Articoli di riviste: "Atmospheric tides"

1

Palumbo, A. "Atmospheric tides". Journal of Atmospheric and Solar-Terrestrial Physics 60, n. 3 (febbraio 1998): 279–87. http://dx.doi.org/10.1016/s1364-6826(97)00078-3.

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2

Auclair-Desrotour, P., S. Mathis e J. Laskar. "Atmospheric thermal tides and planetary spin". Astronomy & Astrophysics 609 (gennaio 2018): A118. http://dx.doi.org/10.1051/0004-6361/201731540.

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Context. Thermal atmospheric tides can torque telluric planets away from spin-orbit synchronous rotation, as observed in the case of Venus. They thus participate in determining the possible climates and general circulations of the atmospheres of these planets. Aims. The thermal tidal torque exerted on an atmosphere depends on its internal structure and rotation and on the tidal frequency. Particularly, it strongly varies with the convective stability of the entropy stratification. This dependence has to be characterized to constrain and predict the rotational properties of observed telluric exoplanets. Moreover, it is necessary to validate the approximations used in global modelings such as the traditional approximation, which is used to obtain separable solutions for tidal waves. Methods. We wrote the equations governing the dynamics of thermal tides in a local vertically stratified section of a rotating planetary atmosphere by taking into account the effects of the complete Coriolis acceleration on tidal waves. This allowed us to analytically derive the tidal torque and the tidally dissipated energy, which we used to discuss the possible regimes of tidal dissipation and to examine the key role played by stratification. Results. In agreement with early studies, we find that the frequency dependence of the thermal atmospheric tidal torque in the vicinity of synchronization can be approximated by a Maxwell model. This behavior corresponds to weakly stably stratified or convective fluid layers, as observed previously. A strong stable stratification allows gravity waves to propagate, and makes the tidal torque negligible. The transition is continuous between these two regimes. The traditional approximation appears to be valid in thin atmospheres and in regimes where the rotation frequency is dominated by the forcing or the buoyancy frequencies. Conclusions. Depending on the stability of their atmospheres with respect to convection, observed exoplanets can be tidally driven toward synchronous or asynchronous final rotation rates. The domain of applicability of the traditional approximation is rigorously constrained by calculations.

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Auclair-Desrotour, P., J. Laskar e S. Mathis. "Atmospheric tides in Earth-like planets". Astronomy & Astrophysics 603 (luglio 2017): A107. http://dx.doi.org/10.1051/0004-6361/201628252.

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Context. Atmospheric tides can strongly affect the rotational dynamics of planets. In the family of Earth-like planets, which includes Venus, this physical mechanism coupled with solid tides makes the angular velocity evolve over long timescales and determines the equilibrium configurations of their spin. Aims. Unlike the solid core, the atmosphere of a planet is subject to both tidal gravitational potential and insolation flux coming from the star. The complex response of the gas is intrinsically linked to its physical properties. This dependence has to be characterized and quantified for application to the wide variety of extrasolar planetary systems. Methods. We develop a theoretical global model where radiative losses, which are predominant in slowly rotating atmospheres, are taken into account. We analytically compute the perturbation of pressure, density, temperature, and velocity field caused by a thermogravitational tidal perturbation. From these quantities, we deduce the expressions of atmospheric Love numbers and tidal torque exerted on the fluid shell by the star. The equations are written for the general case of a thick envelope and the simplified one of a thin isothermal atmosphere. Results. The dynamics of atmospheric tides depends on the frequency regime of the tidal perturbation: the thermal regime near synchronization and the dynamical regime characterizing fast-rotating planets. Gravitational and thermal perturbations imply different responses of the fluid, i.e. gravitational tides and thermal tides, which are clearly identified. The dependence of the torque on the tidal frequency is quantified using the analytic expressions of the model for Earth-like and Venus-like exoplanets and is in good agreement with the results given by global climate models (GCM) simulations.Introducing dissipative processes such as radiation regularizes the tidal response of the atmosphere, otherwise it is singular at synchronization. Conclusions. We demonstrate the important role played by the physical and dynamical properties of a super-Earth atmosphere (e.g. Coriolis, stratification, basic pressure, density, temperature, radiative emission) in its response to a tidal perturbation. We point out the key parameters defining tidal regimes (e.g. inertia, Brunt-Väisälä, radiative frequencies, tidal frequency) and characterize the behaviour of the fluid shell in the dissipative regime, which cannot be studied without considering the radiative losses.

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Navarro, Thomas, Timothy M. Merlis, Nicolas B. Cowan e Natalya Gomez. "Atmospheric Gravitational Tides of Earth-like Planets Orbiting Low-mass Stars". Planetary Science Journal 3, n. 7 (1 luglio 2022): 162. http://dx.doi.org/10.3847/psj/ac76cd.

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Abstract Temperate terrestrial planets orbiting low-mass stars are subject to strong tidal forces. The effects of gravitational tides on the solid planet and that of atmospheric thermal tides have been studied, but the direct impact of gravitational tides on the atmosphere itself has so far been ignored. We first develop a simplified analytic theory of tides acting on the atmosphere of a planet. We then implement gravitational tides into a general circulation model of a static-ocean planet in a short-period orbit around a low-mass star—the results agree with our analytic theory. Because atmospheric tides and solid-body tides share a scaling with the semimajor axis, we show that there is a maximum amplitude of the atmospheric tide that a terrestrial planet can experience while still having a solid surface; Proxima Centauri b is the poster child for a planet that could be geophysically Earth-like but with atmospheric tides more than 500× stronger than Earth’s. In this most extreme scenario, we show that atmospheric tides significantly impact the planet’s meteorology—but not its climate. Two possible modest climate impacts are enhanced longitudinal heat transport and cooling of the lowest atmospheric layers. The strong radiative forcing of such planets dominates over gravitational tides, unlike moons of cold giant planets, such as Titan. We speculate that atmospheric tides could be climatologically important on planets where the altitude of maximal tidal forcing coincides with the altitude of cloud formation and that the effect could be detectable for non-Earth-like planets subject to even greater tides.

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Auclair-Desrotour, P., J. Laskar e S. Mathis. "Atmospheric tides and their consequences on the rotational dynamics of terrestrial planets". EAS Publications Series 82 (2019): 81–90. http://dx.doi.org/10.1051/eas/1982008.

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Atmospheric tides can have a strong impact on the rotational dynamics of planets. They are of most importance for terrestrial planets located in the habitable zone of their host star, where their competition with solid tides is likely to drive the body towards non-synchronized rotation states of equilibrium, as observed in the case of Venus. Contrary to other planetary layers, the atmosphere is sensitive to both gravitational and thermal forcings, through a complex dynamical coupling involving the effects of Coriolis acceleration and characteristics of the atmospheric structure. These key physics are usually not taken into account in modelings used to compute the evolution of planetary systems, where tides are described with parametrised prescriptions. In this work, we present a new ab initio modeling of atmospheric tides adapting the theory of the Earth’s atmospheric tides (Chapman & Lindzen 1970) to other terrestrial planets. We derive analytic expressions of the tidal torque, as a function of the tidal frequency and parameters characterizing the internal structure (e.g. the Brunt-Väisälä frequency, the radiative frequency, the pressure heigh scale). We show that stratification plays a key role, the tidal torque being strong in the case of convective atmospheres (i.e. with a neutral stratification) and weak in case of atmosphere convectively stable. In a second step, the model is used to determine the non-synchronized rotation states of equilibrium of Venus-like planets as functions of the physical parameters of the system. These results are detailed in Auclair-Desrotour et al. (2016a) and Auclair-Desrotour et al. (2016b).

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6

Brahde, R. "Lunisolar Atmospheric Tides. II". Australian Journal of Physics 42, n. 4 (1989): 439. http://dx.doi.org/10.1071/ph890439.

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In an earlier paper (Brahde 1988) it was shown that series of measurements of the atmospheric pressure in Oslo contained information about a one�day oscillation with mean amplitude 0�17 mb. The data consisted of measurements every second hour during the years 1957-67, 1969 and 1977. In the present paper the intervening years plus 1978 and 1979 have been included, increasing the basis from 13 to 23 years. In addition the phase shift occurring when the Moon crosses the celestial equator has been defined precisely, thus making it possible to include all the data.

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Brahde, R. "Lunisolar Atmospheric Tides. III". Australian Journal of Physics 44, n. 1 (1991): 87. http://dx.doi.org/10.1071/ph910087.

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In two earlier papers (Brahde 1988, 1989) the atmospheric tide in Oslo (Norway) was studied using pressure data for 23 continuous years. In the present paper a similar study based on pressure data from Batavia (now Jakarta in Indonesia, latitude 6�08'S, longitude 106�45'E) is presented. The result is that the tidal wave caused by the lunisolar tide is represented by a one-day and a half-day oscillation with mean amplitudes of 0 �11 and 0�33 mb respectively. The amplitude spectrum reveals amplitudes of up to 1 mb of dynamiC origin. The 'thermal' tide is also studied and the connection between the thermal and dynamic effects is discussed.

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8

FORBES, Jeffrey M. "Middle Atmosphere Tides and Coupling between Atmospheric Regions". Journal of geomagnetism and geoelectricity 43, Supplement2 (1991): 597–609. http://dx.doi.org/10.5636/jgg.43.supplement2_597.

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9

Salazar, Andrea M., e Robin Wordsworth. "The Feasibility of Asynchronous Rotation via Thermal Tides for Diverse Atmospheric Compositions". Planetary Science Journal 5, n. 10 (1 ottobre 2024): 218. http://dx.doi.org/10.3847/psj/ad74ef.

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Abstract The equilibrium rotation rate of a planet is determined by the sum of torques acting on its solid body. For planets with atmospheres, the dominant torques are usually the gravitational tide, which acts to slow the planet’s rotation rate, and the atmospheric thermal tide, which acts to spin up the planet. Previous work demonstrated that rocky planets with thick atmospheres may produce strong enough thermal tides to avoid tidal locking, but a study of how the strength of the thermal tide depends on atmospheric properties has not been done. In this work, we use a combination of simulations from a global climate model and analytic theory to explore how the thermal tide depends on the shortwave and longwave optical depth of the atmosphere, the surface pressure, and the absorbed stellar radiation. We find that for planets in the habitable zones of M stars only high-pressure but low-opacity atmospheres permit asynchronous rotation owing to the weakening of the thermal tide at high longwave and shortwave optical depths. We conclude that asynchronous rotation may be very unlikely around low-mass stars, which may limit the potential habitability of planets around M stars.

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10

Biagi, P. F., R. Piccolo, V. Capozzi, A. Ermini, S. Martellucci e C. Bellecci. "Exalting in atmospheric tides as earthquake precursor". Natural Hazards and Earth System Sciences 3, n. 3/4 (31 agosto 2003): 197–201. http://dx.doi.org/10.5194/nhess-3-197-2003.

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Abstract. During February–March 1998, we observed a significant increase (6–8 dB) in the electric field of the CZE (f = 270 kHz, Czech Republic) broadcasting station at a site named AS and located in central Italy. On 13 March 1998 an earthquake (M = 5.2) occurred in Slovenia, starting a strong seismic crisis (M = 6.0 on 12 April, M = 5.1 on 6 May). The distances of the epicentres from the radio receiver were over 400 km, but the epicentres are located in a zone that is in the middle of the CZE-AS path. Previously, we advanced the hypothesis that the increase of radio-signal electric field detected could be a precursor of the Slovenia seismic crisis. At the purpose to precise the connection between this radio anomaly and the preparatory phase of the earthquakes, we analysed in detail the data collected. At first we carried out a FFT on the data and clear harmonic components with period 0.5d, 1d, 14d, 28d and 365d were revealed. These periods are characteristic of gravity tides and therefore, it seems reasonable to consider the previous harmonics in the electric field of the radio signal as components related to tides of the atmosphere, assuming as tides of the atmosphere only the linear action of gravity tides on atmosphere. Then, we carried out band pass filters on our data and we discovered that the February–March 1998 increase is mainly related to an exalting of the harmonics with period 0.5d, 1d, 14d and 28d, i.e. of the (semi)monthly and (semi)diurnal atmospheric tidal components in the radio signal. Supposing that this exalting is produced by a corresponding exalting of the atmospheric tides we propose a model able to explain the production of such an effect during the preparatory phase of the Slovenia earthquakes.

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11

Forbes, Jeffrey M., e Gerald V. Groves. "Atmospheric tides below 80 km". Advances in Space Research 10, n. 12 (gennaio 1990): 119–25. http://dx.doi.org/10.1016/0273-1177(90)90391-c.

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12

Cunha, Diana, Alexandre C. M. Correia e Jacques Laskar. "Spin evolution of Earth-sized exoplanets, including atmospheric tides and core–mantle friction". International Journal of Astrobiology 14, n. 2 (30 luglio 2014): 233–54. http://dx.doi.org/10.1017/s1473550414000226.

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AbstractPlanets with masses between 0.1 and 10 M⊕ are believed to host dense atmospheres. These atmospheres can play an important role on the planet's spin evolution, since thermal atmospheric tides, driven by the host star, may counterbalance gravitational tides. In this work, we study the long-term spin evolution of Earth-sized exoplanets. We generalize previous works by including the effect of eccentric orbits and obliquity. We show that under the effect of tides and core–mantle friction, the obliquity of the planets evolves either to 0° or 180°. The rotation of these planets is also expected to evolve into a very restricted number of equilibrium configurations. In general, none of these equilibria is synchronous with the orbital mean motion. The role of thermal atmospheric tides becomes more important for Earth-sized planets in the habitable zones of their systems; so they cannot be neglected when we search for their potential habitability.

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13

Hagen, Jonas, Klemens Hocke, Gunter Stober, Simon Pfreundschuh, Axel Murk e Niklaus Kämpfer. "First measurements of tides in the stratosphere and lower mesosphere by ground-based Doppler microwave wind radiometry". Atmospheric Chemistry and Physics 20, n. 4 (28 febbraio 2020): 2367–86. http://dx.doi.org/10.5194/acp-20-2367-2020.

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Abstract. Atmospheric tides are important for vertical coupling in the atmosphere, from the stratosphere down to the troposphere and up to the thermosphere. They are planetary-scale gravity waves with well-known periods that are integer fractions of a day and can be observed in the temperature or wind fields in the atmosphere. Most lidar techniques and satellites measure atmospheric tides only in the temperature field and continuous measurements of the tides in the wind field of the stratosphere and lower mesosphere are rare, even though, with modern lidars, they would be feasible. In this study, we present measurements of the diurnal tide in the wind field in the stratosphere and lower mesosphere by ground-based microwave wind radiometry for two different campaigns in tropical and polar regions. Further, we compare our measurements to MERRA-2 reanalysis data. In the tri-monthly mean, we find a good correspondence in the amplitude and phase of the diurnal tide between measurements and reanalysis with the most important features of the diurnal tides represented in both data sets. When looking at shorter timescales, we find significant differences in the data sets. We make an attempt to examine these differences and discriminate between atmospheric variability and noise, and we present some hints for intermittent diurnal tides. We conclude that continuous ground-based observations of tides in the middle atmospheric wind field are feasible, and they deliver consistent results for the mean amplitude and phase of the diurnal tide in the tri-monthly mean. We further discuss the limitations in regards to short timescale observations of tides and the possibility to provide additional insight into middle atmospheric dynamics that is complementary to temperature observations and reanalysis data.

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Krochin, Witali, Axel Murk e Gunter Stober. "Thermal tides in the middle atmosphere at mid-latitudes measured with a ground-based microwave radiometer". Atmospheric Measurement Techniques 17, n. 17 (3 settembre 2024): 5015–28. http://dx.doi.org/10.5194/amt-17-5015-2024.

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Abstract. In recent decades, theoretical studies and numerical models of thermal tides have gained attention. It has been recognized that tides have a significant influence on the dynamics of the middle and upper atmosphere; as they grow in amplitude and propagate upward, they transport energy and momentum from the lower to the upper atmosphere, contributing to the vertical coupling between atmospheric layers. The superposition of tides with other atmospheric waves leads to non-linear wave–wave interactions. However, direct measurements of thermal tides in the middle atmosphere are challenging and are often limited to satellite measurements in the tropics and at low latitudes. Due to orbit geometry, such observations provide only a reduced insight into the short-term variability in atmospheric tides. In this paper, we present tidal analysis from 5 years of continuous observations of middle-atmospheric temperatures. The measurements were performed with the ground-based temperature radiometer TEMPERA (TEMPErature RAdiometer), which was developed at the University of Bern in 2013 and was located in Bern (46.95° N, 7.45° E) and Payerne (46.82° N, 6.94° E). TEMPERA achieves a temporal resolution of 1–3 h and covers the altitude range between 25–50 km. Using an adaptive spectral filter with a vertical regularization (ASF2D) for the tidal analysis, we found maximum amplitudes for the diurnal tide of approximately 2.4 K, accompanied by seasonal variability. The maximum amplitude was reached on average at an altitude of 43 km, which also reflected some seasonal characteristics. We demonstrate that TEMPERA is suitable for providing continuous temperature soundings in the stratosphere and lower mesosphere with a sufficient cadence to infer tidal amplitudes and phases for the dominating tidal modes. Furthermore, our measurements exhibit a dominating diurnal tide and smaller amplitudes for the semidiurnal and terdiurnal tides in the stratosphere.

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Lindzen, Richard S. "Richard J. Reed and Atmospheric Tides". Meteorological Monographs 53 (1 dicembre 2003): 85–89. http://dx.doi.org/10.1175/0065-9401-31.53.85.

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16

Palumbo, A. "Reply to comments on "Atmospheric Tides"". Journal of Atmospheric and Solar-Terrestrial Physics 60, n. 18 (dicembre 1998): 1793. http://dx.doi.org/10.1016/s1364-6826(98)00148-5.

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Price, Colin, Ron Maor e Hofit Shachaf. "Using smartphones for monitoring atmospheric tides". Journal of Atmospheric and Solar-Terrestrial Physics 174 (settembre 2018): 1–4. http://dx.doi.org/10.1016/j.jastp.2018.04.015.

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18

Brahde, R. "Lunisolar Atmospheric Tides: A New Approach". Australian Journal of Physics 41, n. 6 (1988): 807. http://dx.doi.org/10.1071/ph880807.

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In records of the atmospheric pressure in Oslo, at 60' latitude, a one-day oscillation caused by the lunisolar tide has been detected. The amplitude has a mean value of O� 17 mb. This oscillation appears during intervals when the declination of the Moon has high numerical values. When the Moon passes through the equator, the one-day oscillation disappears and only the half-day mode continues. If a maximum coincides with upper culmination, it reappears during the next fortnight at lower culmination. This means that the phase changes approximately 180' or 12h every time the Moon crosses the equator, and this is the main reason why it has not been detected by means of traditional harmonic analysis of the atmospheric pressure oscillations. By means of the correlation between the pressure variation and the magnitude of the tidal acceleration, it was possible to separate the dynamic one-day oscillation from terms of thermal origin.

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French, Richard G., Anthony D. Toigo, Peter J. Gierasch, Candice J. Hansen, Leslie A. Young, Bruno Sicardy, Alex Dias-Oliveira e Scott D. Guzewich. "Seasonal variations in Pluto’s atmospheric tides". Icarus 246 (gennaio 2015): 247–67. http://dx.doi.org/10.1016/j.icarus.2014.05.017.

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20

Guzewich, Scott D., C. E. Newman, M. de la Torre Juárez, R. J. Wilson, M. Lemmon, M. D. Smith, H. Kahanpää e A. M. Harri. "Atmospheric tides in Gale Crater, Mars". Icarus 268 (aprile 2016): 37–49. http://dx.doi.org/10.1016/j.icarus.2015.12.028.

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21

Wergen, W. "Normal mode initialization and atmospheric tides". Quarterly Journal of the Royal Meteorological Society 115, n. 487 (aprile 1989): 535–45. http://dx.doi.org/10.1002/qj.49711548706.

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22

Hupe, Patrick, Lars Ceranna e Christoph Pilger. "Using barometric time series of the IMS infrasound network for a global analysis of thermally induced atmospheric tides". Atmospheric Measurement Techniques 11, n. 4 (10 aprile 2018): 2027–40. http://dx.doi.org/10.5194/amt-11-2027-2018.

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Abstract. The International Monitoring System (IMS) has been established to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty and comprises four technologies, one of which is infrasound. When fully established, the IMS infrasound network consists of 60 sites uniformly distributed around the globe. Besides its primary purpose of determining explosions in the atmosphere, the recorded data reveal information on other anthropogenic and natural infrasound sources. Furthermore, the almost continuous multi-year recordings of differential and absolute air pressure allow for analysing the atmospheric conditions. In this paper, spectral analysis tools are applied to derive atmospheric dynamics from barometric time series. Based on the solar atmospheric tides, a methodology for performing geographic and temporal variability analyses is presented, which is supposed to serve for upcoming studies related to atmospheric dynamics. The surplus value of using the IMS infrasound network data for such purposes is demonstrated by comparing the findings on the thermal tides with previous studies and the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2), which represents the solar tides well in its surface pressure fields. Absolute air pressure recordings reveal geographical characteristics of atmospheric tides related to the solar day and even to the lunar day. We therefore claim the chosen methodology of using the IMS infrasound network to be applicable for global and temporal studies on specific atmospheric dynamics. Given the accuracy and high temporal resolution of the barometric data from the IMS infrasound network, interactions with gravity waves and planetary waves can be examined in future for refining the knowledge of atmospheric dynamics, e.g. the origin of tidal harmonics up to 9 cycles per day as found in the barometric data sets. Data assimilation in empirical models of solar tides would be a valuable application of the IMS infrasound data.

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23

Tokioka, Tatsushi, e Isamu Yagai. "Atmospheric Tides Appearing in a Global Atmospheric General Circulation Model". Journal of the Meteorological Society of Japan. Ser. II 65, n. 3 (1987): 423–38. http://dx.doi.org/10.2151/jmsj1965.65.3_423.

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Covey, Curt, Aiguo Dai, Dan Marsh e Richard S. Lindzen. "The Surface-Pressure Signature of Atmospheric Tides in Modern Climate Models". Journal of the Atmospheric Sciences 68, n. 3 (1 marzo 2011): 495–514. http://dx.doi.org/10.1175/2010jas3560.1.

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Abstract Although atmospheric tides driven by solar heating are readily detectable at the earth’s surface as variations in air pressure, their simulations in current coupled global climate models have not been fully examined. This work examines near-surface-pressure tides in climate models that contributed to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC); it compares them with tides both from observations and from the Whole Atmosphere Community Climate Model (WACCM), which extends from the earth’s surface to the thermosphere. Surprising consistency is found among observations and all model simulations, despite variation of the altitudes of model upper boundaries from 32 to 76 km in the IPCC models and at 135 km for WACCM. These results are consistent with previous suggestions that placing a model’s upper boundary at low altitude leads to partly compensating errors—such as reducing the forcing of the tides by ozone heating, but also introducing spurious waves at the upper boundary, which propagate to the surface.

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Charnay, B., G. Tobie, S. Lebonnois e R. D. Lorenz. "Gravitational atmospheric tides as a probe of Titan’s interior: Application to Dragonfly". Astronomy & Astrophysics 658 (febbraio 2022): A108. http://dx.doi.org/10.1051/0004-6361/202141898.

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Context. Saturn’s massive gravity is expected to causes a tide in Titan’s atmosphere, producing a surface pressure variation through the orbit of Titan and tidal winds in the troposphere. The future Dragonfly mission could analyse this exotic meteorological phenomenon. Aims. We aim to analyse the effect of Saturn’s tides on Titan’s atmosphere and interior to determine how pressure measurements by Dragonfly could constrain Titan’s interior. Methods. We model atmospheric tides with analytical calculations and with a 3D global climate model (the IPSL-Titan GCM), including the tidal response of the interior. Results. We predict that the Love numbers of Titan’s interior should verify 1 + ℜ(k2 − h2) ~ 0.02–0.1 and ℑ(k2 − h2) < 0.04. The deformation of Titan’s interior should therefore strongly weaken gravitational atmospheric tides, yielding a residual surface pressure amplitude of only ~5 Pa, with a phase shift of 5–20 h. Tidal winds are very weak, of the order of 3 × 10−4 m s−1 in the lower troposphere. Finally, constraints from Dragonfly data may permit the real and the imaginary parts of k2 − h2 to be estimated with a precision of ±0.01–0.03. Conclusions. Measurements of pressure variations by Dragonfly over the whole mission could give valuable constraints on the thickness of Titan’s ice shell, and, via geophysical models, its heat flux and the density of its internal ocean.

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Braswell, William D., e Richard S. Lindzen. "Anomalous short wave absorption and atmospheric tides". Geophysical Research Letters 25, n. 9 (1 maggio 1998): 1293–96. http://dx.doi.org/10.1029/98gl01031.

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Andruk, V., G. Butenko, V. Kostyuchenko e L. Svachij. "The relation between extinction and atmospheric tides". Journal of Physical Studies 11, n. 4 (2007): 432–37. http://dx.doi.org/10.30970/jps.11.432.

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Arabelos, D., G. Asteriadis, M. E. Contadakis, S. D. Spatalas e H. Sachsamanoglou. "Atmospheric tides in the area of Thessaloniki". Journal of Geodynamics 23, n. 1 (gennaio 1997): 65–75. http://dx.doi.org/10.1016/s0264-3707(96)00018-x.

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Zharov, V. E., e D. Gambis. "Atmospheric tides and rotation of the Earth". Journal of Geodesy 70, n. 6 (giugno 1996): 321–26. http://dx.doi.org/10.1007/bf00868183.

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Zharov, V. E., e D. Gambis. "Atmospheric tides and rotation of the Earth". Journal of Geodesy 70, n. 6 (1 marzo 1996): 321–26. http://dx.doi.org/10.1007/s001900050022.

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Balcerak, Ernie. "Atmospheric tides link stratosphere and ionosphere changes". Eos, Transactions American Geophysical Union 95, n. 24 (17 giugno 2014): 208. http://dx.doi.org/10.1002/2014eo240008.

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Griffith, Matthew J., e Nicholas J. Mitchell. "Analysis of migrating and non-migrating tides of the Extended Unified Model in the mesosphere and lower thermosphere". Annales Geophysicae 40, n. 3 (1 giugno 2022): 327–58. http://dx.doi.org/10.5194/angeo-40-327-2022.

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Abstract. Atmospheric tides play a key role in coupling the lower, middle, and upper atmosphere/ionosphere. The tides reach large amplitudes in the mesosphere and lower thermosphere (MLT), where they can have significant fluxes of energy and momentum, and so strongly influence the coupling and dynamics. The tides must therefore be accurately represented in general circulation models (GCMs) that seek to model the coupling of atmospheric layers and impacts on the ionosphere. The tides consist of both migrating (sun-following) and non-migrating (not sun-following) components, both of which have important influences on the atmosphere. The Extended Unified Model (ExUM) is a recently developed version of the Met Office's GCM (the Unified Model) which has been extended to include the MLT. Here, we present the first in-depth analysis of migrating and non-migrating components in the ExUM. We show that the ExUM produces both non-migrating and migrating tides in the MLT of significant amplitude across a rich spectrum of spatial and temporal components. The dominant non-migrating components in the MLT are found to be DE3, DW2, and DW3 in the diurnal tide and S0, SW1, and SW3 in the semidiurnal tide. These components in the model can have monthly mean amplitudes at a height of 95 km as large as 35 m s−1/10 K. All the non-migrating components exhibit a strong seasonal variability in amplitude, and a significant short-term variability is evident. Both the migrating and non-migrating components exhibit notable variation with latitude. For example, the temperature and wind diurnal tides maximise at low latitudes and the semidiurnal tides include maxima at high latitudes. A comparison against published satellite and ground-based observations shows generally good agreement in latitudinal tidal structure, with more differences in seasonal tidal structure. Our results demonstrate the capability of the ExUM for modelling atmospheric migrating and non-migrating tides, and this lays the foundation for its future development into a whole atmosphere model. To this end, we make specific recommendations on further developments which would improve the capability of the model.

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33

Covey, Curt, Aiguo Dai, Richard S. Lindzen e Daniel R. Marsh. "Atmospheric Tides in the Latest Generation of Climate Models*". Journal of the Atmospheric Sciences 71, n. 6 (30 maggio 2014): 1905–13. http://dx.doi.org/10.1175/jas-d-13-0358.1.

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Abstract For atmospheric tides driven by solar heating, the database of climate model output used in the most recent assessment report of the Intergovernmental Panel on Climate Change (IPCC) confirms and extends the authors’ earlier results based on the previous generation of models. Both the present study and the earlier one examine the surface pressure signature of the tides, but the new database removes a shortcoming of the earlier study in which model simulations were not strictly comparable to observations. The present study confirms an approximate consistency among observations and all model simulations, despite variation of model tops from 31 to 144 km. On its face, this result is surprising because the dominant (semidiurnal) component of the tides is forced mostly by ozone heating around 30–70-km altitude. Classical linear tide calculations and occasional numerical experimentation have long suggested that models with low tops achieve some consistency with observations by means of compensating errors, with wave reflection from the model top making up for reduced ozone forcing. Future work with the new database may confirm this hypothesis by additional classical calculations and analyses of the ozone heating profiles and wave reflection in Coupled Model Intercomparison Project (CMIP) models. The new generation of models also extends CMIP's purview to free-atmosphere fields including the middle atmosphere and above.

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34

Williams, Joanne, Maialen Irazoqui Apecechea, Andrew Saulter e Kevin J. Horsburgh. "Radiational tides: their double-counting in storm surge forecasts and contribution to the Highest Astronomical Tide". Ocean Science 14, n. 5 (14 settembre 2018): 1057–68. http://dx.doi.org/10.5194/os-14-1057-2018.

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Abstract. Tide predictions based on tide-gauge observations are not just the astronomical tides; they also contain radiational tides – periodic sea-level changes due to atmospheric conditions and solar forcing. This poses a problem of double-counting for operational forecasts of total water level during storm surges. In some surge forecasting, a regional model is run in two modes: tide only, with astronomic forcing alone; and tide and surge, forced additionally by surface winds and pressure. The surge residual is defined to be the difference between these configurations and is added to the local harmonic predictions from gauges. Here we use the Global Tide and Surge Model (GTSM) based on Delft-FM to investigate this in the UK and elsewhere, quantifying the weather-related tides that may be double-counted in operational forecasts. We show that the global S2 atmospheric tide is captured by the tide-and-surge model and observe changes in other major constituents, including M2. The Lowest and Highest Astronomical Tide levels, used in navigation datums and design heights, are derived from tide predictions based on observations. We use our findings on radiational tides to quantify the extent to which these levels may contain weather-related components.

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35

Harris, M. J., N. F. Arnold e A. D. Aylward. "A study into the effect of the diurnal tide on the structure of the background mesosphere and thermosphere using the new coupled middle atmosphere and thermosphere (CMAT) general circulation model". Annales Geophysicae 20, n. 2 (28 febbraio 2002): 225–35. http://dx.doi.org/10.5194/angeo-20-225-2002.

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Abstract. A new coupled middle atmosphere and thermosphere general circulation model has been developed, and some first results are presented. An investigation into the effects of the diurnal tide upon the mean composition, dynamics and energetics was carried out for equinox conditions. Previous studies have shown that tides deplete mean atomic oxygen in the upper mesosphere-lower thermosphere due to an increased recombination in the tidal displaced air parcels. The model runs presented suggest that the mean residual circulation associated with the tidal dissipation also plays an important role. Stronger lower boundary tidal forcing was seen to increase the equatorial local diurnal maximum of atomic oxygen and the associated 0(1S) 557.7 nm green line volume emission rates. The changes in the mean background temperature structure were found to correspond to changes in the mean circulation and exothermic chemical heating.Key words. Atmospheric composition and structure (middle atmosphere – composition and chemistry) Meterology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)

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36

Shved, G. M., L. N. Petrova e O. S. Polyakova. "Penetration of the Earth's free oscillations at 54 minute period into the atmosphere". Annales Geophysicae 18, n. 5 (31 maggio 2000): 566–72. http://dx.doi.org/10.1007/s00585-000-0566-0.

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Abstract. It is known that the fundamental spheroidal mode 0S2 of the Earth free oscillation with a period of about 54 min forces atmospheric oscillations. We present a certain phase relationship for components of the 0S2 multiplet, which is based on synchronous collocated microbarograph and seismograph observations. This relationship is both the first observational manifestation of the Pekeris mode of global atmospheric oscillations with the 54 min period and a further proof of the Earth's 0S2 mode penetrating into the atmosphere. We show that the linear non-dissipative model of steady forced oscillations in isothermal atmosphere at rest does not describe the penetration of the 0S2 mode into the atmosphere adequately.Key words: Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)

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37

Pan, Q. W., J. E. Allnutt e C. Tsui. "Evidence of atmospheric tides from satellite beacon experiment". Electronics Letters 42, n. 12 (2006): 706. http://dx.doi.org/10.1049/el:20060408.

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38

Vial, François. "Numerical simulations of atmospheric tides for solstice conditions". Journal of Geophysical Research 91, A8 (1986): 8955. http://dx.doi.org/10.1029/ja091ia08p08955.

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39

Forbes, Jeffrey M. "Atmospheric tides between 80 km and 120 km". Advances in Space Research 10, n. 12 (gennaio 1990): 127–40. http://dx.doi.org/10.1016/0273-1177(90)90392-d.

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40

Bartzokas, A., C. C. Repapis e D. A. Metaxas. "Temporal variations of atmospheric tides over Athens, Greece". Meteorology and Atmospheric Physics 55, n. 1-2 (1995): 113–23. http://dx.doi.org/10.1007/bf01029606.

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41

Bills, Bruce G., Thomas Navarro, Gerald Schubert, Anton Ermakov e Krzysztof M. Górski. "Gravitational signatures of atmospheric thermal tides on Venus". Icarus 340 (aprile 2020): 113568. http://dx.doi.org/10.1016/j.icarus.2019.113568.

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42

Palus, Shannon. "Role of lunar atmospheric tides in thermosphere density". Eos, Transactions American Geophysical Union 95, n. 47 (25 novembre 2014): 444. http://dx.doi.org/10.1002/2014eo470012.

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43

REDDY, S. JEEV ANANDA. "Lunar and solar atmospheric tides in surface winds and rainfall". MAUSAM 25, n. 3 (21 febbraio 2022): 499–502. http://dx.doi.org/10.54302/mausam.v25i3.5264.

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Lunar and solar atmospheric tides in surface winds and rainfall data at 4 stations have been determined following Chapman-Miller method as detailed by Malin and Chapman. Using the similar results obtained by Rao and Reddy (1972) for other stations a synthesis of the lunar and solar tides in surface winds and rainfall data for Indian stations have been made.

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44

Griffith, Matthew J., Shaun M. Dempsey, David R. Jackson, Tracy Moffat-Griffin e Nicholas J. Mitchell. "Winds and tides of the Extended Unified Model in the mesosphere and lower thermosphere validated with meteor radar observations". Annales Geophysicae 39, n. 3 (10 giugno 2021): 487–514. http://dx.doi.org/10.5194/angeo-39-487-2021.

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Abstract. The mesosphere and lower thermosphere (MLT) is a critical region that must be accurately reproduced in general circulation models (GCMs) that aim to include the coupling between the lower and middle atmosphere and the thermosphere. An accurate representation of the MLT is thus important for improved climate modelling and the development of a whole atmosphere model. This is because the atmospheric waves at these heights are particularly large, and so the energy and momentum they carry is an important driver of climatological phenomena through the whole atmosphere, affecting terrestrial and space weather. The Extended Unified Model (ExUM) is the recently developed version of the Met Office's Unified Model which has been extended to model the MLT. The capability of the ExUM to model atmospheric winds and tides in the MLT is currently unknown. Here, we present the first study of winds and tides from the ExUM. We make a comparison against meteor radar observations of winds and tides from 2006 between 80 and 100 km over two radar stations – Rothera (68∘ S, 68∘ W) and Ascension Island (8∘ S, 14∘ W). These locations are chosen to study tides in two very different tidal regimes – the equatorial regime, where the diurnal (24 h) tide dominates, and the polar regime, where the semi-diurnal (12 h) tide dominates. The results of this study illustrate that the ExUM is capable of reproducing atmospheric winds and tides that capture many of the key characteristics seen in meteor radar observations, such as zonal and meridional wind maxima and minima, the increase in tidal amplitude with increasing height, and the decrease in tidal phase with increasing height. In particular, in the equatorial regime some essential characteristics of the background winds, tidal amplitudes and tidal phases are well captured but with significant differences in detail. In the polar regime, the difference is more pronounced. The ExUM zonal background winds in austral winter are primarily westward rather than eastward, and in austral summer they are larger than observed above 90 km. The ExUM tidal amplitudes here are in general consistent with observed values, but they are also larger than observed values above 90 km in austral summer. The tidal phases are generally well replicated in this regime. We propose that the bias in background winds in the polar regime is a consequence of the lack of in situ gravity wave generation to generate eastward fluxes in the MLT. The results of this study indicate that the ExUM has a good natural capability for modelling atmospheric winds and tides in the MLT but that there is room for improvement in the model physics in this region. This highlights the need for modifications to the physical parameterization schemes used in the model in this region – such as the non-orographic spectral gravity wave scheme – to improve aspects such as polar circulation. To this end, we make specific recommendations of changes that can be implemented to improve the accuracy of the ExUM in the MLT.

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45

Volland, Hans. "Comments on "Atmosphereic Tides" by A.Palumbo". Journal of Atmospheric and Solar-Terrestrial Physics 60, n. 18 (dicembre 1998): 1791–92. http://dx.doi.org/10.1016/s1364-6826(98)00147-3.

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46

Wilson, Ian R. G., e Nikolay S. Sidorenkov. "Long-Term Lunar Atmospheric Tides in the Southern Hemisphere". Open Atmospheric Science Journal 7, n. 1 (17 maggio 2013): 51–76. http://dx.doi.org/10.2174/1874282320130415001.

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The longitudinal shift-and-add method is used to show that there are N=4 standing wave-like patterns in the summer (DJF) mean sea level pressure (MSLP) and sea-surface temperature (SST) anomaly maps of the Southern Hemisphere between 1947 and 1994. The patterns in the MSLP anomaly maps circumnavigate the Earth in 36, 18, and 9 years. This indicates that they are associated with the long-term lunar atmospheric tides that are either being driven by the 18.0 year Saros cycle or the 18.6 year lunar Draconic cycle. In contrast, the N=4 standing wave-like patterns in the SST anomaly maps circumnavigate the Earth once every 36, 18 and 9 years between 1947 and 1970 but then start circumnavigating the Earth once every 20.6 or 10.3 years between 1971 and 1994. The latter circumnavigation times indicate that they are being driven by the lunar Perigee-Syzygy tidal cycle. It is proposed that the different drift rates for the patterns seen in the MSLP and SST anomaly maps between 1971 and 1994 are the result of a reinforcement of the lunar Draconic cycle by the lunar Perigee-Syzygy cycle at the time of Perihelion. It is claimed that this reinforcement is part of a 31/62/93/186 year lunar tidal cycle that produces variations on time scales of 9.3 and 93 years. Finally, an N=4 standing wave-like pattern in the MSLP that circumnavigates the Southern Hemisphere every 18.6 years will naturally produce large extended regions of abnormal atmospheric pressure passing over the semi-permanent South Pacific subtropical high roughly once every ~ 4.5 years. These moving regions of higher/lower than normal atmospheric pressure will increase/decrease the MSLP of this semi-permanent high pressure system, temporarily increasing/reducing the strength of the East-Pacific trade winds. This may led to conditions that preferentially favor the onset of La Nina/El Nino events.

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47

RAO, K. N., e S. JEEVANANDA REDDY. "Solar and lunar atmospheric tides in rainfall at Poona". MAUSAM 23, n. 4 (7 febbraio 2022): 535–36. http://dx.doi.org/10.54302/mausam.v23i4.5315.

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The atmospheric tides in 'the rainfall data of the monsoon season, ...e., June to September at Poona (18° 32' N; 73° 51'E), have been studied by using hourly mean values and bi-hourly mean values for the period 1949-1960. Both solar and lunar effects upto the 4th harmonic have been discussed. Study of the variation with lunar phase of the rainfall indicates a maximum fall near the phase 3 while there is no other regular variation with lunar phase.

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48

Schulz, William H., Jason W. Kean e Gonghui Wang. "Landslide movement in southwest Colorado triggered by atmospheric tides". Nature Geoscience 2, n. 12 (1 novembre 2009): 863–66. http://dx.doi.org/10.1038/ngeo659.

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49

Sherwood, Steven C. "Climate signal mapping and an application to atmospheric tides". Geophysical Research Letters 27, n. 21 (1 novembre 2000): 3525–28. http://dx.doi.org/10.1029/2000gl011424.

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50

Malinga, Sandile B., e L. M. G. Poole. "Atmospheric tides observed at Grahamstown (33.3 °S, 26.5 °E)". Journal of Atmospheric and Solar-Terrestrial Physics 59, n. 16 (novembre 1997): 2037–50. http://dx.doi.org/10.1016/s1364-6826(97)00044-8.

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