bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fault Zone Permeability Decrease Following Large Earthquakes in a Hydrothermal System
Authors: Shi Zheming , Zhang Shouchuan , Yan Rui , Wang Guangcai 
Published: January 2018

AbstractSeismic wave shaking‐induced permeability enhancement in the shallow crust has been widely observed. Permeability decrease, however, is seldom reported. In this study, we document coseismic discharge and temperature decrease in a hot spring following the 1996 Lijiang Mw 7.0 and the 2004 Mw 9.0 earthquakes in the Balazhang geothermal field. We use three different models to constrain the permeability change and the mechanism of coseismic discharge decrease, and we use an end‐member mixing model for the coseismic temperature change. Our results show that the earthquake‐induced permeability decrease in the fault zone reduced the recharge from deep hot water, which may be the mechanism that explains the coseismic discharge and temperature responses. The changes in the hot spring response reflect the dynamic changes in the hydrothermal system; in the future, the earthquake‐induced permeability decrease should be considered when discussing controls on permeability.
Internal Variability and Disequilibrium Confound Estimates of Climate Sensitivity From Observations
Authors: Marvel Kate , Pincus Robert , Schmidt Gavin A. , Miller Ron L. 
Published: January 2018

AbstractAn emerging literature suggests that estimates of equilibrium climate sensitivity (ECS) derived from recent observations and energy balance models are biased low because models project more positive climate feedback in the far future. Here we use simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to show that across models, ECS inferred from the recent historical period (1979–2005) is indeed almost uniformly lower than that inferred from simulations subject to abrupt increases in CO2 radiative forcing. However, ECS inferred from simulations in which sea surface temperatures are prescribed according to observations is lower still. ECS inferred from simulations with prescribed sea surface temperatures is strongly linked to changes to tropical marine low clouds. However, feedbacks from these clouds are a weak constraint on long‐term model ECS. One interpretation is that observations of recent climate changes constitute a poor direct proxy for long‐term sensitivity.
Investigation of the Electron Density Variation During the 21 August 2017 Solar Eclipse
Authors: Reinisch B. W. , Dandenault P. B. , Galkin I. A. , Hamel R. , Richards P. G. 
Published: January 2018

AbstractThis paper presents a comparison of modeled and measured electron densities for the 21 August 2017 solar eclipse across the USA. The location of the instrument was (43.81°N, 247.32°E) where the maximum obscuration of 99.6% occurred at 17.53 hr UT on 21 August. The solar apparent time was 9.96 hr, and the duration of the eclipse was 2.7 hr. It was found that if it is assumed that there are no chromosphere emissions at totality, ~30% coronal emission remaining at totality gave the best fit to the electron density variation at 150 km. The 30% coronal emission estimate has uncertainties associated with respect to uncertainties in the solar spectrum, the measured electron density, and the amount of chromosphere emissions remaining at totality. The agreement between the modeled and measured electron densities is excellent at 150 km with the assumed 30% coronal emission at totality. At other altitudes, the agreement is very good, but the altitude profile would be improved if the model peak electron density (NmF2) decayed more slowly to better match the data. The minimum NmF2 in the model occurs ~10 min after totality when it decreases to 0.55 from its noneclipse value. The minimum of the NmF2 data occurs between 6 and 10 min after totality but is ~15% larger. The total electron content decreases to 0.65 of its preeclipse value. These relative changes agree well with those predicted by others prior to the eclipse.
A New Estimate of North American Mountain Snow Accumulation From Regional Climate Model Simulations
Authors: Wrzesien Melissa L. , Durand Michael T. , Pavelsky Tamlin M. , Kapnick Sarah B. , Zhang Yu , Guo Junyi , Shum C. K. 
Published: January 2018

AbstractDespite the importance of mountain snowpack to understanding the water and energy cycles in North America's montane regions, no reliable mountain snow climatology exists for the entire continent. We present a new estimate of mountain snow water equivalent (SWE) for North America from regional climate model simulations. Climatological peak SWE in North America mountains is 1,006 km3, 2.94 times larger than previous estimates from reanalyses. By combining this mountain SWE value with the best available global product in nonmountain areas, we estimate peak North America SWE of 1,684 km3, 55% greater than previous estimates. In our simulations, the date of maximum SWE varies widely by mountain range, from early March to mid‐April. Though mountains comprise 24% of the continent's land area, we estimate that they contain ~60% of North American SWE. This new estimate is a suitable benchmark for continental‐ and global‐scale water and energy budget studies.
Sensitivity of Homogeneous Ice Nucleation to Aerosol Perturbations and Its Implications for Aerosol Indirect Effects Through Cirrus Clouds
Authors: Liu X. , Shi X. 
Published: January 2018

AbstractThe magnitude and sign of anthropogenic aerosol impacts on cirrus clouds through ice nucleation are still very uncertain. In this study, aerosol sensitivity (ηα), defined as the sensitivity of the number concentration (Ni) of ice crystals formed from homogeneous ice nucleation to aerosol number concentration (Na), is examined based on simulations from a cloud parcel model. The model represents the fundamental process of ice crystal formation that results from homogeneous nucleation. We find that the geometric dispersion (σ) of the aerosol size distribution used in the model is a key factor for ηα. For a monodisperse size distribution, ηα is close to zero in vertical updrafts (V < 50 cm s−1) typical of cirrus clouds. However, ηα increases to 0.1–0.3 (i.e., Ni increases by a factor of 1.3–2.0 for a tenfold increase in Na) if aerosol particles follow lognormal size distributions with a σ of 1.6–2.3 in the upper troposphere. By varying the input aerosol and environmental parameters, our model reproduces a large range of ηα values derived from homogeneous ice nucleation parameterizations widely used in global climate models (GCMs). The differences in ηα from these parameterizations can translate into a range of anthropogenic aerosol longwave indirect forcings through cirrus clouds from 0.05 to 0.36 W m−2 with a GCM. Our study suggests that a larger ηα (0.1–0.3) is more plausible and the homogeneous nucleation parameterizations should include a realistic aerosol size distribution to accurately quantify anthropogenic aerosol indirect effects.
Localized Oscillatory Energy Conversion in Magnetopause Reconnection
Authors: Burch J. L. , Ergun R. E. , Cassak P. A. , Webster J. M. , Torbert R. B. , Giles B. L. , Dorelli J. C. , Rager A. C. , Hwang K.‐J. , Phan T. D. , Genestreti K. J. , Allen R. C. , Chen L.‐J. , Wang S. , Gershman D. , Le Contel O. , Russell C. T. , Strangeway R. J. , Wilder F. D. , Graham D. B. , Hesse M. , Drake J. F. , Swisdak M. , Price L. M. , Shay M. A. , Lindqvist P.‐A. , Pollock C. J. , Denton R. E. , Newman D. L. 
Published: January 2018

AbstractData from the NASA Magnetospheric Multiscale mission are used to investigate asymmetric magnetic reconnection at the dayside boundary between the Earth's magnetosphere and the solar wind. High‐resolution measurements of plasmas and fields are used to identify highly localized (~15 electron Debye lengths) standing wave structures with large electric field amplitudes (up to 100 mV/m). These wave structures are associated with spatially oscillatory energy conversion, which appears as alternatingly positive and negative values of J · E. For small guide magnetic fields the wave structures occur in the electron stagnation region at the magnetosphere edge of the electron diffusion region. For larger guide fields the structures also occur near the reconnection X‐line. This difference is explained in terms of channels for the out‐of‐plane current (agyrotropic electrons at the stagnation point and guide field‐aligned electrons at the X‐line).
Pitch Angle Scattering of Upgoing Electron Beams in Jupiter's Polar Regions by Whistler Mode Waves
Authors: Elliott S. S. , Gurnett D. A. , Kurth W. S. , Clark G. , Mauk B. H. , Bolton S. J. , Connerney J. E. P. , Levin S. M. 
Published: January 2018

AbstractThe Juno spacecraft's Jupiter Energetic‐particle Detector Instrument has observed field‐aligned, unidirectional (upgoing) electron beams throughout most of Jupiter's entire polar cap region. The Waves instrument detected intense broadband whistler mode emissions occurring in the same region. In this paper, we investigate the pitch angle scattering of the upgoing electron beams due to interactions with the whistler mode waves. Profiles of intensity versus pitch angle for electron beams ranging from 2.53 to 7.22 Jovian radii show inconsistencies with the expected adiabatic invariant motion of the electrons. It is believed that the observed whistler mode waves perturb the electron motion and scatter them away from the magnetic field line. The diffusion equation has been solved by using diffusion coefficients which depend on the magnetic intensity of the whistler mode waves.
Fault Geometry and Slip Distribution at Depth of the 1997 Mw 7.2 Zirkuh Earthquake: Contribution of Near‐Field Displacement Data
Authors: Marchandon Mathilde , Vergnolle Mathilde , Sudhaus Henriette , Cavalié Olivier 
Published: January 2018

AbstractIn this study, we reestimate the source model of the 1997 Mw 7.2 Zirkuh earthquake (northeastern Iran) by jointly optimizing intermediate‐field Interferometry Synthetic Aperture Radar data and near‐field optical correlation data using a two‐step fault modeling procedure. First, we estimate the geometry of the multisegmented Abiz fault using a genetic algorithm. Then, we discretize the fault segments into subfaults and invert the data to image the slip distribution on the fault. Our joint‐data model, although similar to the Interferometry Synthetic Aperture Radar‐based model to the first order, highlights differences in the fault dip and slip distribution. Our preferred model is ∼80° west dipping in the northern part of the fault, ∼75° east dipping in the southern part and shows three disconnected high slip zones separated by low slip zones. The low slip zones are located where the Abiz fault shows geometric complexities and where the aftershocks are located. We interpret this rough slip distribution as three asperities separated by geometrical barriers that impede the rupture propagation. Finally, no shallow slip deficit is found for the overall rupture except on the central segment where it could be due to off‐fault deformation in quaternary deposits.
Dependence of the Onset of the Runaway Greenhouse Effect on the Latitudinal Surface Water Distribution of Earth‐Like Planets
Authors: Kodama T. , Nitta A. , Genda H. , Takao Y. , O'ishi R. , Abe‐Ouchi A. , Abe Y. 
Published: January 2018

AbstractLiquid water is one of the most important materials affecting the climate and habitability of a terrestrial planet. Liquid water vaporizes entirely when planets receive insolation above a certain critical value, which is called the runaway greenhouse threshold. This threshold forms the inner most limit of the habitable zone. Here we investigate the effects of the distribution of surface water on the runaway greenhouse threshold for Earth‐sized planets using a three‐dimensional dynamic atmosphere model. We considered a 1 bar atmosphere whose composition is similar to the current Earth's atmosphere with a zonally uniform distribution of surface water. As previous studies have already showed, we also recognized two climate regimes: the land planet regime, which has dry low‐latitude and wet high‐latitude regions, and the aqua planet regime, which is globally wet. We showed that each regime is controlled by the width of the Hadley circulation, the amount of surface water, and the planetary topography. We found that the runaway greenhouse threshold varies continuously with the surface water distribution from about 130% (an aqua planet) to 180% (the extreme case of a land planet) of the present insolation at Earth's orbit. Our results indicate that the inner edge of the habitable zone is not a single sharp boundary, but a border whose location varies depending on planetary surface condition, such as the amount of surface water. Since land planets have wider habitable zones and less cloud cover, land planets would be good targets for future observations investigating planetary habitability.
Trends and Variability in Temperature Sensitivity of Lilac Flowering Phenology
Authors: Wang Huanjiong , Dai Junhu , Rutishauser This , Gonsamo Alemu , Wu Chaoyang , Ge Quansheng 
Published: January 2018

AbstractThe responses of plant phenology to temperature variability have many consequences for ecological processes, agriculture, forestry, and human health. Temperature sensitivity (ST) of phenology could measure how and to what degree plant could phenologically track climate change. The long‐term trends and spatial patterns in ST have been well studied for vegetative phenology such as leaf unfolding, but trends to be expected for reproductive phenology in the future remain unknown. Here we investigate trends and factors driving the temporal variation of ST of first bloom date (FBD). Using the long‐term FBD records during 1963–2013 for common lilac (Syringa vulgaris) from 613 stations in Europe, we compared changes in ST from the beginning to the end of the study period. The Spearman partial correlations were used to assess the importance of four influencing factors. The results showed that the temporal changes in ST of FBD varied considerably among time scales. Mean ST decreased significantly by 0.92 days °C−1 from 1963–1972 to 2004–2013 (P < 0.01), but remained stable from 1963–1987 to 1989–2013. The strength of FBD and temperature relationship, the spring temperature variance, and winter chill all impact ST in an expected way at most stations. No consistent responses of ST on photoperiod were found. Our results imply that the trends and variability in ST of flowering phenology are driving by multiple factors and impacted by time scales. Continued efforts are still needed to further examine the flowering‐temperature relationship for other plant species in other climates and environments using similar methods to our study.
Subduction Evolution of the Dinarides and the Cretaceous Orogeny in the Eastern Alps: Hints From a New Paleotectonic Interpretation
Authors: Argnani A. 
Published: January 2018

AbstractThe geological evolution of the Dinarides and Eastern Alps is reconsidered taking into account the constraints from a new paleotectonic interpretation for the central Mediterranean. The geological record of the Dinarides suggests that more than one ocean existed between Africa and Europe in Late Triassic‐Late Jurassic. Besides the large Vardar ocean, it is inferred that the basin located to the west of the Pelagonian domain is floored by oceanic‐like lithosphere. Following the Late Jurassic‐Early Cretaceous westward obduction of the Vardar ophiolite onto Pelagonia, subduction resumed close to the European margin and continued until early Paleogene, when the Vardar oceanic basin was consumed. Subsequently, the substrate of the narrow Pindos ocean‐like basin was subducted to the east, accommodating a few hundreds of kilometers of Adria‐Eurasia convergence. Plate kinematics indicate that N‐S convergence between Africa and Europe initiated only after the Cenomanian, well after ophiolite obduction occurred in the Dinarides‐Hellenides. In the Eastern Alps, however, an early Late Cretaceous orogeny has been recorded, separated from the tectonic evolution of the Alps sensu strictu. This Cretaceous orogeny of the Eastern Alps has not been fully understood. The new reconstructions suggest that the Pindos and Vardar oceans merged north of Pelagonia and were confined by a transform fault bounding to the south the Austroalpine domain. Within this frame, where the occurrence of wider oceanic domains is considered, the Cretaceous orogeny of the Eastern Alps can be linked to different episodes of ophiolite obduction and a subsequent shift of tectonic activity that has been recorded in the Dinarides.
Brain atrophy and disability worsening in primary progressive multiple sclerosis: insights from the INFORMS study
Authors: Miller David H. , Lublin Fred D. , Sormani Maria Pia , Kappos Ludwig , Yaldizli Özgür , Freedman Mark S. , Cree Bruce A. C. , Weiner Howard L. , Lubetzki Catherine , Hartung Hans‐Peter , Montalban Xavier , Uitdehaag Bernard M. J. , MacManus David G. , Yousry Tarek A. , Gandini Wheeler‐Kingshott Claudia A. M. , Li Bingbing , Putzki Norman , Merschhemke Martin , Häring Dieter A. , Wolinsky Jerry S. 
Published: January 2018

AbstractObjectiveTo investigate the relationship between brain volume and disability worsening over ≥3 years in the natural history of primary progressive multiple sclerosis using data from the placebo group of the INFORMS trial (n = 487; clinicaltrials.gov NCT00731692).MethodsMagnetic resonance imaging scans were collected annually. Brain volume loss was determined using SIENA. Patients were stratified by baseline normalized brain volume after adjusting for demographic and disease‐burden covariates.ResultsBaseline normalized brain volume was predictive of disability worsening: Risk of 3‐month confirmed disability progression was reduced by 36% for high versus low baseline normalized brain volume (Cox's model hazard ratio 0.64, P = 0.0339; log‐rank test: P = 0.0297). Moreover, on‐study brain volume loss was significantly associated with disability worsening (P = 0.012) and was evident in patients with or without new lesions or relapses. Brain volume loss depended significantly on baseline T2 lesion volume (P < 0.0001). Despite low inflammatory activity at baseline (13% of patients had gadolinium‐enhancing lesions) and throughout the study (mean 0.5 new/enlarging T2 lesions and 172 mm3 T2 lesion volume increase per year), baseline T2 lesion volume was substantial (mean 10 cm3). Lower normalized brain volume at baseline correlated with higher baseline T2 volume and older age (both P < 0.0001).InterpretationBaseline brain volume and the rate of ongoing brain atrophy are significantly associated with disability worsening in primary progressive multiple sclerosis. Brain volume loss is significantly related to baseline T2 lesion volume, but partially independent of new lesion activity, which might explain the limited efficacy of anti‐inflammatory treatment.
Effects of background chewing sounds on learning: The role of misophonia sensitivity
Authors: Seaborne Amanda , Fiorella Logan 
Published: January 2018

SummaryMisophonia refers to one's sensitivity to specific sounds, which can range from minor annoyance to extreme distress. This experiment tested the role of individual differences in misophonia sensitivity on learning. College students read a text passage about migraines in a quiet room with 2 or 3 other participants and 1 confederate. In some sessions, the confederate audibly chewed gum while reading the text (sound group); in other sessions, the confederate read silently (control group). All participants then completed a comprehension test on the material, followed by an assessment of their misophonia sensitivity. Although there was no overall difference between the two groups on the comprehension test, misophonia sensitivity significantly moderated the effect of the trigger sound on learning. Students who scored relatively high on misophonia sensitivity performed worse on the comprehension test if they were in the sound group but performed better if they were in the control group.
Supporting Arthritis and Employment Across the Life Course: A Qualitative Study
Authors: Jetha Arif , Gignac Monique A. M. , Bowring Julie , Tucker Sean , Connelly Catherine E. , Proulx Laurie , Martin Ginis Kathleen A. 
Published: January 2018

ObjectiveTo examine the need for and availability and use of formal and informal workplace resources and to uncover differences across the life course in adults with arthritis.MethodsFocus groups and interviews were conducted with young (aged 18–34 years; n = 7), middle‐aged (35–54 years; n = 13), and older adults (≥55 years; n = 25) with a diagnosis of inflammatory arthritis, osteoarthritis, or other rheumatic disease. Participants were asked about their employment experiences, formal and informal workplace resource needs, and availability and use of workplace resources. Differences based on chronological, functional, psychosocial, organizational, and lifespan dimensions of age were examined. A modified grounded theory approach was used to inductively analyze the data.ResultsYoung, middle‐aged, and older adult participants required similar workplace resources. Across all participants, scheduling modifications tended to be the most needed workplace resource. In contrast, the perceived availability and use of formal workplace resources differed among participants. Young adult participants and those who were newer to their jobs reported that workplace resources were less available and utilized. Middle‐aged and older adults reported greater availability of workplace resources. Scheduling accommodations and at‐work modifications were the workplace resources that were used most by middle‐aged and older adults, respectively.ConclusionSimilar workplace resources could meet the employment needs of individuals with arthritis across the life course. Attention should be paid to young adults and those who are new to their jobs, because they may perceive more barriers to accessing formal workplace resources and be susceptible to work disability.
Infrared Organic Light‐Emitting Diodes with Carbon Nanotube Emitters
Authors: Graf Arko , Murawski Caroline , Zakharko Yuriy , Zaumseil Jana , Gather Malte C. 
Published: January 2018

AbstractWhile organic light‐emitting diodes (OLEDs) covering all colors of the visible spectrum are widespread, suitable organic emitter materials in the near‐infrared (nIR) beyond 800 nm are still lacking. Here, the first OLED based on single‐walled carbon nanotubes (SWCNTs) as the emitter is demonstrated. By using a multilayer stacked architecture with matching charge blocking and charge‐transport layers, narrow‐band electroluminescence at wavelengths between 1000 and 1200 nm is achieved, with spectral features characteristic of excitonic and trionic emission of the employed (6,5) SWCNTs. Here, the OLED performance is investigated in detail and it is found that local conduction hot‐spots lead to pronounced trion emission. Analysis of the emissive dipole orientation shows a strong horizontal alignment of the SWCNTs with an average inclination angle of 12.9° with respect to the plane, leading to an exceptionally high outcoupling efficiency of 49%. The SWCNT‐based OLEDs represent a highly attractive platform for emission across the entire nIR.