991; Friedson, 1999] and CIRS nadir sounding [Flasar et al., 2004] during Cassini’s 138 RJ swing by at the end of 2000.”
MethodDisruption of Saturn’s quasi-periodic equatorial oscillation by the great northern storm
(7627094), L. N. F., Guerlet, S., Orton, G. S., (7714907), R. G. C., Fouchet, T., Irwin, P. G. J., (229765), L. L., Flasar, F. M., (7714916), N. G., & (7714919), R. M.-J. (2017) · Figshare · Cited by 39 · see citing works
Giant Planet Observations with the <i>James Webb Space Telescope</i>
Norwood, J., Moses, J., Fletcher, L. N., Orton, G., Irwin, P. G. J., Atreya, S., Rages, K., Cavalié, T., Sánchez-Lavega, A., Hueso, R., et al. (2016) · Publications of the Astronomical Society of the Pacific · doi:10.1088/1538-3873/128/959/018005 · Cited by 38 · see citing works
From cold to warm gas giants: A three-dimensional atmospheric general circulation modeling
Medvedev, A. S., Sethunadh, J., & Hartogh, P. (2013) · Icarus · doi:10.1016/j.icarus.2013.03.028 · Cited by 37 · see citing works
First direct measurement of auroral and equatorial jets in the stratosphere of Jupiter
Cavalié, T., Benmahi, B., Hue, V., Moreno, R., Lellouch, E., Fouchet, T., Hartogh, P., Rezac, L., Greathouse, T. K., Gladstone, G. R., et al. (2021) · Astronomy and Astrophysics · doi:10.1051/0004-6361/202140330 · Cited by 37 · see citing works
Atmospheric chemistry on Uranus and Neptune
(7678232), J. M., (7714670), T. C., (7625672), L. F., & (8615760), M. R. (2020) · Figshare · Cited by 35 · see citing works
Stratospheric benzene and hydrocarbon aerosols detected in Saturn’s auroral regions
Guerlet, S., Fouchet, T., Vinatier, S., Simon, A. A., Dartois, E., & Spiga, A. (2015) · Astronomy & Astrophysics · doi:10.1051/0004-6361/201424745 · Cited by 32 · see citing works
“…in 2005−2010 (mostly at a 7.5 cm−1 resolution) have been used to retrieve vertical profiles of the stratospheric temperature and of the abundance of five hydrocarbons (C2H6, C2H2, C3H8, CH3C2H, C4H2), the main by-products of methane photolysis (Fouchet et al. 2008; Guerlet et al. 2009, 2010).”
MethodInfluentialSelf-citationSeasonal changes in Saturn’s stratosphere inferred from Cassini/CIRS limb observations
Sylvestre, M., Guerlet, S., Fouchet, T., Spiga, A., Flasar, F. M., Hesman, B., & Bjoraker, G. L. (2015) · Icarus · doi:10.1016/j.icarus.2015.05.025 · Cited by 32 · see citing works
“These differences between the measured and predicted temperatures are expected, as our radiative–convective model cannot reproduce temperatures perturbations induced by the equatorial oscillation, which is suggested to be a purely dynamical effect (Fouchet et al., 2008; Guerlet et al., 2011). In the northern hemispher…”
InfluentialCassini Exploration of the Planet Saturn: A Comprehensive Review
Ingersoll, A. P. (2020) · Space Science Reviews · doi:10.1007/s11214-020-00751-1 · Cited by 32 · see citing works
Guerlet, S., Fouchet, T., Spiga, A., Flasar, F. M., Fletcher, L. N., Hesman, B. E., & Gorius, N. (2018) · Journal of Geophysical Research Planets · doi:10.1002/2017je005419 · Cited by 30 · see citing works
Strong jet and a new thermal wave in Saturn's equatorial stratosphere
Li, L., Gierasch, P. J., Achterberg, R. K., Conrath, B. J., Flasar, F. M., Vasavada, A. R., Ingersoll, A. P., Banfield, D., Simon, A. A., & Fletcher, L. N. (2008) · Geophysical Research Letters · doi:10.1029/2008gl035515 · Cited by 30 · see citing works
“If we take the possible decrease of � 100 m/s around 10 mbar from Cassini limb observations [ Fouchet et al., 2008 ] into account, the equatorial wave in the stratosphere still moves westward with a velocity � 30 m/s relative to the strong background current (Cx � u = � 30 m/s).”
BackgroundMethodResultInfluentialSaturn’s upper atmosphere during the Voyager era: Reanalysis and modeling of the UVS occultations
Vervack, R. J., & Moses, J. I. (2015) · Icarus · doi:10.1016/j.icarus.2015.06.007 · Cited by 30 · see citing works
“The Cassini mission has provided a wealth of information on stratospheric temperatures (e.g., Flasar et al., 2005; Fletcher et al., 2007; Fletcher et al., 2008, 2010; Fouchet et al., 2008; Liming et al., 2008; Li et al., 2013; Guerlet et al., 2009, 2010, 2011; Sinclair et al., 2013, 2014), but the results show signifi…”
BackgroundMethodInfluentialHue, V., Cavalié, T., Dobrijevic, M., Hersant, F., & Greathouse, T. K. (2015) · Icarus · doi:10.1016/j.icarus.2015.04.001 · Cited by 30 · see citing works
“The temperatures below the 10−5mbar pressure level come from a retrieval performed by Fouchet et al. (2008) on Cassini/CIRS data observed at a planetographic latitude of 20◦S. Extrapolation to the upper stratosphere has been made using data from Smith et al. (1983) (see Fig.”
BackgroundMethodInfluentialHerschel map of Saturn’s stratospheric water, delivered by the plumes of Enceladus
Cavalié, T., Hue, V., Hartogh, P., Moreno, R., Lellouch, E., Feuchtgruber, H., Jarchow, C., Cassidy, T., Fletcher, L. N., Billebaud, F., et al. (2019) · Astronomy and Astrophysics · doi:10.1051/0004-6361/201935954 · Cited by 29 · see citing works
From Voyager-IRIS to Cassini-CIRS: Interannual variability in Saturn’s stratosphere?
Sinclair, J., Irwin, P. G. J., Fletcher, L. N., Greathouse, T. K., Guerlet, S., Hurley, J., & Merlet, C. (2014) · Icarus · doi:10.1016/j.icarus.2014.02.009 · Cited by 28 · see citing works
“As shown, there are differences in temperature from 15◦S to 15◦N which represents the range of latitudes occupied by the SSAO [2].”
BackgroundEvolution of stratospheric chemistry in the Saturn storm beacon region
Moses, J. I., Armstrong, E. S., Fletcher, L. N., Friedson, A. J., Irwin, P. G. J., Sinclair, J., & Hesman, B. E. (2015) · Icarus · doi:10.1016/j.icarus.2015.08.012 · Cited by 28 · see citing works
Jet streams and tracer mixing in the atmospheres of brown dwarfs and isolated young giant planets
Tan, X. (2022) · Monthly Notices of the Royal Astronomical Society · doi:10.1093/mnras/stac344 · Cited by 27 · see citing works
An enduring rapidly moving storm as a guide to Saturn’s Equatorial jet’s complex structure
Sánchez-Lavega, A., Garcia‐Melendo, E., Pérez-Hoyos, S., Hueso, R., Wong, M. H., Simon, A. A., Sanz‐Requena, J. F., Antuñano, A., Barrado-Izagirre, N., Gárate-López, I., et al. (2016) · Nature Communications · doi:10.1038/ncomms13262 · Cited by 27 · see citing works
Generation of a mean flow by an internal wave
Semin, B., Facchini, G., Pétrélis, F., & Fauve, S. (2016) · Physics of Fluids · doi:10.1063/1.4962937 · Cited by 26 · see citing works
A strong high altitude narrow jet detected at Saturn's equator
Garcia‐Melendo, E., Sánchez-Lavega, A., Legarreta, J., Pérez-Hoyos, S., & Hueso, R. (2010) · Geophysical Research Letters · doi:10.1029/2010gl045434 · Cited by 26 · see citing works
“In Saturn the central jet is located at the base of a region where a biannual oscillation in the temperature field has been detected [Fouchet et al., 2008; Orton et al., 2008] and where a high altitude (1 mbar) stratospheric jet and a thermal wave have been reported [Li et al., 2008].”
BackgroundNonlinear saturation of the large scale flow in a laboratory model of the quasibiennial oscillation
Semin, B., Garroum, N., Pétrélis, F., & Fauve, S. (2018) · Physical Review Letters · doi:10.1103/physrevlett.121.134502 · Cited by 26 · see citing works
Fluctuations in Jupiter’s equatorial stratospheric oscillation
Antuñano, A., Cosentino, R., Fletcher, L. N., Simon, A. A., Greathouse, T. K., & Orton, G. S. (2020) · Nature Astronomy · doi:10.1038/s41550-020-1165-5 · Cited by 25 · see citing works
Moses, J. I., Brown, Z., Koskinen, T., Fletcher, L. N., Serigano, J., Guerlet, S., Moore, L., Waite, J. H., Jaffel, L. B., Galand, M. I., et al. (2022) · Icarus · doi:10.1016/j.icarus.2022.115328 · Cited by 25 · see citing works
Saturn's Atmosphere in Northern Summer Revealed by JWST/MIRI
Fletcher, L. N., King, O. R. T., Harkett, J., Hammel, H. B., Roman, M. T., Melin, H., Hedman, M. M., Moses, J. I., Guerlet, S., Milam, S. N., et al. (2023) · Journal of Geophysical Research Planets · doi:10.1029/2023je007924 · Cited by 25 · see citing works
“5 mbar, with the peak-to-peak contrast of ∼ 400 m/s between eastward and westward maxima being comparable to that derived from Cassini limb observations (Fouchet et al., 2008).”
BackgroundMethodInfluentialCoupled convection and internal gravity waves excited in water around its density maximum at 4°C
Léard, P., Favier, B., Gal, P. L., & Bars, M. L. (2020) · Physical Review Fluids · doi:10.1103/physrevfluids.5.024801 · Cited by 23 · see citing works
Vertically-resolved observations of Jupiter’s quasi-quadrennial oscillation from 2012 to 2019
Giles, R., Greathouse, T. K., Cosentino, R., Orton, G. S., & Lacy, J. H. (2020) · Icarus · doi:10.1016/j.icarus.2020.113905 · Cited by 23 · see citing works
“mentum to the QQO, agreeing with earlier results from Friedson (1999). In particular, Cosentino et al.”
ResultDobrijévic, M., Cavalié, T., & Billebaud, F. (2011) · Icarus · doi:10.1016/j.icarus.2011.04.027 · Cited by 23 · see citing works
“Introduction11 Recent Cassini and ground-based observations (Greathouse et al. 2005, Howett12 et al. 2007, Fouchet et al. 2008, Guerlet et al. 2009, Hesman et al. 2009, Guerlet13 et al. 2010) and observations gathered in the framework of the Herschel Guar-14 anteed Time Key Program ”Water and…”
BackgroundJupiter’s Atmospheric Variability from Long-term Ground-based Observations at 5 μm
Antuñano, A., Fletcher, L. N., Orton, G. S., Melin, H., Milan, S. E., ROGERS, J. H., Greathouse, T. K., Harrington, J., Donnelly, P. T., & Giles, R. (2019) · The Astronomical Journal · doi:10.3847/1538-3881/ab2cd6 · Cited by 22 · see citing works
“…oscillation (QBO) in Earth’s equatorial stratospheric winds and temperatures (e.g., Baldwin et al. 2001) and Saturn’s quasi-periodic equatorial oscillation (QPO; Fouchet et al. 2008; Orton et al. 2008), which has been observed to span almost down to Saturn’s tropopause (Fletcher et al. 2017a).”
BackgroundStrong Temporal Variation Over One Saturnian Year: From Voyager to Cassini
Li, L., Achterberg, R. K., Conrath, B. J., Gierasch, P. J., Smith, M. A., Simon, A. A., Nixon, C. A., Orton, G. S., Flasar, F. M., Jiang, X., et al. (2013) · Scientific Reports · doi:10.1038/srep02410 · Cited by 22 · see citing works
“The temporal variation of tropospheric temperature is also different from the semi-annual oscillations 17,18 , because the semi-annual oscillations were discovered in the middle and high stratosphere of Saturn.”
Equatorial winds on Saturn and the stratospheric oscillation
Li, L., Jiang, X., Ingersoll, A. P., C, A. D. D. G., Porco, C. C., West, R. A., Vasavada, A. R., Ewald, S. P., Conrath, B. J., Gierasch, P. J., et al. (2011) · Nature Geoscience · doi:10.1038/ngeo1292 · Cited by 22 · see citing works
Hue, V., Greathouse, T. K., Cavalié, T., Dobrijevic, M., & Hersant, F. (2016) · Icarus · doi:10.1016/j.icarus.2015.12.007 · Cited by 21 · see citing works
“Latitudes below ± 20◦ were not accounted for in order to remove the effects from SSAO on the observed temperatures.”
BackgroundInfluentialThe Global Atmospheric Circulation of Saturn
Showman, A. P., Ingersoll, A. P., Achterberg, R. K., & Kaspi, Y. (2018) · Cambridge University Press eBooks · doi:10.1017/9781316227220.011 · Cited by 21 · see citing works
“Fouchet et al. 2009, see also the chapter by Fletcher et al.34 in this volume).”
BackgroundHueso, R., Sánchez-Lavega, A., Rojas, J. F., Simon, A. A., Barry, T., Río-Gaztelurrutia, T. D., Antuñano, A., Sayanagi, K. M., Delcroix, M., Fletcher, L. N., et al. (2020) · Icarus · doi:10.1016/j.icarus.2019.113429 · Cited by 20 · see citing works
“and the equatorial thermal oscillations observed by the CIRS instrument (Fouchet et al., 2008; Orton et al., 2008; Guerlet et al., 2018) suggest that a thorough analysis of zonal winds with the best temporal resolution should be pursued with Cassini archived data complemented with cloud correlation analysis on current…”
BackgroundUnexpected long-term variability in Jupiter’s tropospheric temperatures
Orton, G. S., Antuñano, A., Fletcher, L. N., Sinclair, J., Momary, T., Fujiyoshi, T., Yanamandra-Fisher, P. A., Donnelly, P. T., Greco, J., Payne, A. V., et al. (2022) · Nature Astronomy · doi:10.1038/s41550-022-01839-0 · Cited by 20 · see citing works
Wentzel–Kramers–Brillouin approximation for atmospheric waves
Godin, O. A. (2015) · Journal of Fluid Mechanics · doi:10.1017/jfm.2015.367 · Cited by 20 · see citing works
“A different approach is necessary to obtain rigorous estimates of the deviation of the first WKB approximation from exact solutions at finite L, see Olver (1974), Fedoryuk (1987), Brekhovskikh & Godin (1998) and references therein.”
BackgroundMethodInfluentialGlobal climate modeling of Saturn’s atmosphere. Part IV: Stratospheric equatorial oscillation
Bardet, D., Spiga, A., Guerlet, S., Cabanes, S., Millour, E., & Boissinot, A. (2020) · Icarus · doi:10.1016/j.icarus.2020.114042 · Cited by 19 · see citing works
“Secondly, a crucial discovery of Cassini is that temperatures retrieved from thermal infrared spectra in Saturn’s stratosphere exhibit an equatorial oscillation with semi-annual periodicity (Orton et al., 2008; Fouchet et al., 2008).”
BackgroundSaturn: Atmosphere, Ionosphere, and Magnetosphere
Gombosi, T. I., & Ingersoll, A. P. (2010) · Science · doi:10.1126/science.1179119 · Cited by 19 · see citing works
Joint evolution of equatorial oscillation and interhemispheric circulation in Saturn’s stratosphere
Bardet, D., Spiga, A., & Guerlet, S. (2022) · Nature Astronomy · doi:10.1038/s41550-022-01670-7 · Cited by 17 · see citing works
“The TEM stream function is calculated by integrating equation (1) (normalized by the density ρ0) downward from the top level, assuming that v̄ is zero above that level35.”
MethodAn intense narrow equatorial jet in Jupiter’s lower stratosphere observed by JWST
Hueso, R., Sánchez-Lavega, A., Fouchet, T., de Pater, I., Antuñano, A., Fletcher, L. N., Wong, M. H., Rodríguez‐Ovalle, P., Sromovsky, L. A., Fry, P. M., et al. (2023) · Nature Astronomy · doi:10.1038/s41550-023-02099-2 · Cited by 17 · see citing works
“The perturbations to the equatorial stratospheric temperatures and inferred thermal winds vary periodically on multiyear timescales 15–18 , sharing characteristics with similar phenomena on Earth, such as the quasi-biennial oscillation (QBO) and semi-annual oscillation (SAO) 12,19 .”
InfluentialCowley, S. W. H., & Provan, G. (2013) · Journal of Geophysical Research Space Physics · doi:10.1002/2013ja019200 · Cited by 17 · see citing works
Saturn's global zonal winds explored by Cassini/VIMS 5-μm images
Studwell, A., Li, L., Jiang, X., Baines, K. H., Fry, P. M., Momary, T. W., & Dyudina, U. A. (2018) · Geophysical Research Letters · doi:10.1029/2018gl078139 · Cited by 16 · see citing works
“…(CIRS; Flasar, Kunde, Abbas, et al., 2004) and the thermal wind relationship (e.g., Achterberg et al., 2014; Flasar et al., 2005; Fletcher et al., 2010, 2011, 2016, 2017; Fouchet et al., 2008; Guerlet et al., 2011; Li et al., 2007, 2008, 2011, 2013; Read et al., 2007; Read, Conrath, et al., 2009).”
First absolute wind measurements in Saturn’s stratosphere from ALMA observations
Benmahi, B., Cavalié, T., Fouchet, T., Moreno, R., Lellouch, E., Bardet, D., Guerlet, S., Hue, V., & Spiga, A. (2022) · Astronomy and Astrophysics · doi:10.1051/0004-6361/202244200 · Cited by 16 · see citing works
Influence of solar activity on seasonal variations of methane absorption in the atmosphere of Saturn
Vidmachenko, A. P. (2015) · Kinematics and Physics of Celestial Bodies · doi:10.3103/s088459131503006x · Cited by 16 · see citing works
Harrington, J., French, R. G., & Matcheva, K. (2010) · The Astrophysical Journal · doi:10.1088/0004-637x/716/1/404 · Cited by 15 · see citing works
“…Fritts et al. 2006), Jupiter (French & Gierasch 1974; Young et al. 1997; Raynaud et al. 2003, 2004; Young et al. 2005), Saturn (Cooray et al. 1998; Fouchet et al. 2008), Titan (Sicardy et al. 1999), Uranus (Young et al. 2001), Neptune (Roques et al. 1994), and Pluto (Person et al. 2008; Hubbard…”
BackgroundMapping the zonal winds of Jupiter’s stratospheric equatorial oscillation
Benmahi, B., Cavalié, T., Greathouse, T. K., Hue, V., Giles, R., Guerlet, S., Spiga, A., & Cosentino, R. (2021) · Astronomy and Astrophysics · doi:10.1051/0004-6361/202141523 · Cited by 14 · see citing works
Cavalié, T., Dobrijévic, M., Fletcher, L. N., Loison, J., Hickson, K. M., Hue, V., & Hartogh, P. (2015) · Astronomy and Astrophysics · doi:10.1051/0004-6361/201425444 · Cited by 13 · see citing works
“It is perturbed by a thermal oscillation (Fouchet et al. 2008; Orton et al. 2008; Guerlet et al. 2011) and possibly by a seasonally reversing Hadley cell (Friedson & Moses 2012).”
BackgroundMultimodal Excitation to Model the Quasibiennial Oscillation.
Léard, P., Lecoanet, D., & Bars, M. L. (2020) · Physical Review Letters · doi:10.1103/physrevlett.125.234501 · Cited by 11 · see citing works
“Similar reversals are observed on other planets [11, 12].”
ResultFinite-amplitude acoustic-gravity waves: exact solutions
Godin, O. A. (2015) · Journal of Fluid Mechanics · doi:10.1017/jfm.2015.40 · Cited by 11 · see citing works
“These waves play an important role in the dynamics of stars and planetary atmospheres (Duvall et al. 1993; Podesta 2005; Fouchet et al. 2008) and have been extensively studied in meteorology, climate research and space physics contexts (Gossard & Hooke 1975; Hargreaves & Gadsden 1992; Fritts &…”
BackgroundDowling, T. E. (2008) · Nature · doi:10.1038/453163a · Cited by 10 · see citing works
Smith, C. (2013) · Icarus · doi:10.1016/j.icarus.2013.07.001 · Cited by 10 · see citing works
Saturn’s Seasonally Changing Atmosphere
Fletcher, L. N., Greathouse, T. K., Guerlet, S., Moses, J. I., & West, R. A. (2018) · Cambridge University Press eBooks · doi:10.1017/9781316227220.010 · Cited by 9 · see citing works
Saturn’s seasonal variability from four decades of ground-based mid-infrared observations
Blake, J., Fletcher, L. N., Orton, G. S., Antuñano, A., Roman, M. T., Kasaba, Y., Fujiyoshi, T., Melin, H., Bardet, D., Sinclair, J., et al. (2022) · Icarus · doi:10.1016/j.icarus.2022.115347 · Cited by 9 · see citing works
“Given the proposed semi-annual nature of the equatorial oscillation (Orton et al., 2008; Fouchet et al., 2008), our first-order assumption would be that Saturn should appear the same from one Saturnian year to the next.”
BackgroundMidsummer Atmospheric Changes in Saturn’s Northern Hemisphere from the Hubble OPAL Program
Simon, A. A., Hueso, R., Sánchez-Lavega, A., & Wong, M. H. (2021) · The Planetary Science Journal · doi:10.3847/psj/abe40f · Cited by 8 · see citing works
“This may be partially due to altitude changes and corresponding thermal wind shear (Pérez-Hoyos & Sánchez-Lavega 2006) or to quasiperiodic oscillations in the winds (Flasar et al. 2005; Fouchet et al. 2008).”
BackgroundReview of Knowledge Prior to the Cassini-Huygens Mission and Concurrent Research
Orton, G., Baines, K., Cruikshank, D., Cuzzi, J., Krimigis, S., Miller, S., & Lellouch, E. (2009) · Springer eBooks · doi:10.1007/978-1-4020-9217-6_2 · Cited by 14 · see citing works
“11 illustrates that the phase of this oscillation also appeared to be tied to Saturn’s equinox, and identified it as the manifestation of the vertical waves detected by the CIRS experiment in Saturn’s stratosphere (Fouchet et al. 2008).”
BackgroundA Chorus of the Winds—On Saturn!
Read, P. L. (2018) · Journal of Geophysical Research Planets · doi:10.1029/2018je005625 · Cited by 7 · see citing works
Diffraction of acoustic-gravity waves in the presence of a turning point
Godin, O. A. (2016) · The Journal of the Acoustical Society of America · doi:10.1121/1.4955283 · Cited by 6 · see citing works
Fluid dynamics of a mixed convective/stably stratified system—A review of some recent works
Bars, M. L., Couston, L., Favier, B., Léard, P., Lecoanet, D., & Gal, P. L. (2020) · Comptes rendus. Physique · doi:10.5802/crphys.17 · Cited by 6 · see citing works
“Similar oscillations have also been reported in Jupiter’s and Saturn’s atmospheres [5, 6].”
ResultQuasi-biennial oscillation: laboratory experiments
Semin, B., & Pétrélis, F. (2024) · Comptes rendus. Physique · doi:10.5802/crphys.195 · Cited by 6 · see citing works
Spatiotemporal Variability of Saturn's Zonal Winds Observed by Cassini
Wang, X., Li, L., Guan, L., Jiang, X., Fry, P. M., Dyudina, U. A., Fletcher, L. N., Garcia‐Melendo, E., Hueso, R., Morales-Juberías, R., et al. (2025) · Journal of Geophysical Research Planets · doi:10.1029/2024je008515 · Cited by 3 · see citing works
“…the classic thermal‐ wind equation, has been developed in recent studies (de la Torre Juarez et al., 2002; Flasar, Achterberg, Conrath, Gierasch, et al., 2005; Flasar, Achterberg, Conrath, Pearl, et al., 2005b; Fouchet et al., 2008; Galanti et al., 2017; Li et al., 2007, 2008; Marcus et al., 2019).”
InfluentialFundamental Science Achieved with a Single Probe in Each Giant Planet Atmosphere
Mandt, K. E., Simon, A. A., Mousis, O. J., Atkinson, D. H., & Hofstadter, M. (2024) · Space Science Reviews · doi:10.1007/s11214-024-01083-0 · Cited by 3 · see citing works
“However, both Jupiter and Saturn show stratospheric temperature and possibly wind oscillations, similar to wave processes occurring on Earth (e.g., Leovy et al. 1991; Orton et al. 1991; Fouchet et al. 2008).”
Zonons Are Solitons Produced by Rossby Wave Ringing
Cohen, N., Galperin, B., & Sukoriansky, S. (2024) · Atmosphere · doi:10.3390/atmos15060711 · Cited by 2 · see citing works
Ground-Based Observational Support for Spacecraft Exploration of the Outer Planets
Orton, G. S. (2009) · Earth Moon and Planets · doi:10.1007/s11038-009-9295-x · Cited by 2 · see citing works
COMMISSION 16: PHYSICAL STUDY OF PLANETS AND SATELLITES
Courtin, R., McGrath, M. A., Consolmagno, G. J., Blanco, C., Ksanfomality, L. V., Lara, L. M., Morrison, D., Spencer, J. R., & Tejfel, V. G. (2008) · Proceedings of the International Astronomical Union · doi:10.1017/s1743921308025416 · Cited by 2 · see citing works
Atmospheric Dynamics of Giants and Icy Planets
Sánchez-Lavega, A., & Heimpel, M. H. (2017) · Springer eBooks · doi:10.1007/978-3-319-30648-3_51-1 · Cited by 2 · see citing works
Large-scale flow driven by turbulently generated internal gravity waves
Léard, P., Margaillan, L., Raymond, T., Rouby, M., & Bars, M. L. (2021) · Physical Review Fluids · doi:10.1103/physrevfluids.6.084801 · Cited by 3 · see citing works
Atmospheric Dynamics of Giants and Icy Planets
Sánchez-Lavega, A., & Heimpel, M. H. (2018) · Springer eBooks · doi:10.1007/978-3-319-55333-7_51 · Cited by 2 · see citing works
Equatorial stratospheric oscillations in planetary atmospheres
Bardet, D., & Antuñano, A. (2024) · Elsevier eBooks · doi:10.1016/b978-0-443-15638-0.00018-6 · Cited by 1 · see citing works
The Strongest Jet Ever Detected and a New Thermal Wave in Saturn's Equatorial Stratosphere
Li, L., Gierasch, P. J., Achterberg, R. K., Conrath, B. J., Flasar, F. M., Vasavada, A. R., Ingersoll, A. P., Banfield, D., Simon, A. A., & Fletcher, L. N. (2008) · AAS/Division for Planetary Sciences Meeting Abstracts #40
Spatio-Temporal Pattern of Saturn's Equatorial Oscillation
Flasar, F. M., Schnider, P. J., Marouf, E. A., McGhee, C. A., Kliore, A. J., & Rappaport, N. J. (2010) · European Planetary Science Congress 2010
Evolution of the equatorial oscillation in Saturn's stratosphere
Guerlet, S., Fouchet, T., Bézard, B., Simon, A. A., & Flasar, F. M. (2010) · HAL
The Future Exploration of Saturn
Baines, K. H., Atreya, S. K., Crary, F. J., Edgington, S. G. C., Greathouse, T. K., Melin, H., Mousis, O. J., Orton, G. S., Spilker, T. R., & Wesley, A. (2018) · Cambridge University Press eBooks · doi:10.1017/9781316227220.014
“The distribution of stratospheric winds can be mapped in particular at 936 equatorial latitudes, possibly providing evidence of waves perhaps associated with the 937 semi-annual oscillation (Fouchet et al., 2008; Orton et al., 2008).”
Background
- Authors
- Fouchet, T., Guerlet, S., Strobel, D. F., Simon-Miller, A. A., Bézard, B., & Flasar, F. M.
- Affiliations
- Centre National de la Recherche Scientifique (FR)
- Johns Hopkins University (US)
- Goddard Space Flight Center (US)
- Corresponding author
- Fouchet, T.
- Venue
- Nature
- Published
- 2008-05
- Volume
- 453
- Issue
- 7192
- Pages
- 200-202
- ISSN
- 0028-0836 (ISSN-L)
- 1476-4687
- OpenAlex
- W2043249054
- Cited by
- 115
- References
- 25
- Citations by year
- 2026: 3 · 2025: 2 · 2024: 5 · 2023: 3 · 2022: 6 · 2021: 5 · 2020: 11 · 2019: 5 · 2018: 12 · 2017: 4 · 2016: 5 · 2015: 13 · 2014: 4 · 2013: 7 · 2012: 3
- FWCI
- 5.25
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- www.springer.com/tdm (tdm)
- Locations
- Nature (publishedVersion)
- PubMed (publishedVersion)
- HAL (submittedVersion)
- RePEc: Research Papers in Economics (submittedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astro and Planetary Science
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Ionosphere and magnetosphere dynamics
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Atmospheric Ozone and Climate
- Keywords
- Saturn, middle atmosphere, stratosphere, vertically propagating waves, semiannual oscillation, seasonal forcing, superrotation, planetary atmospheres, infrared observations
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review