5,251 research outputs found
Supporting Data for "Climate Sensitivity and Relative Humidity Changes in Global Storm-Resolving Model Simulations of Climate Change"
No full text<p>Code and netcdf files of processed X-SHiELD and CMIP6 simulations to reproduce the figures of Timothy M. Merlis, Kai-Yuan Cheng, Ilai Guendelman, Lucas Harris, Christopher S. Bretherton, Maximilien Bolot, Linjiong Zhou, Alex Kaltenbaugh, Spencer K. Clark, Gabriel A. Vecchi, and Stephan Fueglistaler (2024): "Climate Sensitivity and Relative Humidity Changes in Global Storm-Resolving Model Simulations of Climate Change".</p>
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Money piece by Timothy P. Agnew, chief executive officer of the Finance Author
No full textMoney piece by Timothy P. Agnew, chief executive officer of the Finance Authority of Maine, about the increased availability of credit for Maine\u27s small businesses
The General Circulation of the Tropical Atmosphere and Climate Changes
Get PDFI examine the general circulation of the tropical atmosphere and climate changes. First, the response of the zonal surface temperature gradients and zonally asymmetric tropical overturning circulations (Walker circulations) to substantial changes in the longwave optical depth of the atmosphere in an idealized general circulation model (GCM) is compared with scaling theories. Second, the response of the hydrological cycle and monsoonal Hadley circulations to changes in top-of-atmosphere insolation associated with orbital precession is examined in an idealized GCM.
Zonal surface temperature gradients and Walker circulations are examined over a wide range of climates simulated by varying the optical thickness in an idealized atmospheric GCM with a climate-invariant zonally asymmetric ocean energy flux. The tropical zonal surface temperature gradient and Walker circulation generally decrease as the climate warms in the GCM simulations. A scaling relationship based on a two-term balance in the surface energy budget accounts for the changes in the zonally asymmetric component of the GCM-simulated surface temperature gradients. A scaling estimate for the Walker circulation based on differential changes (precipitation rates and saturation specific humidity) in the hydrological cycle accounts for the GCM simulations provided locally averaged quantities are used in the estimate.
The results of atmospheric GCM simulations with varied top-of-atmosphere insolation are analyzed to constrain orbitally-forced changes in the tropical atmospheric circulations and precipitation. When the perihelion is varied between solstices, there is more annual-mean precipitation in the hemisphere in which perihelion occurs during the summer solstice. In aquaplanet simulations, this is primarily associated with thermodynamic changes: there is a correlation between the seasonal cycle of the perturbed water vapor and the seasonal cycle of the Hadley circulation convergence. The monsoonal Hadley circulation does not respond to insolation gradients in a simple manner, as the atmosphere’s energy stratification changes. An idealized continent that has a simple treatment of land surface hydrology and inhomogeneous heat capacity allows an assessment of how land-sea contrasts can mediate the response to orbital precession. In these simulations, the response of precipitation to orbital precession depends on changes in the atmospheric circulation, which strengthens when perihelion occurs in the summer of the hemisphere with the land region. The changes in atmospheric circulation are related to changes in both the top-of-atmosphere energy balance and the thermodynamic properties of the surface.</p
Tropical cyclone response to greenhouse and solar forcing
No full textThe response of tropical cyclone (TC) activity and frequency in different perturbed climates is investigated with an aquaplanet configuration of a Global Climate Model with 50-km horizontal resolution. To understand the differences between solar and carbon dioxide (CO2) forcing, the direct response to the forcing, sea surface temperature (SST) changes, and the combined response in slab-ocean model simulations are compared. The increased solar constant simulations and the 4xCO2 simulations have the same global-mean radiative forcing (about 7.7 Wm^(-2)), but the TC frequency changes are greater in magnitude for CO2 forcing than for solar forcing. Quadrupling CO2 also leads to a greater response of environmental variables that influence TC activity. TC frequency and intensity increase in a warmed climates, though not as a direct response to radiative forcing. The increase in TC activity is consistent with changes in environmental variables such as potential intensity, absolute vorticity, and convergence zone latitude, and is not accounted for by other previously discussed environmental variables such as moist entropy deficit, vertical wind shear, and vertical velocity.The direct response to radiative forcing for most of the environmental variables is opposite to the response to SST changes. The simulations have departures from linear additivity of the combined response to forcing and SST in isolation, which suggests that time-dependent SST fluctuations may need to be prescribed in fixed-SST simulations in order to better reproduce TC changes.Nous avons étudiés sur une planète d'eau, avec un modèle climatique global de 50-km de résolution horizontale, les changements induit par des perturbations climatiques sur l'activité et la fréquence des cyclones tropicaux (CT). Pour comprendre les différences entre le forçage radiatif solaire et le forçage radiatif du dioxyde de carbone (CO2), les résultats des simulations avec forçage radiatif, des simulations avec forçage radiatif et températures de surface de l'océan augmenté et les simulations avec l'océan à couche de mélange "en dalle" sont examinées. Les simulations avec la constante solaire la plus élevée (1450 Wm^(- 2)) et les simulations avec la concentration en CO2 la plus élevée (1200ppm) ont le même forçage radiatif global (environ 7,7 Wm^(- 2)), mais les résultats suggèrent que les changements de fréquence des CT sont plus influencés par le forçage radiatif du CO2 que par le forçage radiatif de la constante solaire. Quadrupler la concentration de CO2 mène à des changements plus significatif, sur les variables environnementales et sur les variations des CT, que l'augmentation de la constante solaire. La fréquence et l'intensité des CT augmentent dans un climat plus chaud sauf quand le forçage est seulement radiatif. L'augmentation de l'activitédes CT est cohérente avec les changements des variables environnementales tels que l'intensité potentielle, la vorticité absolue et la fonction de courant, mais ne parviennent pas à être expliquée par d'autres changements des variables environnementales tels que le déficit de l'entropie humide, cisaillement vertical du vent, le vent vertical. Les simulations avec forçage radiatif induisent pour la plupart des variables d'environnementales un changement opposé quand comparéaux simulations avec changement des températures de surface de l'océan. De plus, les résultats suggèrent que la dépendance temporelle des fluctuations de température de surface de l'océan devraient probablement être prescrit pour les simulations avec les températures de surfaces de l'océan fixées afin de mieux reproduire les changements des CT
Timothy Meyer serves as a contributing author for UN report
No full textAssistant Professor Timothy Meyer served as a contributing author for the United Nations Industrial Development Organization\u27s report titled Networks for Prosperity: Connecting Development Knowledge Beyond 2015. The document, which was released during November, analyzes the nexus between the global connectedness of a country and its economic success, sustainability and government effectiveness. Meyer was one of only approximately 20 academic and practical experts from around the world selected to serve as a contributor after a global call for proposals.
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Selected Contributions of Sister Mary Berenice Beck, O.S.F. to Nursing in the United States, 1923-1956
No full textby Sister M. Timothy Costello.Typescript.Thesis (M.S.N.)--Catholic University of America.Bibliography: leaves 44-47.Also available in microfilm
The Baptismal Liturgy of Theodore of Mopsuestia
No full textTimothy A. Curtin.Typescript.Thesis (S.T.D.)--Catholic University of America, 1971.Bibliography: leaves 368-393
Investigating the impact of direct effects of radiative forcing on ocean heat uptake
No full textThe ocean's response to direct atmospheric effects of increased carbon dioxide's (CO2) radiative forcing is examined. These direct effects are defined as physical climate changes that respond to forcing on a fast timescale of a few years, independent of the slower surface warming that the forcing also provokes. To evaluate how these directeffects impact ocean heat uptake (OHU), output of atmospheric climate simulations are used to force an ocean-only model with comprehensive boundary conditions. Perturbation simulations with the prescribed response to a quadrupling of atmospheric CO2 include altered surface winds, freshwater fluxes, and downwelling shortwave radiation boundary conditions. The perturbation simulations show that the intensification and poleward shift of surface winds, particularly in the Southern Ocean, strengthen the overturning circulation both in the Pacific and Atlantic Oceans. This, in turn, has a cooling effect on the global ocean at shallow depths. A two-layer energy balance model designed to capture transient, global-mean climate change, is adapted to accommodate the altered ocean heat uptake from direct effects. To assess the relative significance of direct effects on OHU, additional simulations are conducted by perturbing the ocean-only model with temperature-dependent changes in atmospheric fields. The total atmospheric response to radiative forcing is decomposed between the direct response and the temperature-dependent response using results from coupled atmosphere-ocean climate simulations. Perturbations to the atmospheric forcing parameters evolve as the ocean model's global-mean sea surface temperature increases which mimics the time-dependence of the response to increased CO2 in coupled models. Together, the results build understanding of how ocean heat uptake is impacted by the atmospheric response to CO2 radiative forcing.La réponse de l'océan aux effets atmosphériques directs du forçage radiatif lie à une augmentation de dioxyde de carbone (CO2) est examiné. Ces effets directs sont dénis comme les changements climatiques du au forçage radiatif qui ont lieu sur une échelle de temps de quelques années, indépendamment du réchauffement en surface qui se passe plus lentement. Afin d'évaluer comment ces effets directs affectent l'absorption de la chaleur par l'océan, des résultats de simulations climatiques atmosphériques sont utilisés comme forçage dans un modèle océanique avec un ensemble de conditions aux limites. Les simulations de l'océan qui ont comme forçage le changement dans l'atmosphère du a un quadruplement du CO2 montrent des changements dans les vents de surface, dans le flux d'eau fraiche et dans le rayonnement solaire reçu. Ces simulations montrent que l'intensification et la migration vers les pôles des vents de surface renforcent la circulation méridienne de retournement dans les océans atlantique et pacifique. Ceci a un effet de refroidissement sur les eaux de surface de l'océan. Un modèle d'équilibre énergétique a deux niveaux conçu pour l'analyse des changements climatiques transitoires est adapté en incluant la modification de l'absorption de la chaleur par l'océan à cause des effets directs de l'atmosphère. An d'évaluer l'effet relatif des effets directs de l'atmosphère sur l'absorption de la chaleur par l'océan, des simulations additionnelles sont menées en appliquant une perturbation au modèle océanique avec les changements atmosphériques qui dépendent de la température. La réaction atmosphérique totale au forçage radiatif est décomposée entre la réaction directe et la réaction qui dépend de la température en utilisant des résultats issus d'un modèle climatique couple. Les paramètres du forçage atmosphérique évoluent en fonction de l'évolution de la moyenne globale de la température de surface, qui augmente en réponse à l'augmentation de CO2. Ces résultats permettent de comprendre comment l'absorption de la chaleur par l'océan est affectée par la réaction atmosphérique a un forçage radiatif lie à une augmentation de CO2
Five minutes with Timothy Gowers: “academics can publish journals of the highest quality without a commercial entity”
Get PDFFields Medal-winning Cambridge mathematician Sir Timothy Gowers and a team of colleagues have recently launched a new editor-owned Open Access (OA) journal for mathematics. Discrete Analysis is an arXiv overlay journal, which means articles are submitted and hosted via the preprint server arXiv first. The journal coordinates peer-review and publishes via Scholastica with no cost to reader or author. Gowers reflects here on his vision for the future of editor-owned journals
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