196,072 research outputs found
Dataset associated with "Three flavors of radiative feedbacks and their implications for estimating Equilibrium Climate Sensitivity"
No full textThese are numerical data for all plots shown in the paper:
1) The LongRunMIP output of global and annual mean “tas” and “netTOA” for the models CCSM3 (abrupt2x and aburpt4x), CESM (abrupt2x and abrupt4x), CNRMCM61 (abrupt2x and abrupt4x), ECHAM5MPIOM (abrupt4x), GISSE2R (abrupt4x), HadCM3L (abrupt2x and abrupt4x), HadGEM2 (abrupt4x), IPSLCM5A (abrupt4x), MPIESM11 (abrupt4x), MPIESM12 (abrupt2x and abrupt4x)
2) ECSvalues.txt contain the ECS estimates as shown in Fig. 2 in the paper. ECSvalues_Bayesianfit.txt contain the ECS estimate with uncertainty ranges of the energy balance model as presented in Proistosescu et al. 2017.
3) Model output of global and annual mean “tas” and “netTOA” for the model CESM 1.0.4, as shown in Fig. 1. "cesmtempfit*.nc” are the splines fitted to the “tas” output for converting the differential feedback parameter from temperature to time, as detailed in Rugenstein et al. 2016.The realization that atmospheric radiative feedbacks depend on the underlying patterns of surface warming and global temperature, and thus, change over time has led to an ignition of feedback definitions and methods to estimate equilibrium climate sensitivity. We contrast three flavors of radiative feedbacks -- equilibrium, effective, and differential feedback -- and discuss their physical interpretations and applications. We show that their values at any given time can differ more than 1Wm-2K-1 and their implied equilibrium or effective climate sensitivity can differ several degrees. With ten (quasi) equilibrated climate models, we show that 400 years might be enough to estimate the true equilibrium climate sensitivity with a 5% error and a simple regression method utilizing the differential feedback parameter. We argue that a community-wide agreement on the interpretation of the different feedback definitions would advance the quest to narrow the estimate of climate sensitivity
Dataset associated with "El Niño–Southern Oscillation (ENSO) predictability in equilibrated warmer climates"
No full textThe Niño 3.4 index calculated from the LongRunMIP outputs of global and annual TAS in seven models (CCSM3, CESM104, CNRMCM61, GISSE2R, HadCM3L, IPSLCM5A, and MPIESM12) with two forcing levels (control and abrupt4x). The LongRunMIP outputs are gained from an archive described in Rugenstein et al. 2019. All simulations used here are millennial-length long. Predictability.txt and characteristics.txt contain the changes of ENSO characteristics (frequency and events' duration) and ENSO predictability (6-month averaged accuracy). The explained variance of ENSO predictability by ENSO characteristics in the observations, control simulations, and changes between control and abrupt4x simulations.Institute of Oceanography, The Center for Earth System Research and Sustainability, Universität Hamburg, Hamburg, Germany; Department of Atmospheric Science, Colorado State University, Fort Collins, CO, USA.Responses of El Niño-Southern Oscillation (ENSO) to global warming remain uncertain, which challenges ENSO forecasts in a warming climate. We investigate changes in ENSO characteristics and predictability in idealized simulations with quadrupled CO2 forcing from seven general circulation models. Comparing the warmer climate to control simulations, ENSO variability weakens, with the neutral state lasts longer, while active ENSO states last shorter and skew to favor the La Niña state. Six-month persistence-assessed ENSO predictability slightly reduces in five models and increases in two models under the warming condition. While the overall changes in ENSO predictability are insignificant, we find significant relationships between changes in predictability and intensity, duration and skewness of the three individual ENSO states. The maximal contribution to changes in the predictability of El Niño, La Niña and neutral states stems from changes in skewness and events' duration. Our findings show that a robust and significant decrease in ENSO characteristics does not imply a similar change in ENSO predictability in a warmer climate. This could be due to model deficiencies in ENSO dynamics and limitations in persistence model when predicting ENSO
Emplacement of Antarctic ice sheet mass affects circumpolar ocean flow
No full textDuring the Cenozoic the Antarctic continent experienced large fluctuations in ice-sheet volume. We investigate the effects of Glacial Isostatic Adjustment (GIA) on Southern Ocean circulation for the first continental scale glaciation of Antarctica (similar to 34 Myr) by combining solid Earth and ocean dynamic modeling. A newly compiled global early Oligocene topography is used to run a solid Earth model forced by a growing Antarctic ice sheet. A regional Southern Ocean zonal isopycnal adiabatic ocean model is run under ice-free and fully glaciated (GIA) conditions. We find that GIA-induced deformations of the sea bottom on the order of 50 m are large enough to affect the pressure and density variations driving the ocean flow around Antarctica. Throughout the Southern Ocean, frontal patterns are shifted several degrees, velocity changes are regionally more than 100%, and the zonal transport decreases in mean and variability. The model analysis suggests that GIA induced ocean flow variations alone could impact local nutrient variability, erosion and sedimentation rates, or ocean heat transport. These effects may be large enough to require consideration when interpreting the results of Southern Ocean sediment cores
Stable isotope evidence for rapid uplift of the central Apennines since the late Pliocene
No full textThe central Apennines, an accretionary wedge overlying an area of slab detachment, are characterized by prominent topography, active normal faulting, and high uplift rates. However, previous studies have failed to resolve the surface uplift history, complicating efforts to link the topographic evolution with underlying geodynamic processes. We aim to better quantify orographic changes by using stable oxygen isotope paleoaltimetry. Modern surface water δ18O are 5‰ lower at high elevation than at sea level, reflecting orographic rainout over the Apennines. We present 262 new lacustrine and paleosol carbonate δ18O measurements collected from ten extensional intermontane basins—spanning both high and low elevations—and combine these with 1,166 published δ18O data, permitting us to constrain changes in δ18O both spatially and temporally. Since the Pliocene, δ18O in present-day high-elevation basins has continuously decreased, even as δ18O in lowland basins has remained constant over time. We attribute this continuous 5‰ shift to increased orographic rainout as the central Apennines were uplifted. We estimate an increase in mean elevation of approximately 1–2 km since the late Pliocene, and these estimates match the suggested timing and expected amplitude of slab break-off related uplift. This supports the hypothesis that the opening of the Adriatic slab window and associated mantle flow contributed significantly to building topography in the central Apennines. © 2020 Elsevier B.V
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Effects of the Pliensbachian–Toarcian Boundary Event on carbonate productivity of a Tethyan platform and slope
No full textISSN:2572-4525ISSN:2572-4517ISSN:2572-451
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
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