Academic literature on the topic 'Earths atmosphere'

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Journal articles on the topic "Earths atmosphere"

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Miller-Ricci, Eliza, Sara Seager, and Dimitar Sasselov. "The Atmospheres of Extrasolar Super-Earths." Proceedings of the International Astronomical Union 4, S253 (May 2008): 263–71. http://dx.doi.org/10.1017/s1743921308026483.

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AbstractExtrasolar super-Earths (1-10 M⊕) are likely to exist with a wide range of atmospheres. While a number of these planets have already been discovered through radial velocities and microlensing, it will be the discovery of the firsttransitingsuper-Earths that will open the door to a variety of follow-up observations aimed at characterizing their atmospheres. Super-Earths may fill a large range of parameter space in terms of their atmospheric composition and mass. Specifically, some of these planets may have high enough surface gravities to be able to retain large hydrogen-rich atmosphseres, while others will have lost most of their hydrogen to space over the planet's lifetime, leaving behind an atmosphere more closely resembling that of Earth or Venus. The resulting composition of the super-Earth atmosphere will therefore depend strongly on factors such as atmospheric escape history, outgassing history, and the level of stellar irradiation that it receives. Here we present theoretical models of super-Earth emission and transmission spectra for a variety of possible outcomes of super-Earth atmospheric composition ranging from hydrogen-rich to hydrogen-poor. We focus on how observations can be used to differentiate between the various scenarios and constrain atmospheric composition.
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Kempton, Eliza M. R. "The properties of super-Earth atmospheres." Proceedings of the International Astronomical Union 6, S276 (October 2010): 212–17. http://dx.doi.org/10.1017/s1743921311020205.

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AbstractExtrasolar super-Earths likely have a far greater diversity in their atmospheric properties than giant planets. Super-Earths (planets with masses between 1 and 10 M⊕) lie in an intermediate mass regime between gas/ice giants like Neptune and rocky terrestrial planets like Earth and Venus. While some super-Earths (especially the more massive ones) may retain large amounts of hydrogen either from accretion processes or subsequent surface outgassing, other super-Earths should have atmospheres composed of predominantly heavier molecules, similar to the atmospheres of the rocky planets and moons of our Solar System. Others still may be entirely stripped of their atmospheres and remain as bare rocky cores. Of the two currently known transiting super-Earths one (GJ 1214b) likely falls into the former category with a thick atmosphere, while the other (CoRoT-7b) falls into the latter category with a very thin or nonexistent atmosphere. I review some of the theoretical work on super-Earth atmospheres, and I present methods for determining the bulk composition of a super-Earth atmosphere.
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Kimura, Tadahiro, and Masahiro Ikoma. "Formation of aqua planets with water of nebular origin: effects of water enrichment on the structure and mass of captured atmospheres of terrestrial planets." Monthly Notices of the Royal Astronomical Society 496, no. 3 (June 22, 2020): 3755–66. http://dx.doi.org/10.1093/mnras/staa1778.

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ABSTRACT Recent detection of exoplanets with Earth-like insolation attracts growing interest in how common Earth-like aqua planets are beyond the Solar system. While terrestrial planets are often assumed to capture icy or water-rich planetesimals, a primordial atmosphere of nebular origin itself can produce water through oxidation of the atmospheric hydrogen with oxidizing minerals from incoming planetesimals or the magma ocean. Thermodynamically, normal oxygen buffers produce water comparable in mole number equal to or more than hydrogen. Thus, the primordial atmosphere would likely be highly enriched with water vapour; however, the primordial atmospheres have been always assumed to have the solar abundances. Here we integrate the 1D structure of such an enriched atmosphere of sub-Earths embedded in a protoplanetary disc around an M dwarf of 0.3$\, \mathrm{M}_\odot$ and investigate the effects of water enrichment on the atmospheric properties with focus on water amount. We find that the well-mixed highly enriched atmosphere is more massive by a few orders of magnitude than the solar-abundance atmosphere, and that even a Mars-mass planet can obtain water comparable to the present Earth’s oceans. Although close-in Mars-mass planets likely lose the captured water via disc dispersal and photoevaporation, these results suggest that there are more sub-Earths with Earth-like water contents than previously predicted. How much water terrestrial planets really obtain and retain against subsequent loss, however, depends on efficiencies of water production, mixing in the atmosphere and magma ocean, and photoevaporation, detailed investigation for which should be made in the future.
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Madhusudhan, Nikku, and Seth Redfield. "Optimal measures for characterizing water-rich super-Earths." International Journal of Astrobiology 14, no. 2 (October 29, 2014): 177–89. http://dx.doi.org/10.1017/s1473550414000421.

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AbstractThe detection and atmospheric characterization of super-Earths is one of the major frontiers of exoplanetary science. Currently, extensive efforts are underway to detect molecules, particularly H2O, in super-Earth atmospheres. In the present work, we develop a systematic set of strategies to identify and observe potentially H2O-rich super-Earths that provide the best prospects for characterizing their atmospheres using existing instruments. First, we provide analytic prescriptions and discuss factors that need to be taken into account while planning and interpreting observations of super-Earth radii and spectra. We discuss how observations in different spectral bandpasses constrain different atmospheric properties of a super-Earth, including radius and temperature of the planetary surface as well as the mean molecular mass, the chemical composition and thermal profile of the atmosphere. In particular, we caution that radii measured in certain bandpasses can induce biases in the interpretation of the interior compositions. Second, we investigate the detectability of H2O-rich super-Earth atmospheres using the Hubble Space Telescope Wide Field Camera 3 spectrograph as a function of the planetary properties and stellar brightness. We find that highly irradiated super-Earths orbiting bright stars, such as 55 Cancri e, present better candidates for atmospheric characterization compared to cooler planets such as GJ 1214b even if the latter orbit lower-mass stars. Besides being better candidates for both transmission and emission spectroscopy, hotter planets offer higher likelihood of cloud-free atmospheres which aid tremendously in the observation and interpretation of spectra. Finally, we present case studies of two super-Earths, GJ 1214b and 55 Cancri e, using available data and models of their interiors and atmospheres.
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Claudi, R., M. S. Erculiani, G. Galletta, D. Billi, E. Pace, D. Schierano, E. Giro, and M. D'Alessandro. "Simulating super earth atmospheres in the laboratory." International Journal of Astrobiology 15, no. 1 (May 20, 2015): 35–44. http://dx.doi.org/10.1017/s1473550415000117.

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AbstractSeveral space missions, such as JWST, TESS and the very recently proposed ARIEL, or ground-based experiments, as SPHERE and GPI, have been proposed to measure the atmospheric transmission, reflection and emission spectra of extrasolar planets. The planet atmosphere characteristics and possible biosignatures will be inferred by studying planetary spectra in order to identify the emission/absorption lines/bands from atmospheric molecules such as water (H2O), carbon monoxide (CO), methane (CH4), ammonia (NH3), etc. In particular, it is important to know in detail the optical characteristics of gases in the typical physical conditions of the planetary atmospheres and how these characteristics could be affected by radiation driven photochemical and biochemical reaction. The main aim of the project ‘Atmosphere in a Test Tube’ is to provide insights on exoplanet atmosphere modification due to biological intervention. This can be achieved simulating planetary atmosphere at different pressure and temperature conditions under the effects of radiation sources, used as proxies of different bands of the stellar emission. We are tackling the characterization of extrasolar planet atmospheres by mean of innovative laboratory experiments described in this paper. The experiments are intended to reproduce the conditions on warm earths and super earths hosted by low-mass M dwarfs primaries with the aim to understand if a cyanobacteria population hosted on a Earth-like planet orbiting an M0 star is able to maintain its photosynthetic activity and produce traceable signatures.
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Kurosaki, Kenji, and Shu-ichiro Inutsuka. "Giant Impact Events for Protoplanets: Energetics of Atmospheric Erosion by Head-on Collision." Astrophysical Journal 954, no. 2 (September 1, 2023): 196. http://dx.doi.org/10.3847/1538-4357/ace9ba.

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Abstract Numerous exoplanets with masses ranging from Earth to Neptune and radii larger than Earth have been found through observations. These planets possess atmospheres that range in mass fractions from 1% to 30%, reflecting the diversity of atmospheric mass fractions. Such diversities are supposed to be caused by differences in the formation processes or evolution. Here, we consider head-on giant impacts onto planets causing atmosphere losses in the later stage of their formation. We perform smoothed particle hydrodynamic simulations to study the impact-induced atmosphere loss of young super-Earths with 10%–30% initial atmospheric mass fractions. We find that the kinetic energy of the escaping atmosphere is almost proportional to the sum of the kinetic impact energy and self-gravitational energy released from the merged core. We derive the relationship between the kinetic impact energy and the escaping atmosphere mass. The giant impact events for planets of comparable masses are required in the final stage of the popular scenario of rocky planet formation. We show it results in a significant loss of the atmosphere, if the impact is a head-on collision with comparable masses. This latter fact provides a constraint on the formation scenario of rocky planets with substantial atmospheres.
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Zilinskas, Mantas, Yamila Miguel, Paul Mollière, and Shang-Min Tsai. "Atmospheric compositions and observability of nitrogen-dominated ultra-short-period super-Earths." Monthly Notices of the Royal Astronomical Society 494, no. 1 (March 14, 2020): 1490–506. http://dx.doi.org/10.1093/mnras/staa724.

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ABSTRACT We explore the chemistry and observability of nitrogen-dominated atmospheres for ultra-short-period super-Earths. We base the assumption that super-Earths could have nitrogen-filled atmospheres on observations of 55 Cancri e that favour a scenario with a high-mean-molecular-weight atmosphere. We take Titan’s elemental budget as our starting point and using chemical kinetics compute a large range of possible compositions for a hot super-Earth. We use analytical temperature profiles and explore a parameter space spanning orders of magnitude in C/O and N/O ratios, while always keeping nitrogen the dominant component. We generate synthetic transmission and emission spectra and assess their potential observability with the future James Webb Space Telescope (JWST) and ARIEL. Our results suggest that HCN is a strong indicator of a high C/O ratio, which is similar to what is found for H-dominated atmospheres. We find that these worlds are likely to possess C/O > 1.0, and that HCN, CN, and CO should be the primary molecules to be searched for in thermal emission. For lower temperatures (T < 1500 K), we additionally find NH3 in high N/O ratio cases, and C2H4 and CH4 in low N/O ratio cases to be strong absorbers. Depletion of hydrogen in such atmospheres would make CN, CO, and NO exceptionally prominent molecules to look for in the 0.6–5.0 $\rm{\mu m}$ range. Our models show that the upcoming JWST and ARIEL missions will be able to distinguish atmospheric compositions of ultra-short-period super-Earths with unprecedented confidence.
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Kaltenegger, L. "Biomarkers of Habitable Worlds - Super-Earths and Earths." Proceedings of the International Astronomical Union 7, S280 (June 2011): 302–12. http://dx.doi.org/10.1017/s1743921311025063.

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AbstractA decade of exoplanet search has led to surprising discoveries, from giant planets close to their star, to planets orbiting two stars, all the way to the first extremely hot, rocky worlds with potentially permanent lava on their surfaces due to the star's proximity. Observation techniques have reached the sensitivity to explore the chemical composition of the atmospheres as well as physical structure of some detected planets. Recent advances in detection techniques find planets of less than 10 MEarth (so called Super-Earths), among them some that may potentially be habitable. Two confirmed non-transiting planets and several transiting Kepler planetary candidates orbit in the Habitable Zone of their host star. The detection and characterization of rocky and potentially Earth-like planets is approaching rapidly with future ground- and space-missions, that can explore the planetary environments by analyzing their atmosphere remotely. The results of a first generation space mission will most likely be an amazing scope of diverse planets that will set planet formation, evolution as well as our planet in an overall context.
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Misener, William, and Hilke E. Schlichting. "To cool is to keep: residual H/He atmospheres of super-Earths and sub-Neptunes." Monthly Notices of the Royal Astronomical Society 503, no. 4 (March 27, 2021): 5658–74. http://dx.doi.org/10.1093/mnras/stab895.

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ABSTRACT Super-Earths and sub-Neptunes are commonly thought to have accreted hydrogen/helium envelopes, consisting of a few to ten percent of their total mass, from the primordial gas disc. Subsequently, hydrodynamic escape driven by core-powered mass-loss and/or photoevaporation likely stripped much of these primordial envelopes from the lower mass and closer-in planets to form the super-Earth population. In this work, we show that after undergoing core-powered mass-loss, some super-Earths can retain small residual H/He envelopes. This retention is possible because, for significantly depleted atmospheres, the density at the radiative–convective boundary drops sufficiently such that the cooling time-scale becomes shorter than the mass-loss time-scale. The residual envelope is therefore able to contract, terminating further mass-loss. Using analytic calculations and numerical simulations, we show that the mass of primordial H/He envelope retained as a fraction of the planet’s total mass, fret, increases with increasing planet mass, Mc, and decreases with increasing equilibrium temperature, Teq, scaling as $f_\mathrm{ret} \propto M_\mathrm{c}^{3/2} T_\mathrm{eq}^{-1/2} \exp {[M_\mathrm{c}^{3/4} T_\mathrm{eq}^{-1}]}$. fret varies from <10−8 to about 10−3 for typical super-Earth parameters. To first order, the exact amount of left-over H/He depends on the initial envelope mass, the planet mass, its equilibrium temperature, and the envelope’s opacity. These residual hydrogen envelopes reduce the atmosphere’s mean molecular weight compared to a purely secondary atmosphere, a signature observable by current and future facilities. These remnant atmospheres may, however, in many cases be vulnerable to long-term erosion by photoevaporation. Any residual hydrogen envelope likely plays an important role in the long-term physical evolution of super-Earths, including their geology and geochemistry.
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Fujita, Naho, Yasunori Hori, and Takanori Sasaki. "Orbital Evolution of Close-in Super-Earths Driven by Atmospheric Escape." Astrophysical Journal 928, no. 2 (March 30, 2022): 105. http://dx.doi.org/10.3847/1538-4357/ac558c.

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Abstract The increasing number of super-Earths close to their host stars have revealed a scarcity of close-in small planets with 1.5–2.0 R ⊕ in the radius distribution of Kepler planets. The atmospheric escape of super-Earths by photoevaporation can explain the origin of the observed “radius gap.” Many theoretical studies have considered the in situ mass loss of a close-in planet. Planets that undergo atmospheric escape, however, move outward due to the change in the orbital angular momentum of their star–planet systems. In this study, we calculate the orbital evolution of an evaporating super-Earth with a H2/He atmosphere around FGKM-type stars under stellar X-ray and extreme-UV irradiation (XUV). The rate of increase in the orbital radius of an evaporating planet is approximately proportional to that of the atmospheric mass loss during a high stellar XUV phase. We show that super-Earths with a rocky core of ≲10 M ⊕ and a H2/He atmosphere at ≲0.03–0.1 au (≲0.01–0.03 au) around G-type stars (M-type stars) are prone to outward migration driven by photoevaporation. Although the changes in the orbits of the planets would be small, they would rearrange the orbital configurations of compact, multiplanet systems, such as the TRAPPIST-1 system. We also find that the radius gap and the so-called “Neptune desert” in the observed population of close-in planets around FGK-type stars still appear in our simulations. On the other hand, the observed planet population around M-type stars can be reproduced only by a high stellar XUV luminosity model.
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Dissertations / Theses on the topic "Earths atmosphere"

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Saha, Gopal. "Studies on low and high energy particles in cosmic ray extensive air showers observed in the earths atmosphere." Thesis, University of North Bengal, 1997. http://hdl.handle.net/123456789/684.

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Maitra, Santanu Nandan. "Investigation of relative course of Ozone depletion in earths atmosphere and its effects on environment." Thesis, University of North Bengal, 2000. http://hdl.handle.net/123456789/586.

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James, Alexander. "Impacts of meteoric material on Earth's atmosphere : laboratory studies with atmospheric implications." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/16617/.

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Analogues were developed for Interplanetary Dust Particles (IDPs) and Meteoric Smoke Particles (MSPs). Candidate materials were characterised and compared to the present understanding of the nature of IDPs and MSPs. Knowledge and understanding from meteoritics was used to inform open questions in atmospheric chemistry. The elemental composition, structural, surface and size distribution properties of the candidates was compared to micrometeorites and remote measurements of MSPs. Both relatively rare carbonaceous and the more common ordinary chondritic meteorites and terrestrial minerals were shown to be useful analogues for IDPs, whilst synthetic materials were identified as analogues for MSPs. Uptake of HNO3 and HO2, based on laboratory experiments, was implemented in a global modelling study. The uptake processes were assessed to determine the region(s) and season(s) in which they would affect atmospheric chemistry. This heterogeneous chemistry augmented previous understanding of gas-phase chemistry, with a view to understanding all sources and sinks of atmospheric species. Whole Atmosphere Community Climate Model (WACCM) runs including uptake were compared to control runs with only gas-phase chemistry. Uptake of both HNO3 and HO2 was shown to alter chemistry in the polar vortex, including effects on many secondary species and feedbacks on each other. Heterogeneous nucleation kinetics of nitric acid hydrates in Polar Stratospheric Clouds (PSCs) was investigated in the laboratory. SiO2 particles were used as analogues for MSPs processed in acidic solution and the phase which formed was investigated. A newly developed drop freeze assay capable of quantifying heterogeneous nucleation kinetics was used. Nucleation events observed in μl droplets were parameterised using current theoretical models and the results compared to atmospheric observations. The measured heterogeneous nucleation kinetics of the Dihydrate, which then readily converts to the Trihydrate, on SiO2 were shown to be capable of explaining the concentrations of crystals observed in the atmosphere.
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Brissaud, Quentin. "Modélisation numérique des ondes atmosphériques issues des couplages solide/océan/atmosphère et applications." Thesis, Toulouse, ISAE, 2017. http://www.theses.fr/2017ESAE0016/document.

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Cette thèse se penche sur la propagation d’ondes au sein du système coupléTerre-océan-atmosphère. La compréhension de ces phénomènes a une importance majeure pour l’étude de perturbations sismiques et d’explosions atmosphériques notamment dans le cadre de missions spatiales planétaires. Les formes d’ondes issues du couplage fluide-solide permettent d’obtenir de précieuses informations sur la source du signal ou les propriétés des milieux de propagation. On développe donc deux outils numériques d’ordre élevé pour la propagation d’ondes acoustiques et de gravité. L'u en différences finies et se concentre sur le milieu atmosphérique et la propagation d’ondes linéaires dans un milieu stratifié visqueux et avec du vent. Cette méthode linéaire est validée par des solutions quasi-analytiques reposant sur les équations de dispersion dans une atmosphère stratifiée. Elle est aussi appliquée à deux cas d’études : la propagation d’ondes liée à l’impact d’une météorite à la surface de Mars (mission NASA INSIGHT), et la propagation d’ondes atmosphériques liées au tsunami de Sumatra en 2004. La seconde méthode résout la propagation non-linéaire d’ondes gravito-acoustiques dans une atmosphère couplée, avec topographie, à la propagation d’ondes élastiques dans un solide visco-élastique. Cette méthode repose sur sur le couplage d’une formulation en éléments finis discontinus, pour résoudre les équations de Navier-Stokes la partie fluide, par éléments finis continus pour résoudre les équations de l’élastodynamique dans la partie solide. Elle a été validée grâce à des solutions analytiques ainsi que par des comparaisons avec les résultats de la méthode par différences finies
This thesis deals with the wave propagation problem within the Earth-ocean-atmosphere coupled system. A good understanding of the these phenomena has a major importance for seismic and atmospheric explosion studies, especially for planetary missions. Atmospheric wave-forms generated by explosions or surface oscillations can bring valuable information about the source mechanism or the properties of the various propagation media. We develop two new numerical full-wave high-order modeling tools to model the propagation of acoustic and gravity waves in realistic atmospheres. The first one relies on a high-order staggered finite difference method and focus only on the atmosphere. It enables the simultaneous propagation of linear acoustic and gravity waves in stratified viscous and windy atmosphere. This method is validated against quasi-analytical solutions based on the dispersion equations for a stratified atmosphere. It has also been employed to investigate two cases : the atmospheric propagation generated by a meteor impact on Mars for the INSIGHT NASA mission and for the study of tsunami-induced acoutic and gravity waves following the 2004 Sumatra tsunami. The second numerical method resolves the non-linear acoustic and gravity wave propagation in a realistic atmosphere coupled, with topography, to the elastic wave propagation in a visco-elastic solid. This numerical tool relies on a discontinuous Galerkin method to solve the full Navier-Stokes equations in the fluid domain and a continuous Galerkin method to solve the elastodynamics equations in the solid domain. It is validated against analytical solutions and numerical results provided by the finite-difference method
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Alei, Eleonora. "Habitability Studies of Super Earths atmospheres." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422351.

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Over the centuries, mankind always wondered whether other worlds existed, as well as other life forms upon their surfaces. This topic was considered “science-fiction” a few decades ago, but now it’s becoming more and more realistic: actually, different planets do exist, and some of them could bear life. Up to date, a database of more than 7000 planets or candidates is continuously updated, as current facilities keep on discovering new ones – a simple estimate suggests that in our galaxy tens of billions of new planets await to be revealed. Being extrasolar planetology a relatively new field of astrophysics, many things need to be set and done. In this case, a full characterization of the different atmospheres terrestrial exoplanets are likely to have is needed to correctly understand observational data; also, one should retrieve information about their formation and be able to presume that some form of life exists on the surface. To do that, theoretical modeling is needed: by simulating a simple imaginary exoplanet, one could have a better understanding of how all active processes interact within the system and what observable features they express so that they could be recognized when observing a real exoplanet. In this Ph.D. project, I explored the topic in various ways, starting with an overview about the detection techniques, the current knowledge about Super Earths, which are massive terrestrial exoplanets, and the concept of habitability. In the framework of a standardized, Virtual Observatory (VO) aware treatment of the exoplanets, I developed Exo-MerCat, which collects data from the most important online archives and merges the information while correcting nomenclature, status, and coordinate issues. This catalog is now a VO resource and has been positively accepted by the International Virtual Observatory Alliance (IVOA), as well as being used for PLATO and ARIEL space missions. Exo-MerCat allowed retrieving the sample of known Super Earths, which is then used as input to create a grid of atmospheric models to be run with the 1D radiative-convective model MAGRATHEA which I contributed to develop. MAGRATHEA can model Earth and Mars-like atmospheres, covering a wide range of the physical and chemical parameter space. It is able to calculate the radiative-convective equilibrium solution of an atmosphere in a very short time (a few hours of computational time), allowing us to fulfill a grid of 18000 atmospheric models of theoretical planets and 2400 ones of observed planets, as retrieved by the Exo-MerCat catalog. These models can be useful to study under which physical and atmospheric conditions it is possible to find liquid water on the surface of the planet, an essential requirement for the habitability of exoplanets. The atmospheric pressure-temperature profiles for the observed Super Earths grid, as retrieved by MAGRATHEA, were then used as an input for the Exoplanet Ozone Model to produce the corresponding ozone profile. The code is, at present, still at its early stages, but can efficiently produce the ozone profile of an atmosphere by solving the (photo-induced and thermal) chemistry of the oxygen-related species. The laboratory experiments performed at the Biology Department of the University of Padua, within the “Atmosphere in a Test-Tube project”, can benefit from the theoretical results from MAGRATHEA. The physical and chemical conditions at the surface are reproduced in the laboratory, forming exotic environments at which cyanobacteria are exposed. The study of the survival rate and the variation of the chemical composition caused by the presence of biological activity can be thus performed: this is indispensable in order to understand if, and when, a habitable planet can be actually inhabited.
Nei secoli, ci siamo sempre chiesti se esistessero altri mondi e altre forme di vita sulla superficie di questi. Questo argomento è stato considerato spesso “fantascienza” fino a pochi decenni fa, ma ora sta diventando sempre più realistico: in realtà, pianeti diversi esistono ed alcuni di essi possono ospitare la vita. Ad oggi, un archivio di più di 7000 pianeti confermati o candidati è costantemente aggiornato, al passo con gli strumenti che ne scoprono sempre di più - solo nella nostra Galassia, decine di miliardi di nuovi pianeti aspettano di essere scoperti. Essendo la planetologia extrasolare un campo relativamente nuovo dell'astrofisica, molte cose devono essere ancora studiate. In questo caso, una caratterizzazione più dettagliata delle possibili atmosfere di esopianeti di tipo terrestre è necessaria per comprendere meglio le osservazioni; inoltre, bisognerebbe ricavare informazioni sulla loro formazione e poter presumere se, ed in quali casi, forme di vita potrebbero esistere su quei pianeti. Per fare ciò, un approccio teorico è necessario: simulando un pianeta in maniera semplificata, si potrebbe avere una migliore comprensione di come tutti i processi attivi interagiscono tra loro e quali osservabili producono, affinché possano essere identificate quando si osserva un vero esopianeta. In questo progetto di Dottorato, ho esplorato l'argomento da diversi punti di vista, iniziando con una sintesi dei metodi di scoperta, di ciò che è noto ad oggi sulle Super Terre (pianeti terrestri massivi), e del concetto di abitabilità. In una prospettiva di un trattamento standardizzato dei dati, il quale possa rientrare nei canoni del Virtual Observatory (VO), ho sviluppato Exo-MerCat al fine di collezionare dati dai più importanti archivi online, incrociando le informazioni e correggendo problemi di nomenclatura, status e coordinate. Questo catalogo è ora una risorsa VO ed è stato accettato positivamente dall'International Virtual Observatory Alliance (IVOA), oltre ad essere usato per le missioni spaziali PLATO e ARIEL. Exo-MerCat ha permesso di ricavare l'insieme di Super Terre note, usato poi per creare una griglia di modelli atmosferici utilizzata dal modello 1D radiativo-convettivo MAGRATHEA, che ho contribuito a sviluppare. MAGRATHEA riesce a riprodurre atmosfere di tipo terrestre e marziano, coprendo un largo intervallo di parametri fisici e chimici. Il codice calcola il profilo di equilibrio radiativo-convettivo di una atmosfera in poche ore di tempo computazionale, consentendoci di riempire una griglia di 18000 modelli di pianeti teorici e una di 2400 modelli di pianeti osservati, ricavati dall'insieme prodotto da Exo-MerCat. Questi modelli possono essere utili per studiare sotto quali condizioni fisiche e atmosferiche è possibile trovare acqua liquida sulla superficie di un pianeta, requisito essenziale per l'abitabilità degli esopianeti. I modelli atmosferici delle Super Terre osservate ricavati da MAGRATHEA sono stati usati come input per l'Exoplanet Ozone Model al fine di produrre la concentrazione di ozono corrispondente ai profili stessi. Questo codice è, al momento, ancora preliminare, ma può riprodurre il profilo dell'abbondanza di ozono di una atmosfera risolvendo la chimica foto-indotta e termica delle specie legate all'ossigeno. I risultati teorici ottenuti dai vari codici sono utili agli esperimenti di laboratorio effettuati al Dipartimento di Biologia dell'Università di Padova. Considerando alcune atmosfere calcolate da MAGRATHEA, si possono riprodurre le condizioni fisiche e chimiche alla superficie in laboratorio, formando atmosfere esotiche ed esponendo cianobatteri a queste. Lo studio della sopravvivenza e dell'adattamento dei batteri, così come della variazione della composizione chimica causata dall'attività biologica, può essere eseguito. Ciò è indispensabile per comprendere se, e sotto quali condizioni, un pianeta abitabile può essere effettivamente abitato.
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Annaloro, Julien. "Elaboration of collisional-radiative models applied to atmospheric entry into the Earth and Mars atmospheres." Phd thesis, Université de Rouen, 2013. http://tel.archives-ouvertes.fr/tel-00915497.

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L'entrée hypersonique d'un objet dans la haute atmosphère d'une planète entraîne la création d'un plasma à la suite de la compression très intense du gaz incident à l'objet. Cette compression s'effectue dans une couche de choc présentant une grande richesse en déséquilibres dont la méconnaissance limite notre capacité à prédire avec précision les contributions convective, radiative et catalytique de la densité de flux d'énergie pariétale, pourtant cruciale pour l'optimisation du dimensionnement du système de protection thermique de l'objet. Les contributions précédentes dépendent fortement des densités de population des états excités qui échappent à un comportement de type boltzmanien et présentent une distribution dépendant des phénomènes élémentaires collisionnels et radiatifs. Dans ces circonstances, le but de ces travaux était d'étudier, dans les situations d'entrée dans l'atmosphère de Mars et de la Terre, le comportement des états excités de mélanges complexes (CO2 -N2 -Ar et N2 -O2 -Ar, respectivement) basée sur le développement de modèles collisionnels-radiatifs (CR) électro-vibrationnels spécifiques. Deux modèles CR ont ainsi été développés : CoRaM-MARS pour l'atmosphère martienne (22 espèces, 10^6 processus élémentaires) et CoRaM-AIR pour l'atmosphère terrestre (13 espèces, 500000 processus élémentaires). Ces modèles, mis en œuvre dans une approche lagrangienne à pression et température constantes dans des conditions thermodynamiques représentatives des situations d'entrée (notamment le cas FIRE II pour les entrées terrestres), ont montré que le rayonnement présente une influence très faible sur la cinétique des mélanges étudiés et que les écarts à la distribution de Boltzmann sont systématiques. Le très grand nombre d'états à prendre en compte interdit une intégration directe des modèles CR précédents dans des codes aérodynamiques. Cependant, une réduction à l'azote de ces modèles a été réalisée. Le modèle CR ainsi constitué (CoRaM-N2 , 5 espèces, 150 états, 40000 processus élémentaires) a été intégré à un code eulérien traitant les écoulements monodimensionnels d'après-choc ou de tuyère divergente. L'accord avec des résultats expérimentaux acquis en tube à choc à fort nombre de Mach est très satisfaisant. Pour des applications 2D ou 3D, des taux globaux ont par ailleurs été déterminés théoriquement pour (1) l'ionisation/recombinaison par impact électronique de l'azote, de l'oxygène, du carbone et de l'argon, (2) la dissociation/recombinaison de N2 , O2 par impact de N, N2 , O, O2 et (3) la dissociation/recombinaison de CO2 par impact de lourd. La comparaison avec des résultats expérimentaux montre un accord en général très satisfaisant. Les taux directs et inverses étant calculés de manière indépendante, il est montré que leur rapport s'écarte de la constante d'équilibre globale correspondante à mesure que la température augmente.
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Morris, Paul. "Remote sensing of the Earth's atmosphere." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317735.

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Mantini, Jennifer Lynn. "A LABORATORY INVESTIGATION OF THE STRUCTURE OF TORNADO-LIKE VORTICES THROUGH MEASUREMENT OF SURFACE PRESSURE." Miami University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=miami1218653459.

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Schofield, Daniel Paul, and n/a. "Hydrated complexes in the earth�s atmosphere." University of Otago. Department of Chemistry, 2005. http://adt.otago.ac.nz./public/adt-NZDU20070427.120933.

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The interaction between sunlight and our atmosphere is one of the most fundamental processes affecting weather and climate. The majority of the Sun�s radiation is produced in the ultraviolet, visible and near-infrared regions of the electromagnetic spectrum. These spectral regions correspond to the energies of vibrational overtone and electronic transitions. The composition of our atmosphere is complex, and many trace species have a large influence on its chemistry and dynamics. Hydrogen bound hydrated complexes are trace species that could play an important role in the Earth�s atmosphere. However, before this role can be quantified, spectral identification and characterisation of these complexes is essential. We have developed vibrational local mode Hamiltonians to simulate the absorption spectra of hydrated complexes. To test the approximations made in the vibrational model, we have peformed calculations on the diatomics OH, HF and CO, which can be considered to act as pure local modes. When highly correlated ab initio methods and large basis sets are used to calculate the potential energy and dipole moment curve, the simulated vibrational transitions of the diatomics are in excellent agreement with experiment. We have derived approximate vibrational Hamiltonians which describe the OH-stretching and HOH-bending modes of vibration in the complexes H₂O�H₂O, H₂O�HO₂ and H₂O�HO. The calculated spectrum of H₂O�H₂O has been used to assess its atmospheric importance, and to succesfully guide experimental efforts to detect H₂O�H₂O in the laboratory and the Earth�s atmosphere. The calculated transition energies and intensities of H₂O�H₂O and H₂O�HO are in good agreement with experimental matrix isolation and gas-phase studies. To investigate the effect of low frequency modes on OH-stretching overtone spectra we have simulated the spectrum of HOONO. We have derived a Hamiltonian that couples the NOOH-torsional mode to the high frequency OH-stretching and OOH-bending modes. The simulated spectrum is in good agreement with the experimentally observed spectrum. We find that the OH-stretching spectra are perturbed strongly only if the barrier to torsion is low. We have also investigated changes in the electronic spectrum of hydrated complexes and the corresponding parent monomers. Upon complex formation, the lowest-lying electronic transition in the hydroxyl radical is strongly redshifted outside the region of monomeric absorption.
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Kazil, Jan, Philip Stier, Kai Zhang, Johannes Quaas, Stefan Kinne, D. O'Donnell, Sebastian Rast, et al. "Aerosol nucleation and its role for clouds and Earth’s radiative forcing in the aerosol-climate model ECHAM5-HAM." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-185342.

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Nucleation from the gas phase is an important source of aerosol particles in the Earth’s atmosphere, contributing to the number of cloud condensation nuclei, which form cloud droplets. We have implemented in the aerosolclimate model ECHAM5-HAM a new scheme for neutral and charged nucleation of sulfuric acid and water based on laboratory data, and nucleation of an organic compound and sulfuric acid using a parametrization of cluster activation based on field measurements. We give details of the implementation, compare results with observations, and investigate the role of the individual aerosol nucleation mechanisms for clouds and the Earth’s radiative forcing. The results of our simulations are most consistent with observations when neutral and charged nucleation of sulfuric acid proceed throughout the troposphere and nucleation due to cluster activation is limited to the forested boundary layer. The globally averaged annual mean contributions of the individual nucleation processes to total absorbed solar short-wave radiation via the direct, semi-direct, indirect cloud-albedo and cloud-lifetime effects in our simulations are −1.15 W/m2 for charged H2SO4/H2O nucleation, −0.235 W/m2 for cluster activation, and −0.05 W/m2 for neutral H2SO4/H2O nucleation. The overall effect of nucleation is −2.55 W/m2, which exceeds the sum of the individual terms due to feedbacks and interactions in the model. Aerosol nucleation contributes over the oceans with −2.18 W/m2 to total absorbed solar short-wave radiation, compared to −0.37 W/m2 over land. We explain the higher effect of aerosol nucleation on Earth’s radiative forcing over the oceans with the larger area covered by ocean clouds, due to the larger contrast in albedo between clouds and the ocean surface compared to continents, and the larger susceptibility of pristine clouds owing to the saturation of effects. The large effect of charged nucleation in our simulations is not in contradiction with small effects seen in local measurements: over southern Finland, where cluster activation proceeds efficiently, we find that charged nucleation of sulfuric acid and water contributes on average less than 10% to ultrafine aerosol concentrations, in good agreement with observations.
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Books on the topic "Earths atmosphere"

1

Reilly, Carmel. Earth's atmosphere. New York: Marshall Cavendish Benchmark, 2012.

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Borisovich, Ronov Aleksandr, and I͡A︡nshin Aleksandr Leonidovich 1911-, eds. History of the Earth's atmosphere. Berlin: Springer-Verlag, 1987.

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B, DeMore William, ed. Photochemistry of planetary atmospheres. New York: Oxford University Press, 1999.

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Kahn, Ralph. Comparative planetology and the atmosphere of Earth: A report to the Solar System Exploration Division, National Aeronautics and Space Administration. Pasadena, Calif: Jet Propulsion Laboratory, California Institute of Technology, 1989.

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David, Brodie, Nuffield Modular Sciences Project, and Nuffield-Chelsea Curriculum Trust, eds. Earth and atmosphere. Harlow: Published for the Nuffield-ChelseaCurriculum Trust by Longman, 1993.

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Syun-Ichi, Akasofu, and Kamide Y, eds. The Solar wind and the earth. Tokyo, Japan: Terra Scientific Pub. Co., 1987.

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L, Grose William, COSPAR. Interdisciplinary Scientific Commission A. Topical Meeting, COSPAR. Interdisciplinary Scientific Commission C. Topical Meeting, COSPAR Plenary Meeting, and COSPAR, eds. The earth's middle atmosphere. Oxford: Published for the Committee on Space Research by Pergamon Press, 1994.

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Oliver, Ray. Earth, atmosphere and space. (S.l.): Thornes, 1992.

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L, Erukhimova Tatiana, ed. Atmospheric thermodynamics: Elementary physics and chemistry. Cambridge, UK: Cambridge University Press, 2009.

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Wayne, Richard P. Chemistry of atmospheres: An introduction to the chemistry of the atmospheres of Earth, the planets, and their satellites. 2nd ed. Oxford [Oxfordshire]: Oxford University Press, 1985.

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Book chapters on the topic "Earths atmosphere"

1

Funke, B., M. López-Puertas, M. García-Comas, D. Bermejo-Pantaleón, G. P. Stiller, and T. von Clarmann. "The Impact of Energetic Particle Precipitation on the Earths Atmosphere." In Astrophysics and Space Science Proceedings, 181–89. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-11250-8_18.

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Pinti, Daniele L. "Earth’s Atmosphere." In Encyclopedia of Earth Sciences Series, 1–11. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-39193-9_210-1.

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Pinti, Daniele L. "Earth’s Atmosphere." In Encyclopedia of Earth Sciences Series, 383–92. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-39312-4_210.

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Yiğit, Erdal. "Earth’s Atmosphere and Geospace Environment." In Atmospheric and Space Sciences: Neutral Atmospheres, 41–51. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-21581-5_4.

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Léna, Pierre. "The Earth’s Atmosphere." In Astronomy and Astrophysics Library, 23–57. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-662-02554-3_2.

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Barrass, Robert. "Air: Earth’s atmosphere." In Mastering Science, 115–25. London: Macmillan Education UK, 1991. http://dx.doi.org/10.1007/978-1-349-11075-9_11.

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Purkis, Samuel, and Victor Klemas. "Monitoring Earth's atmosphere." In Remote Sensing and Global Environmental Change, 241–71. West Sussex, UK: John Wiley & Sons Ltd, 2013. http://dx.doi.org/10.1002/9781118687659.ch11.

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Livanov, Dmitry. "The Earth’s Atmosphere." In The Physics of Planet Earth and Its Natural Wonders, 123–57. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-33426-9_4.

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Weiland, Claus. "The Earth Atmosphere." In Computational Space Flight Mechanics, 215–21. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-13583-5_10.

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Grenfell, John Lee. "Earth-like Atmosphere." In Encyclopedia of Astrobiology, 706. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_5311.

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Conference papers on the topic "Earths atmosphere"

1

Jalufka, Nelson W. "High Resolution Spectroscopy." In Inaugural Forum for the Research Center for Optical Physics. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/rcop.1993.tpls16.

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Water vapor is an important species in the earths atmosphere. It plays a major role in many atmospheric processes including weather, climate and atmospheric photochemistry. The distribution of water vapor in the atmosphere is highly variable and if we are to relate its variability to atmospheric effects, its spatial and temporal variability must be understood. Remote measurements of water vapor distribution in the atmosphere frequently relies on differential absorption lidar (DIAL) techniques. These techniques require accurate spectroscopic data for the species of interest. These data include line position (wavelength) , absorption coefficients, pressure broadening parameters and pressure shift parameters. Temperature effects on these parameters is also important as it is more convenient to work with spectral lines which are relatively insensitive to temperature variations. DIAL measurements must be made in a spectral region where the absorption cross sections have appropriate values for the density and measurement range of interest Optimum measurements are made in the range where the optical depth (one way) has a value near unity. To extend Dial measurements of water vapor into the stratosphere, where water vapor is less dense than in the troposphere, the water vapor band in the region of 940 nm is appropriate due to its stronger absorption.
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Kumer, JB, RS Benson, LW Sterritt, WJ Rosenberg, and AE Roche. "GLitter Absorption Etalon Spectrometer (GLAES) concept for remotely sounding minor and trace molecular species." In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/orsa.1991.ome1.

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High spectral resolution (≈.005 to .05 cm–1) ground based solar infrared absorption experiments have demonstrated capability to sound atmospheric species. A sample of these includes HCN, C2H2, C2H0, CH4, NO2, and HCl from solar absorption spectra obtained in the 3 to 3.5 jam region. The GLAES concept is aimed at obtaining similar absorption spectra in light that passes through the atmosphere and is reflected from the earths surface back out to the satellite. This would enable the solar absorption technique to be expanded from a limited number of ground base cites to satellite borne global mapping. Spectral resolution of the order a few hundredths cm-1 is necessary to discriminate against absorption continuua introduced by the reflecting media and the atmosphere, and will enhance identification of the target molecular species absorption lines. The GLAES approach involves tuneable piezo-electric etalons and a CVF to obtain spectra across an interval ≈ 1 cm-1 any where on the range ≈ 2.5 to 4.5 um, with a scan time of ≈ 0.1 s. Several hundredths cm-1 resolution can be achieved with a 7.7 mrad field of view for example. The corresponding perpendicular footprint is ≈ 5.6 km from 700 km polar orbit, and ≈ 275 km from geosynchronous. The most effective mode of operation is to use a front end mirror to point at the solar specular point on a body of water (lakes, ocean, etc.) larger than the footprint. At 3.5 μm and 60 deg angle of solar incidence for example the glitter radiance (≈ corrected for continous atmospheric absorption) is of the order 3.5×10–7 w/cm–2 sr–1(cm–1)–1. This is considerably larger than 290 K black body radiance ≈ 1.9×10–8 w/cm–2sr–1(cm–1)–1, or solar Lambertian (typical terrain) reflected radiance of ≈2.2×10–8 w/cm–2sr–1(cm–1)–1. By using the solar glitter and 4 inch aperture/etalon diameters a S/N ≥ 100 per spectral sample can be achieved by using an InSb PV detector cooled to ≈ 65 K. This S/N is more than adequate to detect 1 % absorption lines (which typically include several spectral samples). The detector cooling could be achieved by Stirling cycle refrigerators, or by passive radiation for appropriate satellite operations/accomodation. Modest spectrometer cooling of the order ≈ 160 K is required. No optics cooling is required. A sun synchronous near-polar orbit at altitude ≈ 700 km, with orbital plane ⊥ to the direction to the sun is an interesting candidate for GLAES deployment. It would provide for nearly ideal viewing into ≈ 75 degree solar incident glitter, for nearly continous coverage, and is the best low altitude orbit for passive radiative cooling. More instrument description, simulated solar glitter absorption spectra, and estimates for the retrievability of mixing ratio and/or column density for selected molecular species will be presented.
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Diner, David J. "Atmospheric Remote Sensing with the Eos Multi-angle Imaging SpectroRadiometer." In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/orsa.1990.md5.

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The Multi-angle Imaging SpectroRadiometer (MISR) experiment is an Instrument Investigation selected for flight aboard the first NASA Earth Observing System polar platform, Eos-A. The purpose of the MISR investigation is to study the effects of geophysical processes and human activities on the Earth’s ecology and climate. Scientific objectives include study of the climatic and environmental impacts of atmospheric aerosols, characterization of heterogeneous cloud fields and their impact on the shortwave radiation budget, and investigation of biosphere-atmosphere interactions and ecosystem change. A detailed understanding of the causes and effects of regional and global change will require long-term monitoring of the Earth system. MISR is a unique component of the Eos instrument suite in that it will systematically acquire multispectral images of the angular reflectance signatures of terrestrial scenes. Theoretical simulations, ground-based measurements, and remotely-sensed observations of aerosol-laden atmospheres, cloud fields, and vegetated landscapes demonstrate the necessity of multi-angle data for climatological and biogeophysical studies. While the spectral coverage and resolution of nadir-viewing imaging spectrometers provide invaluable information on chemical composition, the angular variation of reflectance furnishes the means of inferring physical quantities related to geometric and optical structure, radiative energy transfer, and biosphere-atmosphere mass exchange.
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Strow, L. Larrabee. "A Signal-Processing Approach for the Retrieval of Global Tropospheric CO Using the Atmospheric Infrared Sounder (AIRS)." In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/orsa.1993.the.9.

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One goal of the Earth Observing Systems (EOS) is to measure concentrations of key atmospheric gases on a global scale in order to understand biogeochemical cycles in both the natural, unpolluted atmosphere, and in regions where anthropogenic activities have perturbed concentrations of gas-phase species. A particular concern in tropospheric chemistry is that increasing levels of carbon monoxide (CO) may lead to a decrease in atmospheric hydroxyl (OH) which would reduce the atmosphere's ability to scavenge other trace gases.
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Eloranta, E. W., D. P. Wylie, P. Piironen, and A. Piironen. "Lidar Verification of Tropical Cirrus Cloud Measurements Derived from GOES-8 Data Using the CO2 Slicing Algorithm." In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/orsa.1997.otub.2.

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Cirrus clouds are thought to play an important role in determining the radiative equilibrium temperature of the earth. Their cold temperature relative to the earth’s surface and lower clouds tends to decrease the effective radiative temperature of the the earth, while their relative transparency to incoming sunshine allows heating of lower layers of the atmosphere.
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Freitas, Christopher J., and Geoffrey Crowley. "Space Weather Simulation on Networks of Workstations." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-1241.

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Abstract Space weather refers to the complex phenomena that develop in the near-earth region of space and the upper layers of earth’s atmosphere. Presented in this paper are the elements required to develop a parallel computer algorithm for the real-time simulation of this highly dynamic region of space. The architecture developed for this parallel algorithm is based on Networks of Workstations connected by highspeed data links, and executed using the Parallel Virtual Machine library. This paper reviews the progress completed in developing a real-time analysis system for prediction of upper-atmospheric conditions.
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Wood, S. A., G. D. Emmitt, and L. S. Wood. "Global Three-Dimensional Distribution of LAWS Observations Based Upon Aerosols, Water Vapor and Clouds." In Optical Remote Sensing of the Atmosphere. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/orsa.1991.omc4.

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A space-based Doppler Lidar Atmospheric Wind Sounder (LAWS) has been proposed by NASA as a facility instrument for the NASA Earth Observing System. Simpson Weather Associates, Inc. has developed LAWS Simulation Models (LSM) that are coupled with Global Circulation Models (GCM) to evaluate the potential impact of global wind observations on the basic understanding of the earth’s atmosphere and on the predictive skills of current forecast models (GCM and regional scale). This paper uses the LSM to examine the three dimensional distribution of LAWS’ observations over the globe. Such a study must consider the effects of atmospheric aerosols, molecular attenuation of the lidar signal, opaque clouds, and the presence of thin cirrus clouds.
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Whitlock, C. H., J. T. Suttles, B. R. Barkstrom, and S. R. LeCroy. "Determination of Spectral Properties of the Earth Radiation Budget at Selected Sites." In Optical Remote Sensing. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/ors.1985.tuc12.

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The Earth Radiation Budget Experiment (ERBE) satellite system is concerned with the measurement of total radiation both entering and leaving the Earth-atmosphere system. In order to improve scientific understanding of radiation phenomena, optical experiments are being conducted in support of the satellite measurements to better determine both stratospheric and tropospheric components for specific atmospheric and surface albedo conditions. Such data may also be used to validate various radiative transfer models which are used to analyze data from other satellite systems. This paper describes the combination of radiometric and lidar measurements as well as analytical procedures which are used for spectral characterization of both downwelling and upwelling radiation in stratified atmospheres. Results are given from the first in the series of experiments.
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Manninen, Hanna E., Hannes Tammet, Antti Mäkelä, Jussi Haapalainen, Sander Mirme, Tuomo Nieminen, Alessandro Franchin, Tuukka Petäjä, Markku Kulmala, and Urmas Hõrrak. "Atmospheric electricity and aerosol-cloud interactions in earth’s atmosphere." In NUCLEATION AND ATMOSPHERIC AEROSOLS: 19th International Conference. AIP, 2013. http://dx.doi.org/10.1063/1.4803390.

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Baker, Wayman E. "Science Advances Anticipated with the Laser Atmospheric Wind Sounder." In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/clr.1991.thb1.

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Knowledge of the global wind field is widely recognized as fundamental to advancing our understanding and prediction of the total Earth system. The motion of the atmosphere directly affects a wide-range of geophysical processes including: the horizontal transport of momentum, moisture, chemical constituents and aerosols, the evaporation of water and heat from the land and oceans, and atmospheric teleconnections, such as the influence of the tropical Pacific on the circulation of the northern hemisphere middle latitudes. An accurate depiction of the atmospheric motion is also a key parameter for improving the skill of weather forecasts. Yet, because wind profiles are primarily measured by land-based, balloon-tethered instruments, the oceanic areas (covering roughly three quarters of the Earth’s surface) and many regions of the less-developed tropical and southern hemisphere land areas are poorly observed. The gap between our requirements for global wind data and their availability continues to widen. For example, as faster computers become available to model the atmosphere with ever increasing resolution and sophistication, our ability to do so is hampered because of the lack of data, particularly wind profiles.
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Reports on the topic "Earths atmosphere"

1

Wehr, Tobias, ed. EarthCARE Mission Requirements Document. European Space Agency, November 2006. http://dx.doi.org/10.5270/esa.earthcare-mrd.2006.

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ESA's EarthCARE (Cloud, Aerosol and Radiation Explorer) mission - scheduled to be launched in 2024 - is the largest and most complex Earth Explorer to date and will advance our understanding of the role that clouds and aerosols play in reflecting incident solar radiation back into space and trapping infrared radiation emitted from Earth's surface. The mission is being implemented in cooperation with JAXA (Japan Aerospace Exploration Agency). It carries four scientific instruments. The Atmospheric Lidar (ATLID), operating at 355 nm wavelength and equipped with a high-spectral resolution and depolarisation receiver, measures profiles of aerosols and thin clouds. The Cloud Profiling Radar (CPR, contribution of JAXA), operates at 94 GHz to measure clouds and precipitation, as well as vertical motion through its Doppler functionality. The Multi-Spectral Imager provides across-track information of clouds and aerosols. The Broad-Band Radiometer (BBR) measures the outgoing reflected solar and emitted thermal radiation in order to derive broad-band radiative fluxes at the top of atmosphere. The Mission Requirement Document defines the scientific mission objectives and observational requirements of EarthCARE. The document has been written by the ESA-JAXA Joint Mission Advisory Group for EarthCARE.
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Cornelisse, Tara, and Nadav Gazit. Introduction to Climate Change. American Museum of Natural History, 2014. http://dx.doi.org/10.5531/cbc.ncep.0158.

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This presentation on climate change is divided into two parts: Part 1 explores Earth’s climate system: Earth’s energy balance, glacial and solar cycles, natural variability buy papers (e.g., Niño and Southern Oscillation), and how volcanoes may effect climate. Part 2 delves into anthropogenic climate change: how the atmospheric chemical composition is changing, impacts of climate change that have already been observed, and projections of possible future scenarios.
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Rahlin, Alexandra S. The Effect of the Earth's Atmosphere on LSST Photometry. Office of Scientific and Technical Information (OSTI), August 2006. http://dx.doi.org/10.2172/891240.

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Miller, Thomas M. Laser-Based Studies of Molecular Ion Dynamics in the Earth's Atmosphere. Fort Belvoir, VA: Defense Technical Information Center, June 1986. http://dx.doi.org/10.21236/ada171885.

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Hege, E. K. Investigations of High Resolution Imaging through the Earth's Atmosphere Using Speckle Interferometry. Fort Belvoir, VA: Defense Technical Information Center, March 1987. http://dx.doi.org/10.21236/ada189295.

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Horsley, M., L. Simms, B. Bauman, P. Cameron-smith, and R. Kane. Instrumenting a Fleet of Small Satellites for Monitoring the Earth's Upper Atmosphere. Office of Scientific and Technical Information (OSTI), October 2019. http://dx.doi.org/10.2172/1571372.

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Balmforth, Neil J., and Colm-cille Caulfield. 2018 program of studies: sustainable fluid dynamics. Woods Hole Oceanographic Institution., 2023. http://dx.doi.org/10.1575/1912/67612.

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The 2018 GFD Program theme was Sustainable Fluid Dynamics with Professor Andrew Woods of the University of Cambridge serving as principal lecturer. Andy showed the audience in the cottage and on the porch how to find similarity solutions everywhere, from deep in the earth to high in the atmosphere. He expanded on his lectures with the fellows during “Andy time”, and stayed on throughout the summer to participate in the traditional debates on the porch with participants old and new. Andy also contributed enthusiastically to the supervision of the fellows, particularly when there was an opportunity to squirt food dye into an experiment.
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Vadas, Sharon L. Observation and Modeling of Tsunami-Generated Gravity Waves in the Earth's Upper Atmosphere. Fort Belvoir, VA: Defense Technical Information Center, October 2014. http://dx.doi.org/10.21236/ada610028.

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Vadas, Sharon L. Observation and Modeling of Tsunami-Generated Gravity Waves in the Earth's Upper Atmosphere. Fort Belvoir, VA: Defense Technical Information Center, January 2013. http://dx.doi.org/10.21236/ada587974.

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Vadas, Sharon L. Observation and Modeling of Tsunami-Generated Gravity Waves in the Earth's Upper Atmosphere. Fort Belvoir, VA: Defense Technical Information Center, October 2015. http://dx.doi.org/10.21236/ada627138.

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