bluuebunny/crossref_metadata_2025_split huggingface dataset:
Groundwater Buffers Decreasing Glacier Melt in an Andean Watershed—But Not Forever
Authors: Somers Lauren D. , McKenzie Jeffrey M. , Mark Bryan G. , Lagos Pablo , Ng Gene‐Hua Crystal , Wickert Andrew D. , Yarleque Christian , Baraër Michel , Silva Yamina 
Published: November 2019

AbstractAccelerating mountain glacier recession in a warming climate threatens the sustainability of mountain water resources. The extent to which groundwater will provide resilience to these water resources is unknown, in part due to a lack of data and poorly understood interactions between groundwater and surface water. Here we address this knowledge gap by linking climate, glaciers, surface water, and groundwater into an integrated model of the Shullcas Watershed, Peru, in the tropical Andes, the region experiencing the most rapid mountain‐glacier retreat on Earth. For a range of climate scenarios, our model projects that glaciers will disappear by 2100. The loss of glacial meltwater will be buffered by relatively consistent groundwater discharge, which only receives minor recharge (~2%) from glacier melt. However, increasing temperature and associated evapotranspiration, alongside potential decreases in precipitation, will decrease groundwater recharge and streamflow, particularly for the RCP 8.5 emission scenario.
Impact Degassing of H2 on Early Mars and its Effect on the Climate System
Authors: Haberle Robert M. , Zahnle Kevin , Barlow Nadine G. , Steakley Kathryn E. 
Published: November 2019

AbstractImpacts on early Mars can produce H2 and CH4 in the thermal plume. In a thick CO2 atmosphere, collision‐induced absorptions between CO2‐H2 and CO2‐CH4 can boost the greenhouse effect. We construct a simple model of the impact history of Mars and show that for a variety of impactor types and CO2 surface pressures >0.5 bars, postimpact surface temperatures due to H2 alone can exceed the melting point of water for much longer periods of time than from the dissipation of the heat derived from the impactor's kinetic energy. This longer timescale is set by hydrogen escape rather than radiation to space. Cumulatively, the Noachian surface may have been above the melting point of water for millions of years by this mechanism. These greatly extended postimpact warm environments may have played a larger role in the erosion and mineralogy of the surface than previously thought and may partly explain some of the observed fluvial features.
Seasonal Variations of Titan's Brightness
Authors: Creecy Ellen C. , Li L. , Jiang X. , Nixon C.A. , West R.A. , Kenyon M.E. 
Published: November 2019

AbstractThe absolute brightness of astronomical bodies can be represented by the emitted power, which plays important roles in their radiated energy budgets. The Cassini observations include three seasons of Titan, which provides an unprecedented opportunity to examine the seasonal variations of Titan's emitted power. Our analyses show that Titan's emitted power displays different seasonal behaviors between the Northern Hemisphere and the Southern Hemisphere. The global‐average emitted power decreased by 6.8 ± 0.4% during the Cassini period (2004–2017). Such a temporal variation represents the magnitude of the seasonal cycle of Titan's emitted power, which is at least one order of magnitude stronger than the seasonal variation of Earth's emitted power (<0.5%). More importantly, the ~6.8% decrease of the emitted power is much smaller than the ~18.6% decrease of the solar flux from the change of Sun‐Titan distance, implying a significantly dynamical energy budget on Titan.
The Minimum Scale of Grooving on a Recently Ruptured Limestone Fault
Authors: Okamoto K. K. , Brodsky E. E. , Thom C. A. , Smeraglia L. , Billi A. 
Published: November 2019

AbstractFaults have grooves that are formed by abrasion and wear during slip. Recent observations indicate that this grooving is only a large‐scale feature, indicating brittle behavior has a length scale limit. The connection between this scale and earthquake behavior remains limited because no examples exist from a proven seismogenic fault. Here, we address this problem and analyze differences in this scale between lithologies to further our understanding of the underlying mechanics. This study uses samples from the Mt. Vettoretto fault collected after the Norcia earthquake of 2016. We imaged fault topography with a white light interferometer and 10 μm resolution structure from motion and then calculated a Monte Carlo version of root mean square roughness. We found a minimum scale of grooving of ~100 μm. In comparing this fault to the Corona Heights fault, we find that this minimum grooving scale is consistent with predictions based on material properties.
Increasing Water Vapor in the Stratosphere and Mesosphere After 2002
Authors: Yue Jia , Russell James , Gan Quan , Wang Tao , Rong Pingping , Garcia Rolando , Mlynczak Martin 
Published: November 2019

AbstractWater vapor (H2O) measurements made by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument between 2002 and 2018 and by the Aura Microwave Limb Sounder (MLS) instrument between 2004 and 2018 are analyzed to determine the linear trend and solar cycle response of H2O in the stratosphere and mesosphere. Both SABER and MLS show a rapid global H2O increase of 5–6% per decade in the lower stratosphere after the 2001 drop. The increasing zonal mean H2O at 40°N in SABER and MLS is consistent with the Boulder frost point hygrometer data in the lower stratosphere. The global distribution of SABER and MLS H2O trends are positive at most altitudes and latitudes, and they peak in the tropical lower stratosphere. In the mesosphere the SABER H2O trend is 0.1–0.2 ppmv per decade and the MLS H2O trend is 0.2–0.3 ppmv per decade. The trend and solar cycle response derived from the observations are compared against the Whole Atmosphere Community Climate Model (WACCM). The solar cycle response of H2O from WACCM agrees with SABER and MLS. The linear H2O trend from WACCM does not show the observed increase in the lower stratosphere.
Areal Models for Spatially Coherent Trend Detection: The Case of British Peak River Flows
Authors: Prosdocimi Ilaria , Dupont Emiko , Augustin Nicole H. , Kjeldsen Thomas R. , Simpson Dan P. , Smith Theresa R. 
Published: November 2019

AbstractWith increasing concerns on the impacts of climate change, there is wide interest in understanding whether hydrometric and environmental series display any sort of trend. Many studies however, focus on the analysis of highly variable individual series at each measuring location. We propose a novel and straightforward approach to trend detection, modelling the test statistic for trend at each location via an areal model in which the information across measuring locations is pooled together. We exemplify the method with a detailed study of change in high flows in Great Britain. Using areal models, we detect a statistically relevant signal for a positive trend across Great Britain in the recent decades. This evidence is also found when different temporal subsets of the records are analysed. Further, the model identifies areas where the increase has been higher or lower than average, thus providing a way to prioritise intervention.
Depletion of Heat Producing Elements in the Martian Mantle
Authors: Ojha Lujendra , Karimi Saman , Lewis Kevin W. , Smrekar Suzanne E. , Siegler Matt 
Published: November 2019

AbstractHeat is primarily generated in planetary interiors by the decay of long‐lived heat producing elements (HPE). Planetary heat flow estimates can thus provide critical insights into the thermal state of a planet and the bulk distribution of the HPE. The lack of appreciable lithospheric deflection in the north polar region of Mars by the weight of the polar ice cap is suggestive of low heat flow. Here we model the deflection of the Martian lithosphere and show that the present‐day mantle heat flow cannot exceed 7 mW m−2 in the north polar region of Mars. Our mantle heat flow estimate is notably lower than the heat flow expected from a chondritic mantle suggesting the Martian mantle to be depleted in HPE. If our result is globally representative, lower levels of heat generation in the planet's mantle may have inhibited widespread late‐stage volcanism on Mars.
Convection‐Diffusion Competition Within Mixed Layers of Stratified Natural Waters
Authors: Sepúlveda Steiner Oscar , Bouffard Damien , Wüest Alfred 
Published: November 2019

AbstractIn stratified natural waters, convective processes tend to form nearly homogeneous mixed layers. However, shear‐driven turbulence generated by large‐scale background flow often rapidly smooths them through mixing with the stratified surroundings. Here we studied the effect of background turbulence on convectively driven mixed layers for the case of bioconvection in Lake Cadagno, Switzerland. Along with microstructure measurements, a diffusive‐shape model for the mixed layers allowed us to define (i) mixed layer thickness and (ii) diffusive transition length. Further microstructure analysis was performed allowing estimation of convective turbulence in the mixed layer and shear‐driven turbulence quantified by eddy diffusion in their surroundings. Based upon these results, we propose a Péclet number scaling that relates mixed layer shape to the opposing effects of convection and diffusion. We further validate this quantitative approach by applying it to two other distinct convective systems representative of double‐diffusive convection and radiatively driven under‐ice convection.
Diurnal Cycle of IMERG V06 Precipitation
Authors: Tan Jackson , Huffman George J. , Bolvin David T. , Nelkin Eric J. 
Published: November 2019

AbstractThis study demonstrates the maturing ability of the half‐hourly precipitation estimates from the Integrated Multi‐satellitE Retrievals for GPM (IMERG) for use in global analyses of the diurnal cycle. The refined intercalibration and interpolation between the sensors in V06 leads to greater consistency in the precipitation retrievals over different hours of the day. Evaluation against ground measurements suggests a slight lag in the diurnal phase of only +0.59 hr. We demonstrate the diurnal cycle over different regions around the globe, including the Maritime Continent, where accurate representation of precipitation variability in global models remains a challenge. Using examples over Singapore, Bangladesh, and Lake Victoria, we reveal the intricate interplay between diurnal and seasonal variability. This study demonstrates the unprecedented capability of IMERG in capturing the diurnal cycle of precipitation globally, potentially advancing our understanding in regions of sparse ground measurements and supporting improvements in its representation in global models.
Unprecedented Northern Hemisphere Tropical Cyclone Genesis in 2018 Shaped by Subtropical Warming in the North Pacific and the North Atlantic
Authors: Wang Chao , Wang Bin , Cao Jian 
Published: November 2019

AbstractNorthern Hemisphere tropical cyclone (TC) genesis (TCG) frequency in June‐September of 2018 reached a record high since 1965. This unprecedented TCG was mainly driven by the North Pacific (NP) and the subtropical North Atlantic (NA). TCs in the western North Pacific (WNP) predominately took a northward‐recurving track, resulting in the highest number of named storm days in the subtropical WNP on record. TCs in the eastern North Pacific propagated anomalously westward with three Category 4–5 hurricanes reaching the central North Pacific. The unprecedented TCG in the NP was caused by a persistent weakening of the NP subtropical high that was tightly coupled with the subtropical NP sea surface temperature (SST) warming. In the NA, enhanced TCG was mainly found in the subtropics owing to a favorable large‐scale environment forced by subtropical SST warming. The result here has important implications for understanding variability in TC activity on the hemisphere‐scale.
Looking Up or Looking Down? Hydrologic and Atmospheric Perspectives on Precipitation and Evaporation Variability
Authors: Yin Jun , Porporato Amilcare 
Published: November 2019

AbstractPrecipitation and evapotranspiration, respectively, an input and an output for hydrologists and ocean scientists, but the opposite for meteorologists, quantify the intensity of vertical water exchange between land, ocean, and the atmosphere. The interesting paper by Dagan et al. (2019,https://doi.org/10.1029/2019GL084173) analyzed important constraints between such fluxes as a function of spatial scales. This commentary aims to provide a complementary, hydrologic point of view, emphasizing how their intermittency at different spatial and temporal scales is essentially related to the contrasting water storage capacities of the atmosphere and the Earth's surface. Alterations of such storage due to global warming and land cover change are a challenge for the geophysical community and beyond.
Strong Diffusion of Energetic Electrons by Equatorial Chorus Waves in the Midnight‐to‐Dawn Sector
Authors: Kasahara S. , Miyoshi Y. , Kurita S. , Yokota S. , Keika K. , Hori T. , Kasahara Y. , Matsuda S. , Kumamoto A. , Matsuoka A. , Seki K. , Shinohara I. 
Published: November 2019

AbstractDrastic variations of radiation‐belt/ring current electrons are the result of competing processes of acceleration, transport, and loss. For subrelativistic energetic electrons (10–100 keV), one of the promising loss mechanisms is precipitation into the atmosphere due to pitch angle scattering by whistler mode chorus waves. The efficiency of the scattering has yet to be quantified by direct observations, however. Using in situ measurements by the ERG (Arase) spacecraft in the midnight‐to‐dawn sector at and around the magnetic equator, we demonstrate that the full filling of energetic electron loss cones occurs commonly, associated with typical‐amplitude (greater than 50 pT) chorus waves. The spatial distribution of the loss cone filling indicates that the efficient scattering is limited to |MLAT|< 10°.
Intermodel Spread in the Northern Hemisphere Stratospheric Polar Vortex Response to Climate Change in the CMIP5 Models
Authors: Wu Yutian , Simpson Isla R. , Seager Richard 
Published: November 2019

AbstractThis study investigates the intermodel spread of the Northern Hemisphere winter stratospheric polar vortex change to anthropogenic greenhouse gas increase in Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Previous proposed mechanisms for the polar vortex response to climate change, based on analysis of atmosphere‐only models, are found inadequate to explain the intermodel spread in the coupled models in CMIP5. It is further found that resolved stationary wave driving in the polar vortex region accounts for less than 30% of the intermodel spread, and intermodel differences in both the vertical and meridional wave propagation contribute to differences in the wave driving. The results call for a detailed budget analysis of the stratospheric circulation response by including both the resolved and parameterized processes through the Dynamics and Variability Model Intercomparison Project. The results also highlight a need for an improved theoretical understanding of future projected polar vortex change and intermodel spread.
Morphodynamic Resilience of Intertidal Mudflats on a Seasonal Time Scale
Authors: van der Wegen M. , Roelvink J. A. , Jaffe B. E. 
Published: November 2019

AbstractIntertidal mudflats are morphodynamic features present in many estuaries worldwide. Often located between vegetated shores and deep channels they comprise valuable ecosystems and serve to protect the hinterland by attenuating waves. Although mudflats are persistently present on yearly to decadal time scales, little is known on their morphodynamic adaptation to short‐term variations in forcing such as storms, spring‐neap tidal cycles, and sediment supply. This study aims to explore the morphodynamic resilience of mudflats to seasonal variations in forcing. First, we compare transects observed in South Bay, California, at 3‐ to 6‐monthly intervals. Second, we present the results of a process‐based, morphodynamic profile model (Mflat). Mflat is an open source, Matlab code that describes both cross‐shore and alongshore tidal hydrodynamics as well as a stationary wave model. An advection‐diffusion equation solves sediment transport while bed level changes occur by the divergence of the sediment transport field. Mflat reproduces the observed South San Francisco Bay profile in equilibrium with significant skill. Short‐term variations in hydrodynamic forcing and sediment characteristics disturb the profile mainly at the channel‐shoal edge. The modeled profile disturbance is consistent with observations. The modeled profile is remarkably resilient since it recovers to the equilibrium profile within weeks to months. The model results suggest that 3‐monthly observation intervals are probably too long to discriminate processes responsible for the profile disturbance. These processes may include variations in sediment supply, mudflat erodibility, and wave action as well as the spring‐neap tidal cycle.
Sperm DNA Methylation Epimutation Biomarkers for Male Infertility and FSH Therapeutic Responsiveness
Authors: Luján Saturnino , Caroppo Ettore , Niederberger Craig , Arce Joan-Carles , Sadler-Riggleman Ingrid , Beck Daniel , Nilsson Eric , Skinner Michael K. 
Published: November 2019

AbstractMale factor infertility is increasing and recognized as playing a key role in reproductive health and disease. The current primary diagnostic approach is to assess sperm quality associated with reduced sperm number and motility, which has been historically of limited success in separating fertile from infertile males. The current study was designed to develop a molecular analysis to identify male idiopathic infertility using genome wide alterations in sperm DNA methylation. A signature of differential DNA methylation regions (DMRs) was identified to be associated with male idiopathic infertility patients. A promising therapeutic treatment of male infertility is the use of follicle stimulating hormone (FSH) analogs which improved sperm numbers and motility in a sub-population of infertility patients. The current study also identified genome-wide DMRs that were associated with the patients that were responsive to FSH therapy versus those that were non-responsive. This novel use of epigenetic biomarkers to identify responsive versus non-responsive patient populations is anticipated to dramatically improve clinical trials and facilitate therapeutic treatment of male infertility patients. The use of epigenetic biomarkers for disease and therapeutic responsiveness is anticipated to be applicable for other medical conditions.
Boosting Ultra-Fast Charge Battery Performance: Filling Porous nanoLi4Ti5O12 Particles with 3D Network of N-doped Carbons
Authors: Daigle Jean-Christophe , Asakawa Yuichiro , Beaupré Mélanie , Gariépy Vincent , Vieillette René , Laul Dharminder , Trudeau Michel , Zaghib Karim 
Published: November 2019

AbstractLithium titanium oxide (Li4Ti5O12)-based cells are a promising technology for ultra-fast charge-discharge and long life-cycle batteries. However, the surface reactivity of Li4Ti5O12 and lack of electronic conductivity still remains problematic. One of the approaches toward mitigating these problems is the use of carbon-coated particles. In this study, we report the development of an economical, eco-friendly, and scalable method of making a homogenous 3D network coating of N-doped carbons. Our method makes it possible, for the first time, to fill the pores of secondary particles with carbons; we reveal that it is possible to cover each primary nanoparticle. This unique approach permits the creation of lithium-ion batteries with outstanding performances during ultra-fast charging (4C and 10C), and demonstrates an excellent ability to inhibit the degradation of cells over time at 1C and 45 °C. Furthermore, using this method, we can eliminate the addition of conductive carbons during electrode preparation, and significantly increase the energy density (by weight) of the anode.
Die Hautprävention in der BGN aus medizinischer Perspektive
Authors: Müller M. , Sautter A. , Steen T. , Stadeler M. , Stark U. 
Published: November 2019

ZusammenfassungDer BGN als Unfallversicherungsträger für Beschäftigte im Nahrungsmittel- und Gastgewerbe werden aktuell jährlich etwa 2000 berufsbedingte Hauterkrankungen gemeldet. Beschäftigte in der Gastronomie sind dabei am häufigsten betroffen, gefolgt von Bäckern, Konditoren, Backwarenverkäufern, Beschäftigten im Bereich der Fleischwirtschaft und in der Lebensmittel- und Getränkeindustrie. Als Hauptbelastungsfaktoren für die Haut an Händen und Unterarmen gelten Feuchtarbeit sowie Kontakt zu Nahrungsmitteln. Kumulativ-subtoxische Kontaktdermatitis, atopisches Ekzem und deutlich seltener auch die allergische Kontaktdermatitis sind die häufigsten Primärdiagnosen im Hautarztbericht. Wird seitens der Bezirksverwaltung der BGN ein Heilbehandlungsauftrag erteilt, erfolgt zeitnah ein telefonisches Erstprofiling mit dem Betroffenen. Die Teilnahme an einem eintägigen Haut-Basisseminar wird obligatorisch angeboten. Bei schweren berufsbedingten Hauterkrankungen oder langwierigem, chronisch rezidivierendem Verlauf erfolgt je nach Region die Einbeziehung des beratenden Hautarztes der BGN, die Vorstellung in einem speziellen Hautschutzzentrum, die Teilnahme am regionalen Hautpräventionsprogramm der BGN bzw. eine individuelle Tertiärpräventionsmaßnahme (TIP).
Der Schlaganfall als Risikofaktor für osteoporotische Frakturen
Authors: Benzinger Petra , Bauer Jürgen M 
Published: November 2019

ZusammenfassungIm Rahmen der demographischen Entwicklung in Deutschland nimmt die Zahl der Personen, welche einen Schlaganfall erleiden, stetig zu. Überlebende eines Schlaganfalls haben im Vergleich zur altersgleichen Bevölkerung ein erhöhtes Risiko, eine Fragilitätsfraktur zu erleiden. Für Personen über 65 Jahre mit Schlaganfall wurde eine Inzidenz von 33,6 Frakturen pro 1000 Personenjahre berechnet im Vergleich zu 21,4 pro 1000 Personenjahre in der altersgleichen Bevölkerung. Ursachen sind hier die erhöhte Sturzneigung sowie eine Verminderung der Knochendichte auf der paretischen Seite. Das Risiko für eine sturzbedingte Fraktur ist dabei abhängig von der wiedererlangten Selbständigkeit. Personen mit anhaltendem Pflegebedarf weisen daher ein deutlich erhöhtes Frakturrisiko auf. In Ermangelung einer ausreichenden spezifischen Evidenz für diese Risikogruppe sollten die Empfehlungen zur Sturzprävention für ambulant lebende Menschen berücksichtigt werden. Hier ist insbesondere ein Gleichgewichtstraining in Kombination mit einem Krafttraining anzuraten. Die Indikation zu einer Basisdiagnostik nach DVO Leitlinie sollte unter besonderer Berücksichtigung des Sturzrisikos überprüft werden. Bei Personen mit einer residuellen Hemiparese sollte die DXA Messung auf der paretischen Seite erfolgen.