Journal articles: 'Atmospheric changes'

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Piver, W. T. "Global atmospheric changes." Environmental Health Perspectives 96 (December 1991): 131–37. http://dx.doi.org/10.1289/ehp.9196131.

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Johnstone, C. P., M. Güdel, H. Lammer, and K. G. Kislyakova. "Upper atmospheres of terrestrial planets: Carbon dioxide cooling and the Earth’s thermospheric evolution." Astronomy & Astrophysics 617 (September 2018): A107. http://dx.doi.org/10.1051/0004-6361/201832776.

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Context.The thermal and chemical structures of the upper atmospheres of planets crucially influence losses to space and must be understood to constrain the effects of losses on atmospheric evolution.Aims.We develop a 1D first-principles hydrodynamic atmosphere model that calculates atmospheric thermal and chemical structures for arbitrary planetary parameters, chemical compositions, and stellar inputs. We apply the model to study the reaction of the Earth’s upper atmosphere to large changes in the CO2abundance and to changes in the input solar XUV field due to the Sun’s activity evolution from 3 Gyr in the past to 2.5 Gyr in the future.Methods.For the thermal atmosphere structure, we considered heating from the absorption of stellar X-ray, UV, and IR radiation, heating from exothermic chemical reactions, electron heating from collisions with non-thermal photoelectrons, Joule heating, cooling from IR emission by several species, thermal conduction, and energy exchanges between the neutral, ion, and electron gases. For the chemical structure, we considered ~500 chemical reactions, including 56 photoreactions, eddy and molecular diffusion, and advection. In addition, we calculated the atmospheric structure by solving the hydrodynamic equations. To solve the equations in our model, we developed the Kompot code and have provided detailed descriptions of the numerical methods used in the appendices.Results.We verify our model by calculating the structures of the upper atmospheres of the modern Earth and Venus. By varying the CO2abundances at the lower boundary (65 km) of our Earth model, we show that the atmospheric thermal structure is significantly altered. Increasing the CO2abundances leads to massive reduction in thermospheric temperature, contraction of the atmosphere, and reductions in the ion densities indicating that CO2can significantly influence atmospheric erosion. Our models for the evolution of the Earth’s upper atmosphere indicate that the thermospheric structure has not changed significantly in the last 2 Gyr and is unlikely to change signficantly in the next few Gyr. The largest changes that we see take place between 3 and 2 Gyr ago, with even larger changes expected at even earlier times.

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Aplin, K. L., C. J. Scott, and S. L. Gray. "Atmospheric changes from solar eclipses." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2077 (September 28, 2016): 20150217. http://dx.doi.org/10.1098/rsta.2015.0217.

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This article reviews atmospheric changes associated with 44 solar eclipses, beginning with the first quantitative results available, from 1834 (earlier qualitative accounts also exist). Eclipse meteorology attracted relatively few publications until the total solar eclipse of 16 February 1980, with the 11 August 1999 eclipse producing the most papers. Eclipses passing over populated areas such as Europe, China and India now regularly attract scientific attention, whereas atmospheric measurements of eclipses at remote locations remain rare. Many measurements and models have been used to exploit the uniquely predictable solar forcing provided by an eclipse. In this paper, we compile the available publications and review a subset of them chosen on the basis of importance and novelty. Beyond the obvious reduction in incoming solar radiation, atmospheric cooling from eclipses can induce dynamical changes. Observations and meteorological modelling provide evidence for the generation of a local eclipse circulation that may be the origin of the ‘eclipse wind’. Gravity waves set up by the eclipse can, in principle, be detected as atmospheric pressure fluctuations, though theoretical predictions are limited, and many of the data are inconclusive. Eclipse events providing important early insights into the ionization of the upper atmosphere are also briefly reviewed. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’.

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Trenberth, Kevin E. "Atmospheric circulation climate changes." Climatic Change 31, no. 2-4 (December 1995): 427–53. http://dx.doi.org/10.1007/bf01095156.

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Lee, Ariel, Mehdi Abouzari, and Hamid Djalilian. "Symptom: Dizziness with Atmospheric Changes." Hearing Journal 73, no. 10 (October 2020): 30,32,33. http://dx.doi.org/10.1097/01.hj.0000719812.50617.36.

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Choi, Nakbin, Myong-In Lee, Dong-Hyun Cha, Young-Kwon Lim, and Kyu-Myong Kim. "Decadal Changes in the Interannual Variability of Heat Waves in East Asia Caused by Atmospheric Teleconnection Changes." Journal of Climate 33, no. 4 (February 15, 2020): 1505–22. http://dx.doi.org/10.1175/jcli-d-19-0222.1.

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AbstractThe heat wave in East Asia is examined by using empirical orthogonal function analysis to isolate dominant heat-wave patterns in the ground-based temperature observations over the Korean Peninsula and China and related large-scale atmospheric circulations obtained from the National Centers for Environmental Prediction–National Center for Atmospheric Research Reanalysis 1 during 1973–2012. This study focuses particularly on the interannual variability of heat waves and its decadal change. The analysis identifies two major atmospheric teleconnection patterns playing an important role in developing typical heat-wave patterns in East Asia—the Scandinavian (SCAND) and the circumglobal teleconnection (CGT) patterns, which exhibit a significant decadal change in the interannual variability in the mid-1990s. Before the mid-1990s, heat-wave occurrence was closely related to the CGT pattern, whereas the SCAND pattern is more crucial to explain heat-wave variability in the recent period. The stationary wave model experiments suggest an intensification of the SCAND pattern in the recent period driven by an increase in land–atmosphere interaction over Eurasia and decadal change in the dominant heat-wave patterns in East Asia.

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Kubát, Jiří. "NLTE Model Atmospheres of Irradiated Stars in B Binaries." International Astronomical Union Colloquium 175 (2000): 705–8. http://dx.doi.org/10.1017/s0252921100056797.

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AbstractModel atmospheres of B stars irradiated by their companion are calculated using our model atmosphere computer code under the assumption of hydrostatic, radiative, and statistical equilibrium (NLTE). The external source of radiation (a hot white dwarf) is able to change the temperature structure of the outer atmospheric layers of B stars significantly. The changes of the temperature structure cause changes in the profiles of some lines, especially in those of hydrogen.

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Laguë, Marysa M., Gordon B. Bonan, and Abigail L. S. Swann. "Separating the Impact of Individual Land Surface Properties on the Terrestrial Surface Energy Budget in both the Coupled and Uncoupled Land–Atmosphere System." Journal of Climate 32, no. 18 (August 12, 2019): 5725–44. http://dx.doi.org/10.1175/jcli-d-18-0812.1.

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Abstract Changes in the land surface can drive large responses in the atmosphere on local, regional, and global scales. Surface properties control the partitioning of energy within the surface energy budget to fluxes of shortwave and longwave radiation, sensible and latent heat, and ground heat storage. Changes in surface energy fluxes can impact the atmosphere across scales through changes in temperature, cloud cover, and large-scale atmospheric circulation. We test the sensitivity of the atmosphere to global changes in three land surface properties: albedo, evaporative resistance, and surface roughness. We show the impact of changing these surface properties differs drastically between simulations run with an offline land model, compared to coupled land–atmosphere simulations that allow for atmospheric feedbacks associated with land–atmosphere coupling. Atmospheric feedbacks play a critical role in defining the temperature response to changes in albedo and evaporative resistance, particularly in the extratropics. More than 50% of the surface temperature response to changing albedo comes from atmospheric feedbacks in over 80% of land areas. In some regions, cloud feedbacks in response to increased evaporative resistance result in nearly 1 K of additional surface warming. In contrast, the magnitude of surface temperature responses to changes in vegetation height are comparable between offline and coupled simulations. We improve our fundamental understanding of how and why changes in vegetation cover drive responses in the atmosphere, and develop understanding of the role of individual land surface properties in controlling climate across spatial scales—critical to understanding the effects of land-use change on Earth’s climate.

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Stauffer, B., H. Oeschger, and J. Schwander. "Changes Of Atmospheric Methane Concentration Parallel To Climatic Changes." Annals of Glaciology 14 (1990): 359. http://dx.doi.org/10.1017/s0260305500009368.

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Measurements on ice-core samples showed that atmospheric methane concentration changed with the large climatic cycles during the last two glaciations (Stauffer and others, 1988; Raynaud and others, 1988). The methane concentration is lower in cold periods and higher in warm periods. In this paper we discuss the results of CH4 measurements of samples from periods of minor climatic change, like the climatic optimum 8000 years B.P. and the Younger Dryas period about 10 000 to 11 000 years B.P.. The data are interpreted in terms of the present understanding of methane sources and sinks.

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Stauffer, B., H. Oeschger, and J. Schwander. "Changes Of Atmospheric Methane Concentration Parallel To Climatic Changes." Annals of Glaciology 14 (1990): 359. http://dx.doi.org/10.3189/s0260305500009368.

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Measurements on ice-core samples showed that atmospheric methane concentration changed with the large climatic cycles during the last two glaciations (Stauffer and others, 1988; Raynaud and others, 1988). The methane concentration is lower in cold periods and higher in warm periods. In this paper we discuss the results of CH4 measurements of samples from periods of minor climatic change, like the climatic optimum 8000 years B.P. and the Younger Dryas period about 10 000 to 11 000 years B.P.. The data are interpreted in terms of the present understanding of methane sources and sinks.

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11

Faxon, C. B., and D. T. Allen. "Chlorine chemistry in urban atmospheres: a review." Environmental Chemistry 10, no. 3 (2013): 221. http://dx.doi.org/10.1071/en13026.

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Environmental context Atmospheric chlorine radicals can affect the chemical composition of the atmosphere through numerous reactions with trace species. In urban atmospheres, the reactions of chlorine radicals can lead to effects such as increases in ozone production, thus degrading local and regional air quality. This review summarises the current understanding of atmospheric chlorine chemistry in urban environments and identifies key unresolved issues. Abstract Gas phase chlorine radicals (Cl•), when present in the atmosphere, react by mechanisms analogous to those of the hydroxyl radical (OH•). However, the rates of the Cl•-initiated reactions are often much faster than the corresponding OH• reactions. The effects of the atmospheric reactions of Cl• within urban environments include the oxidation of volatile organic compounds and increases in ozone production rates. Although concentrations of chlorine radicals are typically low compared to other atmospheric radicals, the relatively rapid rates of the reactions associated with this species lead to observable changes in air quality. This is particularly evident in the case of chlorine radical-induced localised increases in ozone concentrations. This review covers five aspects of atmospheric chlorine chemistry: (1) gas phase reactions; (2) heterogeneous and multi-phase reactions; (3) observational evidence of chlorine species in urban atmospheres; (4) regional modelling studies and (5) areas of uncertainty in the current state of knowledge.

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12

Mazzarella, Adriano. "Solar Forcing of Changes in Atmospheric Circulation, Earth's Rotation and Climate." Open Atmospheric Science Journal 2, no. 1 (September 18, 2008): 181–84. http://dx.doi.org/10.2174/1874282300802010181.

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Cross analysis of available historical series of solar wind turbulence, atmospheric circulation, Earth’s rotation and sea surface temperature, when smoothed from the secular trend and periods shorter than 23 years, allowed a cascade climatological model to be set up that integrates the Sun-atmosphere-Earth system as a simple unit and ties solar corpuscular output to sea surface temperature through atmospheric circulation and the Earth’s rotation. An increase in solar corpuscular activity causes a deceleration of zonal atmospheric circulation which, like a torque, causes a deceleration of the Earth’s rotation that, in turn, causes a decrease in sea surface temperature. Application of this holistic model allows us to predict a gradual decline in global warming starting from the current decade.

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Sidorenkov, N. S., and I. A. Orlov. "Atmospheric circulation epochs and climate changes." Russian Meteorology and Hydrology 33, no. 9 (September 2008): 553–59. http://dx.doi.org/10.3103/s1068373908090021.

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14

Novelli, P. C., K. A. Masarie, P. P. Tans, and P. M. Lang. "Recent Changes in Atmospheric Carbon Monoxide." Science 263, no. 5153 (March 18, 1994): 1587–90. http://dx.doi.org/10.1126/science.263.5153.1587.

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15

Seiff, Stuart R. "Atmospheric Pressure Changes and the Orbit." Ophthalmic Plastic & Reconstructive Surgery 18, no. 4 (July 2002): 239–41. http://dx.doi.org/10.1097/00002341-200207000-00001.

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16

Holzer, Mark, and George J. Boer. "Simulated Changes in Atmospheric Transport Climate." Journal of Climate 14, no. 23 (December 2001): 4398–420. http://dx.doi.org/10.1175/1520-0442(2001)014<4398:sciatc>2.0.co;2.

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17

Balcerak, Ernie. "Observing changes in atmospheric heat content." Eos, Transactions American Geophysical Union 92, no. 43 (October 25, 2011): 384. http://dx.doi.org/10.1029/2011eo430011.

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K, Charan Kumar. "Study of Atmospheric Instabilities through Radioactivity." Mapana - Journal of Sciences 14, no. 1 (July 20, 2017): 15–23. http://dx.doi.org/10.12723/mjs.32.3.

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Radon and its progeny concentration are measured at 1m height from surface of Earth in the premises of National Atmospheric Research Laboratory, Gadanki to observe the changes in activity concentration of radon particularly during instabilities that are occurring in the atmosphere. The measurements were carried out using AlphaGUARD and Alpha Progeny Meter for the measurement of radon and its progenies, respectively. It has been observed that, the changes in daily and weekly atmospheric radon levels are related to the stability or turbulence of the lower troposphere. The analysis reveals that from sunny windless days indicates growth and dissolution of the inversion layer. The study of radon concentrations during several atmospheric instabilities including period during Nilam cyclone, has shown interesting features, which are correlated with the conditions of stability or turbulence in the atmosphere.

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Byrne, Michael P., and Tapio Schneider. "Atmospheric Dynamics Feedback: Concept, Simulations, and Climate Implications." Journal of Climate 31, no. 8 (March 26, 2018): 3249–64. http://dx.doi.org/10.1175/jcli-d-17-0470.1.

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AbstractThe regional climate response to radiative forcing is largely controlled by changes in the atmospheric circulation. It has been suggested that global climate sensitivity also depends on the circulation response, an effect called the “atmospheric dynamics feedback.” Using a technique to isolate the influence of changes in atmospheric circulation on top-of-the-atmosphere radiation, the authors calculate the atmospheric dynamics feedback in coupled climate models. Large-scale circulation changes contribute substantially to all-sky and cloud feedbacks in the tropics but are relatively less important at higher latitudes. Globally averaged, the atmospheric dynamics feedback is positive and amplifies the near-surface temperature response to climate change by an average of 8% in simulations with coupled models. A constraint related to the atmospheric mass budget results in the dynamics feedback being small on large scales relative to feedbacks associated with thermodynamic processes. Idealized-forcing simulations suggest that circulation changes at high latitudes are potentially more effective at influencing global temperature than circulation changes at low latitudes, and the implications for past and future climate change are discussed.

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Russak, Vivi, Anne Joeveer, and Ain Kallis. "Der Transmissionsgrad der Atmosphäre und seine langfristige Veränderung in Estland." Meteorologische Zeitschrift 6, no. 3 (July 4, 1997): 137–41. http://dx.doi.org/10.1127/metz/6/1997/137.

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Gupta, Mohan, Stanley Tyler, and Ralph Cicerone. "Modeling atmospheric δ13CH4and the causes of recent changes in atmospheric CH4amounts." Journal of Geophysical Research: Atmospheres 101, no. D17 (October 1, 1996): 22923–32. http://dx.doi.org/10.1029/96jd02386.

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Roldugin, V. C., and B. A. Tinsley. "Atmospheric transparency changes associated with solar wind-induced atmospheric electricity variations." Journal of Atmospheric and Solar-Terrestrial Physics 66, no. 13-14 (September 2004): 1143–49. http://dx.doi.org/10.1016/j.jastp.2004.05.006.

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Changnon, Stanley A. "Historical Atmospheric Transmission Changes and Changes in Midwestern Air Pollution." Bulletin of the American Meteorological Society 68, no. 5 (May 1987): 477–80. http://dx.doi.org/10.1175/1520-0477(1987)068<0477:hatcac>2.0.co;2.

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Yanchukovsky, Valery. "MUON INTENSITY VARIATIONS AND ATMOSPHERIC TEMPERATURE." Solnechno-Zemnaya Fizika 6, no. 1 (March 30, 2020): 134–41. http://dx.doi.org/10.12737/szf-61202013.

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Muons in the atmosphere are formed during the decay of pions resulting from nuclear interactions of cosmic rays with nuclei of air atoms. The resulting muons are also unstable particles with a short lifetime. Therefore, not all of them reach the level of observation in the atmosphere. When the atmospheric temperature changes, the distance to the observation level changes too, thus leading to variations in the intensity of muons of temperature origin. These variations, caused by atmospheric temperature variations, are superimposed on continuous observations of muon telescopes. Their exclusion is, therefore, extremely necessary, especially in the data from modern muon telescopes whose statistical accuracy is very high. The contribution of various atmospheric layers to the total temperature effect is not the same for muons. This contribution is characterized by the distribution of the density of temperature coefficients for muons in the atmosphere. Using this distribution and the continuous intensity observations from the muon telescope in Novosibirsk, the inverse problem has been solved, from the solution of which the atmospheric temperature variations over a long period from 2004 to 2011 have been found. The results obtained are compared with aerological sounding data.

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Yanchukovsky, Valery. "MUON INTENSITY VARIATIONS AND ATMOSPHERIC TEMPERATURE." Solar-Terrestrial Physics 6, no. 1 (April 1, 2020): 108–15. http://dx.doi.org/10.12737/stp-61202013.

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Muons in the atmosphere are formed during the decay of pions resulting from nuclear interactions of cosmic rays with nuclei of air atoms. The resulting muons are also unstable particles with a short lifetime. Therefore, not all of them reach the level of observation in the atmosphere. When the atmospheric temperature changes, the distance to the observation level changes too, thus leading to variations in the intensity of muons of temperature origin. These variations, caused by atmospheric temperature variations, are superimposed on continuous observations of muon telescopes. Their exclusion is, therefore, extremely necessary, especially in the data from modern muon telescopes whose statistical accuracy is very high. The contribution of various atmospheric layers to the total temperature effect is not the same for muons. This contribution is characterized by the distribution of the density of temperature coefficients for muons in the atmosphere. Using this distribution and the continuous intensity observations from the muon telescope in Novosibirsk, the inverse problem has been solved, from the solution of which the atmospheric temperature variations over a long period from 2004 to 2011 have been found. The results obtained are compared with aerological sounding data.

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Jiří, Vrtiška, Křeček Josef, and Tognetti Roberto. "Indication of environmental changes in mountain catchments by dendroclimatology." Soil and Water Research 13, No. 4 (October 18, 2018): 208–17. http://dx.doi.org/10.17221/199/2017-swr.

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In the Czech Republic, mountain watersheds are mostly forested with dominant Norway spruce (Picea abies) plantations. The aim of this paper is to analyse changes in radial growth and xylem anatomy of Norway spruce trees in the upper plain of the Jizera Mountains, related to changes in climate (air temperature, precipitation), air pollution and acid atmospheric deposition. Data of two neighbouring climate stations were used to detect trends in air temperatures and precipitation. At elevations of 745–1060 m a.s.l., the ring-width growth was significantly affected by mean annual temperature, while impacts of elevation and precipitation were not significant. In the period 1975–1995, the detected drop in tree radial growth (ca 60% of the normal period, prior to the peak of acid atmospheric deposition) corresponded to the increase in atmospheric SO<sub>2</sub> concentrations and acid atmospheric deposition. The number of cells in tree rings decreased by ca 30–40% in comparison with the normal period, but the mean size of cells did not change significantly. In the last 20 years, increasing radial growth has been detected simultaneously with rising air temperature, and density of cells decreased by 30% in early wood, and by 10% in late wood, increasing the total number of cells in tree rings by ca 10% in comparison with the normal period. Integrated effects of climate and non-climate variables on the variation of tree radial growth in the Jizera Mountains reflected the legacy of acid atmospheric deposition in the forest ecosystem.

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Jackman, C. H., D. R. Marsh, D. E. Kinnison, C. J. Mertens, and E. L. Fleming. "Atmospheric changes caused by galactic cosmic rays over the period 1960–2010." Atmospheric Chemistry and Physics Discussions 15, no. 23 (December 2, 2015): 33931–66. http://dx.doi.org/10.5194/acpd-15-33931-2015.

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Abstract. The Specified Dynamics version of the Whole Atmosphere Community Climate Model (SD-WACCM) and the Goddard Space Flight Center two-dimensional (GSFC 2-D) models are used to investigate the effect of galactic cosmic rays (GCRs) on the atmosphere over the 1960–2010 time period. The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) computation of the GCR-caused ionization rates are used in these simulations. GCR-caused maximum NOx increases of 4–15 % are computed in the Southern polar troposphere with associated ozone increases of 1–2 %. NOx increases of ∼ 1–6 % are calculated for the lower stratosphere with associated ozone decreases of 0.2–1 %. The primary impact of GCRs on ozone was due to their production of NOx. The impact of GCRs varies with the atmospheric chlorine loading, sulfate aerosol loading, and solar cycle variation. Because of the interference between the NOx and ClOx ozone loss cycles (e.g., the ClO + NO2 + M → ClONO2 + M reaction) and the change in the importance of ClOx in the ozone budget, GCRs cause larger atmospheric impacts with less chlorine loading. GCRs also cause larger atmospheric impacts with less sulfate aerosol loading and for years closer to solar minimum. GCR-caused decreases of annual average global total ozone (AAGTO) were computed to be 0.2 % or less with GCR-caused tropospheric column ozone increases of 0.08 % or less and GCR-caused stratospheric column ozone decreases of 0.23 % or less. Although these computed ozone impacts are small, GCRs provide a natural influence on ozone and need to be quantified over long time periods.

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Kubyshkina, Daria, Aline A. Vidotto, Luca Fossati, and Eoin Farrell. "Coupling thermal evolution of planets and hydrodynamic atmospheric escape in mesa." Monthly Notices of the Royal Astronomical Society 499, no. 1 (September 15, 2020): 77–88. http://dx.doi.org/10.1093/mnras/staa2815.

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ABSTRACT The long-term evolution of hydrogen-dominated atmospheres of sub-Neptune-like planets is mostly controlled to by two factors: a slow dissipation of the gravitational energy acquired at the formation (known as thermal evolution) and atmospheric mass-loss. Here, we use mesa to self-consistently couple the thermal evolution model of lower atmospheres with a realistic hydrodynamical atmospheric evaporation prescription. To outline the main features of such coupling, we simulate planets with a range of core masses (5–20 M⊕) and initial atmospheric mass fractions (0.5–30 per cent), orbiting a solar-like star at 0.1 au. In addition to our computed evolutionary tracks, we also study the stability of planetary atmospheres, showing that the atmospheres of light planets can be completely removed within 1 Gyr and that compact atmospheres have a better survival rate. From a detailed comparison between our results and the output of the previous-generation models, we show that coupling between thermal evolution and atmospheric evaporation considerably affects the thermal state of atmospheres for low-mass planets and, consequently, changes the relationship between atmospheric mass fraction and planetary parameters. We, therefore, conclude that self-consistent consideration of the thermal evolution and atmospheric evaporation is of crucial importance for evolutionary modelling and a better characterization of planetary atmospheres. From our simulations, we derive an analytical expression between planetary radius and atmospheric mass fraction at different ages. In particular, we find that, for a given observed planetary radius, the predicted atmospheric mass fraction changes as age0.11.

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Pendergrass, Angeline G., and Dennis L. Hartmann. "The Atmospheric Energy Constraint on Global-Mean Precipitation Change." Journal of Climate 27, no. 2 (January 15, 2014): 757–68. http://dx.doi.org/10.1175/jcli-d-13-00163.1.

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Abstract Models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) robustly predict that the rate of increase in global-mean precipitation with global-mean surface temperature increase is much less than the rate of increase of water vapor. The goal of this paper is to explain in detail the mechanisms by which precipitation increase is constrained by radiative cooling. Changes in clear-sky atmospheric radiative cooling resulting from changes in temperature and humidity in global warming simulations are in good agreement with the multimodel, global-mean precipitation increase projected by GCMs (~1.1 W m−2 K−1). In an atmosphere with fixed specific humidity, radiative cooling from the top of the atmosphere (TOA) increases in response to a uniform temperature increase of the surface and atmosphere, while atmospheric cooling by exchange with the surface decreases because the upward emission of longwave radiation from the surface increases more than the downward longwave radiation from the atmosphere. When a fixed relative humidity (RH) assumption is made, however, uniform warming causes a much smaller increase of cooling at the TOA, and the surface contribution reverses to an increase in net cooling rate due to increased downward emission from water vapor. Sensitivity of precipitation changes to lapse rate changes is modest when RH is fixed. Carbon dioxide reduces TOA emission with only weak effects on surface fluxes, and thus suppresses precipitation. The net atmospheric cooling response and thereby the precipitation response to CO2-induced warming at fixed RH are mostly contributed by changes in surface fluxes. The role of clouds is discussed. Intermodel spread in the rate of precipitation increase across the CMIP5 simulations is attributed to differences in the atmospheric cooling.

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Alley, R. B., R. C. Finkel, K. Nishiizumi, S. Anandakrishnan, C. A. Shuman, G. Mershon, G. A. Zielinski, and P. A. Mayewski. "Changes in continental and sea-salt atmospheric loadings in central Greenland during the most recent deglaciation: model-based estimates." Journal of Glaciology 41, no. 139 (1995): 503–14. http://dx.doi.org/10.1017/s0022143000034845.

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AbstractBy fitting a very simple atmospheric impurity model to high-resolution data on ice accumulation and contaminant fluxes in the GISP2 ice core, we have estimated changes in the atmospheric concentrations of soluble major ions, insoluble particulates and10Be during the transition from glacial to Holocene conditions. For many species, changes in concentration in the ice typically overestimate atmospheric changes, and changes in flux to the ice typically underestimate atmospheric changes, because times of increased atmospheric contaminant loading are also times of reduced snowfall. The model interpolates between the flux and concentration records by explicitly allowing for wet- and dry-deposition processes. Compared to the warm Preboreal that followed, we estimate that the atmosphere over Greenland sampled by snow accumulated during the Younger Dryas cold event contained on average four–seven times the insoluble particulates and nearly seven times the soluble calcium derived from continental sources, and about three times the sea salt but only slightly more cosmogenic10Be.

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Alley, R. B., R. C. Finkel, K. Nishiizumi, S. Anandakrishnan, C. A. Shuman, G. Mershon, G. A. Zielinski, and P. A. Mayewski. "Changes in continental and sea-salt atmospheric loadings in central Greenland during the most recent deglaciation: model-based estimates." Journal of Glaciology 41, no. 139 (1995): 503–14. http://dx.doi.org/10.3189/s0022143000034845.

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AbstractBy fitting a very simple atmospheric impurity model to high-resolution data on ice accumulation and contaminant fluxes in the GISP2 ice core, we have estimated changes in the atmospheric concentrations of soluble major ions, insoluble particulates and 10Be during the transition from glacial to Holocene conditions. For many species, changes in concentration in the ice typically overestimate atmospheric changes, and changes in flux to the ice typically underestimate atmospheric changes, because times of increased atmospheric contaminant loading are also times of reduced snowfall. The model interpolates between the flux and concentration records by explicitly allowing for wet- and dry-deposition processes. Compared to the warm Preboreal that followed, we estimate that the atmosphere over Greenland sampled by snow accumulated during the Younger Dryas cold event contained on average four–seven times the insoluble particulates and nearly seven times the soluble calcium derived from continental sources, and about three times the sea salt but only slightly more cosmogenic 10Be.

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Hsu, Yang-Hui, Chia Chou, and Kuo-Yen Wei. "Land–Ocean Asymmetry of Tropical Precipitation Changes in the Mid-Holocene." Journal of Climate 23, no. 15 (August 1, 2010): 4133–51. http://dx.doi.org/10.1175/2010jcli3392.1.

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Abstract A series of model experiments were conducted using an intermediate ocean–atmosphere–land model for a better understanding of a distinct land–sea asymmetry in tropical precipitation differences between the mid-Holocene and preindustrial climates. In austral (boreal) summer, most reduced (enhanced) precipitation occurs over continental convective regions, while most enhanced (reduced) precipitation occurs over oceanic convection zones. This land–sea asymmetry of tropical precipitation is particularly clear in austral summer. During the mid-Holocene, the solar forcing presents both spatial and seasonal asymmetric patterns. While the boreal summer insolation is stronger at high latitudes of the Northern Hemisphere in the mid-Holocene than at present, the austral summer insolation is weaker with a more spatially symmetric distribution about the equator. Because of the slow response time of the ocean to forcing, the direct insolation forcing of the current season is cancelled by the ocean memory of an earlier insolation forcing, which in the case of the mid-Holocene is opposite to the current season insolation forcing. As a result, tropical sea surface temperature variation, as well as the tropical atmospheric temperature and moisture changes, is small, which gives rise to a different precipitation response from under the condition of stronger atmospheric temperature and moisture changes, such as in the case of postindustrial global warming induced by an increased concentration of atmospheric greenhouse gases. Thus, the cancellation between the direct and memory effects of the seasonally asymmetric insolation forcing leaves the net energy into the atmosphere to be responsible for the land–sea asymmetry of tropical precipitation changes.

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Totz, Sonja, Stefan Petri, Jascha Lehmann, Erik Peukert, and Dim Coumou. "Exploring the sensitivity of Northern Hemisphere atmospheric circulation to different surface temperature forcing using a statistical–dynamical atmospheric model." Nonlinear Processes in Geophysics 26, no. 1 (February 18, 2019): 1–12. http://dx.doi.org/10.5194/npg-26-1-2019.

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Abstract. Climate and weather conditions in the mid-latitudes are strongly driven by the large-scale atmosphere circulation. Observational data indicate that important components of the large-scale circulation have changed in recent decades, including the strength and the width of the Hadley cell, jets, storm tracks and planetary waves. Here, we use a new statistical–dynamical atmosphere model (SDAM) to test the individual sensitivities of the large-scale atmospheric circulation to changes in the zonal temperature gradient, meridional temperature gradient and global-mean temperature. We analyze the Northern Hemisphere Hadley circulation, jet streams, storm tracks and planetary waves by systematically altering the zonal temperature asymmetry, the meridional temperature gradient and the global-mean temperature. Our results show that the strength of the Hadley cell, storm tracks and jet streams depend, in terms of relative changes, almost linearly on both the global-mean temperature and the meridional temperature gradient, whereas the zonal temperature asymmetry has little or no influence. The magnitude of planetary waves is affected by all three temperature components, as expected from theoretical dynamical considerations. The width of the Hadley cell behaves nonlinearly with respect to all three temperature components in the SDAM. Moreover, some of these observed large-scale atmospheric changes are expected from dynamical equations and are therefore an important part of model validation.

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Omori, Y., Y. Yasuoka, H. Nagahama, Y. Kawada, T. Ishikawa, S. Tokonami, and M. Shinogi. "Anomalous radon emanation linked to preseismic electromagnetic phenomena." Natural Hazards and Earth System Sciences 7, no. 5 (October 26, 2007): 629–35. http://dx.doi.org/10.5194/nhess-7-629-2007.

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Abstract. Anomalous emanation of radon (222Rn) was observed preceding large earthquakes and is considered to be linked to preseismic electromagnetic phenomena (e.g. great changes of atmospheric electric field and ionospheric disturbances). Here we analyze atmospheric radon concentration and estimate changes of electrical conditions in atmosphere due to preseismic radon anomaly. The increase of radon emanation obeys crustal damage evolution, following a power-law of time-to-earthquake. Moreover, the radon emanation decreases the atmospheric electric field by 40%, besides influencing the maximum strength of atmospheric electric field by 104–105 V/m enough to trigger ionospheric disturbances. These changes are within the ranges observed or explaining electromagnetic phenomena associated with large earthquakes.

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Jackman, Charles H., Daniel R. Marsh, Douglas E. Kinnison, Christopher J. Mertens, and Eric L. Fleming. "Atmospheric changes caused by galactic cosmic rays over the period 1960–2010." Atmospheric Chemistry and Physics 16, no. 9 (May 13, 2016): 5853–66. http://dx.doi.org/10.5194/acp-16-5853-2016.

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Abstract. The Specified Dynamics version of the Whole Atmosphere Community Climate Model (SD-WACCM) and the Goddard Space Flight Center two-dimensional (GSFC 2-D) models are used to investigate the effect of galactic cosmic rays (GCRs) on the atmosphere over the 1960–2010 time period. The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) computation of the GCR-caused ionization rates are used in these simulations. GCR-caused maximum NOx increases of 4–15 % are computed in the Southern polar troposphere with associated ozone increases of 1–2 %. NOx increases of ∼ 1–6 % are calculated for the lower stratosphere with associated ozone decreases of 0.2–1 %. The primary impact of GCRs on ozone was due to their production of NOx. The impact of GCRs varies with the atmospheric chlorine loading, sulfate aerosol loading, and solar cycle variation. Because of the interference between the NOx and ClOx ozone loss cycles (e.g., the ClO + NO2+ M → ClONO2+ M reaction) and the change in the importance of ClOx in the ozone budget, GCRs cause larger atmospheric impacts with less chlorine loading. GCRs also cause larger atmospheric impacts with less sulfate aerosol loading and for years closer to solar minimum. GCR-caused decreases of annual average global total ozone (AAGTO) were computed to be 0.2 % or less with GCR-caused column ozone increases between 1000 and 100 hPa of 0.08 % or less and GCR-caused column ozone decreases between 100 and 1 hPa of 0.23 % or less. Although these computed ozone impacts are small, GCRs provide a natural influence on ozone and need to be quantified over long time periods. This result serves as a lower limit because of the use of the ionization model NAIRAS/HZETRN which underestimates the ion production by neglecting electromagnetic and muon branches of the cosmic ray induced cascade. This will be corrected in future works.

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Lambert, G., P. Monfray, B. Ardouin, G. Bonsang, A. Gaudry, V. Kazan, and G. Polian. "Year-to-year changes in atmospheric CO2." Tellus B: Chemical and Physical Meteorology 47, no. 1-2 (January 1995): 53–55. http://dx.doi.org/10.3402/tellusb.v47i1-2.16000.

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Dlugokencky, Edward J., Euan G. Nisbet, Rebecca Fisher, and David Lowry. "Global atmospheric methane: budget, changes and dangers." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1943 (May 28, 2011): 2058–72. http://dx.doi.org/10.1098/rsta.2010.0341.

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A factor of 2.5 increase in the global abundance of atmospheric methane (CH 4 ) since 1750 contributes 0.5 Wm −2 to total direct radiative forcing by long-lived greenhouse gases (2.77 Wm −2 in 2009), while its role in atmospheric chemistry adds another approximately 0.2 Wm −2 of indirect forcing. Since CH 4 has a relatively short lifetime and it is very close to a steady state, reductions in its emissions would quickly benefit climate. Sensible emission mitigation strategies require quantitative understanding of CH 4 ’s budget of emissions and sinks. Atmospheric observations of CH 4 abundance and its rate of increase, combined with an estimate of the CH 4 lifetime, constrain total global CH 4 emissions to between 500 and 600 Tg CH 4 yr −1 . While total global emissions are constrained reasonably well, estimates of emissions by source sector vary by up to a factor of 2. Current observation networks are suitable to constrain emissions at large scales (e.g. global) but not at the regional to national scales necessary to verify emission reductions under emissions trading schemes. Improved constraints on the global CH 4 budget and its break down of emissions by source sector and country will come from an enhanced observation network for CH 4 abundance and its isotopic composition ( δ 13 C, δ D (D= 2 H) and δ 14 C). Isotopic measurements are a valuable tool in distinguishing among various sources that contribute emissions to an air parcel, once fractionation by loss processes is accounted for. Isotopic measurements are especially useful at regional scales where signals are larger. Reducing emissions from many anthropogenic source sectors is cost-effective, but these gains may be cancelled, in part, by increasing emissions related to economic development in many parts of the world. An observation network that can quantitatively assess these changing emissions, both positive and negative, is required, especially in the context of emissions trading schemes.

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Monge, M. E., B. D'Anna, L. Mazri, A. Giroir-Fendler, M. Ammann, D. J. Donaldson, and C. George. "Light changes the atmospheric reactivity of soot." Proceedings of the National Academy of Sciences 107, no. 15 (January 6, 2010): 6605–9. http://dx.doi.org/10.1073/pnas.0908341107.

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39

Jouzel, Jean, Georg Hoffmann, Frédéric Parrenin, and Claire Waelbroeck. "Atmospheric oxygen 18 and sea-level changes." Quaternary Science Reviews 21, no. 1-3 (January 2002): 307–14. http://dx.doi.org/10.1016/s0277-3791(01)00106-8.

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40

LAMBERT, G., P. MONFRAY, B. ARDOUIN, G. BONSANG, A. GAUDRY, V. KAZAN, and G. POLIAN. "Year-to-year changes in atmospheric CO2." Tellus B 47, no. 1-2 (February 1995): 53–55. http://dx.doi.org/10.1034/j.1600-0889.47.issue1.6.x.

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Aqramunnisah, D. A. Suriamihardja, A. H. Assegaf, and B. A. Samad. "Phase Changes in the Atmospheric Hydrology Cycle." IOP Conference Series: Earth and Environmental Science 279 (September 5, 2019): 012048. http://dx.doi.org/10.1088/1755-1315/279/1/012048.

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42

Balcerak, Ernie. "Atmospheric tides link stratosphere and ionosphere changes." Eos, Transactions American Geophysical Union 95, no. 24 (June 17, 2014): 208. http://dx.doi.org/10.1002/2014eo240008.

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43

Harrison, R. G., and K. L. Aplin. "Water vapour changes and atmospheric cluster ions." Atmospheric Research 85, no. 2 (August 2007): 199–208. http://dx.doi.org/10.1016/j.atmosres.2006.12.006.

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44

Kane, R. P., and E. R. de Paula. "Atmospheric CO2 changes at Mauna Loa, Hawaii." Journal of Atmospheric and Terrestrial Physics 58, no. 15 (November 1996): 1673–81. http://dx.doi.org/10.1016/0021-9169(95)00193-x.

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45

Harrop, Bryce E., and Dennis L. Hartmann. "The Relationship between Atmospheric Convective Radiative Effect and Net Energy Transport in the Tropical Warm Pool." Journal of Climate 28, no. 21 (October 30, 2015): 8620–33. http://dx.doi.org/10.1175/jcli-d-15-0151.1.

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Abstract Reanalysis data and radiation budget data are used to calculate the role of the atmospheric cloud radiative effect in determining the magnitude of horizontal export of energy by the tropical atmosphere. Because tropical high clouds result in net radiative heating of the atmosphere, they increase the requirement for the atmosphere to export energy from convective regions. Increases in upper-tropospheric water vapor associated with convection contribute about a fifth of the atmospheric radiative heating anomaly associated with convection. Over the warmest tropical oceans, the radiative effect of convective clouds and associated water vapor is roughly two-thirds the value of the atmospheric energy transport. Cloud radiative heating and atmospheric heat transport increase at the same rate with increasing sea surface temperature, suggesting that the increased energy export is supplied by the radiative heating associated with convective clouds. The net cloud radiative effect at the top of the atmosphere is insensitive to changes in SST over the warm pool. Principal component analysis of satellite-retrieved cloud data reveals that the insensitivity of the net cloud radiative effect to SST is the result of changes in cloud amount offsetting changes in cloud optical thickness and cloud-top height. While increasing upward motion makes the cloud radiative effect more negative, that decrease is offset by reductions in outgoing longwave radiation owing to increases in water vapor.

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46

Meerkötter, R., U. Schumann, D. R. Doelling, P. Minnis, T. Nakajima, and Y. Tsushima. "Radiative forcing by contrails." Annales Geophysicae 17, no. 8 (August 31, 1999): 1080–94. http://dx.doi.org/10.1007/s00585-999-1080-7.

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Abstract. A parametric study of the instantaneous radiative impact of contrails is presented using three different radiative transfer models for a series of model atmospheres and cloud parameters. Contrails are treated as geometrically and optically thin plane parallel homogeneous cirrus layers in a static atmosphere. The ice water content is varied as a function of ambient temperature. The model atmospheres include tropical, mid-latitude, and subarctic summer and winter atmospheres. Optically thin contrails cause a positive net forcing at top of the atmosphere. At the surface the radiative forcing is negative during daytime. The forcing increases with the optical depth and the amount of contrail cover. At the top of the atmosphere, a mean contrail cover of 0.1% with average optical depth of 0.2 to 0.5 causes about 0.01 to 0.03 Wm-2 daily mean instantaneous radiative forcing. Contrails cool the surface during the day and heat the surface during the night, and hence reduce the daily temperature amplitude. The net effect depends strongly on the daily variation of contrail cloud cover. The indirect radiative forcing due to particle changes in natural cirrus clouds may be of the same magnitude as the direct one due to additional cover.Key words. Atmospheric composition and structure (aerosols and particles) · Meteorology and atmospheric dynamics (climatology · radiative processes)

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Das, S. K., A. Taori, and A. Jayaraman. "On the role of dust storms in triggering atmospheric gravity waves observed in the middle atmosphere." Annales Geophysicae 29, no. 9 (September 27, 2011): 1647–54. http://dx.doi.org/10.5194/angeo-29-1647-2011.

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Abstract. Lower atmospheric perturbations often produce measurable effects in the middle and upper atmosphere. The present study demonstrates the response of the middle atmospheric thermal structure to the significant enhancement of the lower atmospheric heating effect caused by dust storms observed over the Thar Desert, India. Our study from multi-satellite observations of two dust storm events that occurred on 3 and 8 May 2007 suggests that dust storm events produce substantial changes in the lower atmospheric temperatures as hot spots which can become sources for gravity waves observed in the middle atmosphere.

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48

Ahn, Young Sang, Raae Jung, and Jae-Hyun Moon. "Approaches to Understand Historical Changes of Mercury in Tree Rings of Japanese Cypress in Industrial Areas." Forests 11, no. 8 (July 25, 2020): 800. http://dx.doi.org/10.3390/f11080800.

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Historical changes of mercury (Hg) concentrations in tree rings of Japanese cypress (Chamaecyparis obtusa) and the role of dendrochemistry over the last 50 years in Yeosu and Gwangyang National Industrial Complexes of South Korea were evaluated. Mercury uptake in trees were found to be bidirectional and variable depending on atmospheric Hg conditions. With low atmospheric Hg concentrations, Hg concentrations in tree rings were significantly influenced by soil Hg concentrations via roots. With high atmospheric Hg concentrations, Hg concentrations in tree rings were dominated by atmospheric Hg uptake via foliage. Patterns of Hg concentration in sampling sites were divided into: (1) a linear increase in low concentration of Hg originated from soils via roots during 1967–1977 and (2) an elevated and constant concentration with spatial variation of Hg concentration due to foliar uptake from atmosphere during 1978–2014. Between 1967 and 1977, when shrubs and vegetation senesced each year, there was an annual source of Hg in soils due to continued deposition of Hg to soil via litterfall and debris. Thus, Hg concentration was increased over time. During these periods, Hg concentrations in tree rings reflected uptakes of Hg through roots under young forest and low atmosphere Hg conditions. Whether tree rings can serve as reliable proxies for atmosphere Hg concentrations remain unclear due to Hg uptakes from soils and limits from atmosphere under low atmospheric Hg conditions. Intensified chemical plants and steel mills have continued throughout Yeosu and Gwangyang industrial areas since late 1970s, resulting in high Hg emissions. Hg concentrations in tree rings during 1978–2014 showed elevated and constant levels. In addition, tree ring Hg concentrations at study sites were increased gradually with decreasing distance from industrial areas, with a high concentration of 11.15 ng/g at the Yeosu site located the nearest to industrial areas and a low concentration of 4.34 ng/g at the Suncheon site which was the farthest away from industrial areas.

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Pylypenko, S., O. Motsyk, and L. Kozak. "Temperature changes over storms from measurements of spacecraft TIMED." Advances in Astronomy and Space Physics 6, no. 1 (2016): 50–55. http://dx.doi.org/10.17721/2227-1481.6.50-55.

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In the present work we have studied changes of mesospheric temperature over the powerful storms Wilma, Haitang, and Katrina using measurements of the space vehicle TIMED. We have found the temperature increasing at the altitude range 80-100 km. We have found the explanations for the obtained results by the dissipation of the gravity waves. Propagation of atmospheric gravity waves in a non-isothermal, windless atmosphere, with taking into account the viscosity and the thermal conductivity, has also been modelled in this work. We have determined that the maximum of amplitude of the atmospheric-gravity waves at the considered characteristics corresponds to altitudes of near 90 km (mesopause). It was found that the main factor influencing propagation and dissipation of the wave in such cases is the vertical temperature gradient. Viscosity and thermal conductivity have less influence on the wave amplitude.

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Akmaev, R. A., V. I. Fomichev, and X. Zhu. "Impact of middle-atmospheric composition changes on greenhouse cooling in the upper atmosphere." Journal of Atmospheric and Solar-Terrestrial Physics 68, no. 17 (December 2006): 1879–89. http://dx.doi.org/10.1016/j.jastp.2006.03.008.

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Journal articles on the topic 'Atmospheric changes'

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