bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/Virgo GW170817. VI. Radio Constraints on a Relativistic Jet and Predictions for Late-time Emission from the Kilonova Ejecta
Authors: Alexander K. D. , Berger E. , Fong W. , Williams P. K. G. , Guidorzi C. , Margutti R. , Metzger B. D. , Annis J. , Blanchard P. K. , Brout D. , Brown D. A. , Chen H.-Y. , Chornock R. , Cowperthwaite P. S. , Drout M. , Eftekhari T. , Frieman J. , Holz D. E. , Nicholl M. , Rest A. , Sako M. , Soares-Santos M. , Villar V. A. 
Published: October 2017

Abstract
We present Very Large Array (VLA) and Atacama Large Millimeter/submillimeter Array (ALMA) radio observations of GW170817, the first Laser Interferometer Gravitational-wave Observatory (LIGO)/Virgo gravitational wave (GW) event from a binary neutron star merger and the first GW event with an electromagnetic (EM) counterpart. Our data include the first observations following the discovery of the optical transient at both the centimeter (13.7 hr post-merger) and millimeter (2.41 days post-merger) bands. We detect faint emission at 6 GHz at 19.47 and 39.23 days after the merger, but not in an earlier observation at 2.46 days. We do not detect cm/mm emission at the position of the optical counterpart at frequencies of 10–97.5 GHz at times ranging from 0.6 to 30 days post-merger, ruling out an on-axis short gamma-ray burst (SGRB) for energies

≳

10

48

erg. For fiducial SGRB parameters, our limits require an observer viewer angle of ≳20°. The radio and X-ray data can be jointly explained as the afterglow emission from an SGRB with a jet energy of

∼

10

49

–

10

50

erg that exploded in a uniform density environment with

n
∼

10

−
4

–

10

−
2

cm−3, viewed at an angle of ∼20°–40° from the jet axis. Using the results of our light curve and spectral modeling, in conjunction with the inference of the circumbinary density, we predict the emergence of late-time radio emission from the deceleration of the kilonova (KN) ejecta on a timescale of ∼5–10 years that will remain detectable for decades with next-generation radio facilities, making GW170817 a compelling target for long-term radio monitoring.
The Unprecedented Properties of the First Electromagnetic Counterpart to a Gravitational-wave Source
Authors: Siebert M. R. , Foley R. J. , Drout M. R. , Kilpatrick C. D. , Shappee B. J. , Coulter D. A. , Kasen D. , Madore B. F. , Murguia-Berthier A. , Pan Y.-C. , Piro A. L. , Prochaska J. X. , Ramirez-Ruiz E. , Rest A. , Contreras C. , Morrell N. , Rojas-Bravo C. , Simon J. D. 
Published: October 2017

Abstract
We discovered Swope Supernova Survey 2017a (SSS17a) in the LIGO/Virgo Collaboration (LVC) localization volume of GW170817, the first detected binary neutron star (BNS) merger, only 10.9 hr after the trigger. No object was present at the location of SSS17a only a few days earlier, providing a qualitative spatial and temporal association with GW170817. Here, we quantify this association, finding that SSS17a is almost certainly the counterpart of GW170817, with the chance of a coincidence being ≤

(90% confidence). We arrive at this conclusion by comparing the optical properties of SSS17a to other known astrophysical transients, finding that SSS17a fades and cools faster than any other observed transient. For instance, SSS17a fades >5 mag in g within 7 days of our first data point, while all other known transients of similar luminosity fade by <1 mag during the same time period. Its spectra are also unique, being mostly featureless, even as it cools. The rarity of “SSS17a-like” transients combined with the relatively small LVC localization volume and recent non-detection imply the extremely unlikely chance coincidence. We find that the volumetric rate of SSS17a-like transients is ≤

Gpc−3 yr−1 and the Milky Way rate is

per century. A transient survey designed to discover similar events should be high cadence and observe in red filters. The LVC will likely detect substantially more BNS mergers than current optical surveys will independently discover SSS17a-like transients, however a 1 day cadence survey with the Large Synoptic Survey Telescope (LSST) could discover an order of magnitude more events.
Reconciling differences in stratospheric ozone composites
Authors: Ball William T. , Alsing Justin , Mortlock Daniel J. , Rozanov Eugene V. , Tummon Fiona , Haigh Joanna D. 
Published: October 2017

Abstract. Observations of stratospheric ozone from multiple instruments now span three decades; combining these into composite datasets allows long-term ozone trends to be estimated. Recently, several ozone composites have been published, but trends disagree by latitude and altitude, even between composites built upon the same instrument data. We confirm that the main causes of differences in decadal trend estimates lie in (i) steps in the composite time series when the instrument source data changes and (ii) artificial sub-decadal trends in the underlying instrument data. These artefacts introduce features that can alias with regressors in multiple linear regression (MLR) analysis; both can lead to inaccurate trend estimates. Here, we aim to remove these artefacts using Bayesian methods to infer the underlying ozone time series from a set of composites by building a joint-likelihood function using a Gaussian-mixture density to model outliers introduced by data artefacts, together with a data-driven prior on ozone variability that incorporates knowledge of problems during instrument operation. We apply this Bayesian self-calibration approach to stratospheric ozone in 10° bands from 60° S to 60° N and from 46 to 1 hPa (∼ 21–48 km) for 1985–2012. There are two main outcomes: (i) we independently identify and confirm many of the data problems previously identified, but which remain unaccounted for in existing composites; (ii) we construct an ozone composite, with uncertainties, that is free from most of these problems – we call this the BAyeSian Integrated and Consolidated (BASIC) composite. To analyse the new BASIC composite, we use dynamical linear modelling (DLM), which provides a more robust estimate of long-term changes through Bayesian inference than MLR. BASIC and DLM, together, provide a step forward in improving estimates of decadal trends. Our results indicate a significant recovery of ozone since 1998 in the upper stratosphere, of both northern and southern midlatitudes, in all four composites analysed, and particularly in the BASIC composite. The BASIC results also show no hemispheric difference in the recovery at midlatitudes, in contrast to an apparent feature that is present, but not consistent, in the four composites. Our overall conclusion is that it is possible to effectively combine different ozone composites and account for artefacts and drifts, and that this leads to a clear and significant result that upper stratospheric ozone levels have increased since 1998, following an earlier decline.
Southern Hemisphere bog persists as a strong carbon sink during droughts
Authors: Goodrich Jordan P. , Campbell David I. , Schipper Louis A. 
Published: October 2017

Abstract. Peatland ecosystems have been important global carbon sinks throughout the Holocene. Most of the research on peatland carbon budgets and effects of variable weather conditions has been done in Northern Hemisphere Sphagnum-dominated systems. Given their importance in other geographic and climatic regions, a better understanding of peatland carbon dynamics is needed across the spectrum of global peatland types. In New Zealand, much of the historic peatland area has been drained for agriculture but little is known about rates of carbon exchange and storage in unaltered peatland remnants that are dominated by the jointed wire rush, Empodisma robustum. We used eddy covariance to measure ecosystem-scale CO2 and CH4 fluxes and a water balance approach to estimate the sub-surface flux of dissolved organic carbon from the largest remaining raised peat bog in New Zealand, Kopuatai bog. The net ecosystem carbon balance (NECB) was estimated over four years, which included two drought summers, a relatively wet summer, and a meteorologically average summer. In all measurement years, the bog was a substantial sink for carbon, ranging from 134.7 to 216.9 gC m−2 yr−1, owing to the large annual net ecosystem production (161.8 to 244.9 gCO2–C m−2 yr−1). Annual methane fluxes were large relative to most Northern Hemisphere peatlands (14.2 to 21.9 gCH4–C m−2 yr−1), although summer and autumn emissions were highly sensitive to dry conditions, leading to very predictable seasonality according to water table position. The annual flux of dissolved organic carbon was similar in magnitude to methane emissions but less variable, ranging from 11.7 to 12.8 gC m−2 yr−1. Dry conditions experienced during late summer droughts led to significant reductions in annual carbon storage, which resulted nearly equally from enhanced ecosystem respiration due to lowered water tables and increased temperatures, and from reduced gross primary production due to vapor pressure deficit-related stresses to the vegetation. However, the net C uptake of Kopuatai bog during drought years was large relative to even the maximum reported NECB from Northern Hemisphere bogs. Furthermore, global warming potential fluxes indicated the bog was a strong sink for greenhouse gases in all years despite the relatively large annual methane emissions. Our results suggest that adaptations of E. robustum to dry conditions lead to a resilient peatland drought response of the NECB.
A globally calibrated scheme for generating daily meteorology from monthly statistics: Global-WGEN (GWGEN) v1.0
Authors: Sommer Philipp S. , Kaplan Jed O. 
Published: October 2017

Abstract. While a wide range of Earth system processes occur at daily and even subdaily timescales, many global vegetation and other terrestrial dynamics models historically used monthly meteorological forcing both to reduce computational demand and because global datasets were lacking. Recently, dynamic land surface modeling has moved towards resolving daily and subdaily processes, and global datasets containing daily and subdaily meteorology have become available. These meteorological datasets, however, cover only the instrumental era of the last approximately 120 years at best, are subject to considerable uncertainty, and represent extremely large data files with associated computational costs of data input/output and file transfer. For periods before the recent past or in the future, global meteorological forcing can be provided by climate model output, but the quality of these data at high temporal resolution is low, particularly for daily precipitation frequency and amount. Here, we present GWGEN, a globally applicable statistical weather generator for the temporal downscaling of monthly climatology to daily meteorology. Our weather generator is parameterized using a global meteorological database and simulates daily values of five common variables: minimum and maximum temperature, precipitation, cloud cover, and wind speed. GWGEN is lightweight, modular, and requires a minimal set of monthly mean variables as input. The weather generator may be used in a range of applications, for example, in global vegetation, crop, soil erosion, or hydrological models. While GWGEN does not currently perform spatially autocorrelated multi-point downscaling of daily weather, this additional functionality could be implemented in future versions.
Uma Análise sobre a Institucionalização da Região Metropolitana de Feira de Santana (BA) / An Analysis on the Institutionalization of the Metropolitan Region of Feira de Santana (BA)
Authors: Lopes Keilla Petronilia Santos 
Published: October 2017

<p>Este estudo objetiva pesquisar sobre o processo que instituiu a Região Metropolitana de Feira de Santana (RMFS) sob a ótica da Geografia. Para tanto ocorre o uso de referencial teórico-conceitual e observações. Diante da pesquisa é possível concluir que a decisão da criação da RMFS é muito mais uma questão política do que uma construção social.</p><p><strong> </strong></p><p><strong>Palavras-chave: </strong>planejamento urbano; regiões metropolitanas; Região Metropolitana de Feira de Santana.</p><p> </p><p><strong>Abstract</strong></p><p>This study aims to research about the process that instituted the Metropolitan Region of Feira de Santana (RMFS) from the perspective of Geography. For this, the use of theoretical-conceptual reference and observations is made. In view of the research, it is possible to conclude that the decision to create RMFS is much more a political question than a social construction.</p><p><strong> </strong></p><p><strong>Keywords: </strong>urbanplanning; metropolitan regions; metropolitan Region of Feira de Santana.</p>
Réflexivité, pouvoirs et transformation des pratiques1
Authors: Dierckx Carine 
Published: October 2017

Dans le domaine de l’intervention sociale, on assiste aujourd’hui à des appels multiples à la réflexivité des acteurs comme des institutions, dans le cadre de politiques publiques devenues « activantes », et dans le contexte plus global d’une société dite « réflexive ». L’objectif de cet article est de montrer comment l’outillage conceptuel de Foucault permet de problématiser ces divers usages de la réflexivité et leurs relations au pouvoir dans les pratiques, et d’en dégager certains enjeux et potentialités éthiques dans la transformation des pratiques d’intervention sociale.
Efectos de la comunicación dialógica y la conciencia fonológica en el aprendizaje inicial de la escritura de palabras en español
Authors:   Universidad de Alicante (España), Gutiérrez-Fresneda Raúl 
Published: October 2017

El aprendizaje de la escritura constituye uno de los referentes de la investigación educativa por la relevancia que presenta en el proceso de alfabetización. En sistemas alfabéticos como el español, en los que la escritura representa la estructura fonológica del habla, el éxito en el aprendizaje de la lengua escrita implica que el niño sea capaz de reconocer los componentes sonoros de su lengua. Este es un requisito necesario, pero no suficiente, ya que además se ha de establecer una adecuada relación entre los fonemas y los grafemas que los representan, puesto que el éxito en el aprendizaje de la escritura implica esta destreza. El propósito de este trabajo fue analizar si con la utilización de programas que integren dinámicas de comunicación dialógica junto con el desarrollo de las habilidades de conciencia fonológica se favorece el aprendizaje de la escritura en las primeras edades. Se empleó un diseño cuasi-experimental de comparación entre grupos con medidas pretest y postest. Participaron 448 alumnos con edades comprendidas entre los 5 y los 6 años. Los resultados ponderan el valor potencial de la instrucción y apoyan el desarrollo de modelos de enseñanza que integren la conciencia fonológica junto con prácticas de comunicación dialógica en la dinámica del aula.
Reconstructing the Evolution of the Submarine Monterey Canyon System From Os, Nd, and Pb Isotopes in Hydrogenetic Fe‐Mn Crusts
Authors: Conrad T. A. , Nielsen S. G. , Peucker‐Ehrenbrink B. , Blusztajn J. , Winslow D. , Hein J. R. , Paytan A. 
Published: October 2017

AbstractThe sources of terrestrial material delivered to the California margin over the past 7 Myr were assessed using 187Os/188Os, Nd, and Pb isotopes in hydrogenetic ferromanganese crusts from three seamounts along the central and southern California margin. From 6.8 to 4.5 (±0.5) Ma, all three isotope systems show more radiogenic values at Davidson Seamount, located near the base of the Monterey Canyon System, than in Fe‐Mn crusts from the more remote Taney and Hoss Seamounts. At the Taney Seamounts, approximately 225 km farther offshore from Davidson Seamount, 187Os/188Os values, but not Pb and Nd isotope ratios, also deviate from the Cenozoic seawater curve toward more radiogenic values from 6.8 to 4.5 (±0.5) Ma. However, none of the isotope systems in Fe‐Mn crusts deviate from seawater at Hoss Seamount located approximately 450 km to the south. The regional gradients in isotope ratios indicate that substantial input of dissolved and particulate terrestrial material into the Monterey Canyon System is responsible for the local deviations in the seawater Nd, Pb, and Os isotope compositions from 6.8 to 4.5 (±0.5) Ma. The isotope ratios recorded in Fe‐Mn crusts are consistent with a southern Sierra Nevada or western Basin and Range provenance of the terrestrial material which was delivered by rivers to the canyon. The exhumation of the modern Monterey Canyon must have begun between 10 and 6.8 ± 0.5 Ma, as indicated by our data, the age of incised strata, and paleo‐location of the Monterey Canyon relative to the paleo‐coastline.
Seismic Observations Indicating That the 2015 Ogasawara (Bonin) Earthquake Ruptured Beneath the 660 km Discontinuity
Authors: Kuge Keiko 
Published: October 2017

AbstractThe termination of deep earthquakes at a depth of ~700 km is a key feature for understanding the physical mechanism of deep earthquakes. The ~680 km deep 30 May 2015, Ogasawara (Bonin) earthquake (Mw 7.9) and its aftershocks were recorded by seismic stations at distances from 7° to 19°. Synthetic seismograms indicate that the P waveforms depend on whether the earthquake is located above or below the 660 km discontinuity. In this study, I show that broadband recordings indicate that the 2015 earthquake may have occurred below the 660 km velocity discontinuity. Recordings of the P wave from the strongest aftershock lack evidence for wave triplication expected when a subhorizontal discontinuity underlies the hypocenter. Theoretical waveforms computed with a 660 km discontinuity above the aftershock and mainshock match the observed waveforms more accurately. These observations may indicate earthquake ruptures due to mantle minerals other than olivine or strong deformation of the 660 km phase transition.
Attribution of Observed Streamflow Changes in Key British Columbia Drainage Basins
Authors: Najafi Mohammad Reza , Zwiers Francis W. , Gillett Nathan P. 
Published: October 2017

AbstractWe study the observed decline in summer streamflow in four key river basins in British Columbia (BC), Canada, using a formal detection and attribution (D&A) analysis procedure. Reconstructed and simulated streamflow is generated using the semidistributed variable infiltration capacity hydrologic model, which is driven by 1/16° gridded observations and downscaled climate model data from the Coupled Model Intercomparison Project phase 5 (CMIP5), respectively. The internal variability of the regional hydrologic components using ~5100 years of streamflow was simulated using CMIP5 preindustrial control runs. Results show that the observed changes in summer streamflow are inconsistent with simulations representing the responses to natural forcing factors alone, while the response to anthropogenic and natural forcing factors combined is detected in these changes. A two‐signal D&A analysis indicates that the effects of anthropogenic (ANT) forcing factors are discernable from natural forcing in BC, albeit with large uncertainties.
Weak Thermocline Mixing in the North Pacific Low‐Latitude Western Boundary Current System
Authors: Liu Zhiyu , Lian Qiang , Zhang Fangtao , Wang Lei , Li Mingming , Bai Xiaolin , Wang Jianing , Wang Fan 
Published: October 2017

AbstractDespite its potential importance in the global climate system, mixing properties of the North Pacific low‐latitude western boundary current system (LLWBC) remained unsampled until very recently. We report here on the first measurements of turbulence microstructure associated with these currents, made in the western boundary region of the tropical North Pacific east of the Philippines. The results suggest that thermocline mixing in the North Pacific LLWBC is generally weak with the diapycnal diffusivity κρ∼O(10−6) m2 s−1. This is consistent with predictions from internal wave‐wave interaction theory that mixing due to internal wave breaking is significantly reduced at low latitudes. Enhanced mixing is found to be associated with a permanent cyclonic eddy, the Mindanao Eddy, but mainly at its south and north flanks. There, κρ is elevated by an order of magnitude due to eddy‐induced geostrophic shear. Mixing in the eddy core is at the background level with no indication of enhancement.
Joint Modulation of Intraseasonal Rainfall in Tropical Australia by the Madden‐Julian Oscillation and El Niño‐Southern Oscillation
Authors: Ghelani Roohi P. S. , Oliver Eric C. J. , Holbrook Neil J. , Wheeler Matthew C. , Klotzbach Philip J. 
Published: October 2017

AbstractRainfall in tropical Australia is a critical resource for the agricultural sector. However, its high variability implores improvements in our understanding of its variability. Australian tropical rainfall is influenced by both the Madden‐Julian Oscillation (MJO) on intraseasonal time scales and El Niño‐Southern Oscillation (ENSO) on interannual time scales. This study examines the joint relationship between the MJO, ENSO, and tropical Australian rainfall variability. We analyze daily precipitation data from stations across tropical Australia during the wet season (November to April). The wet season rainfall response to the MJO is found to be greater during El Niño than La Niña. We demonstrate that this relationship is not due to the statistical relationship between the MJO and ENSO indices but instead due to differences in how the MJO modulates the large‐scale circulation during El Niño versus during La Niña.
Tropical Forcing of the Summer East Atlantic Pattern
Authors: Wulff C. Ole , Greatbatch Richard J. , Domeisen Daniela I. V. , Gollan Gereon , Hansen Felicitas 
Published: October 2017

AbstractThe Summer East Atlantic (SEA) mode is the second dominant mode of summer low‐frequency variability in the Euro‐Atlantic region. Using reanalysis data, we show that SEA‐related circulation anomalies significantly influence temperatures and precipitation over Europe. We present evidence that part of the interannual SEA variability is forced by diabatic heating anomalies of opposing signs in the tropical Pacific and Caribbean that induce an extratropical Rossby wave train. This precipitation dipole is related to SST anomalies characteristic of the developing El Niño–Southern Oscillation phases. Seasonal hindcast experiments forced with observed sea surface temperatures (SSTs) exhibit skill at capturing the interannual SEA variability corroborating the proposed mechanism and highlighting the possibility for improved prediction of boreal summer variability. Our results indicate that tropical forcing of the SEA likely played a role in the dynamics of the 2015 European heat wave.