bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microseismic sources during Hurricane Sandy
Authors: Chen Xiaohan , Tian Dongdong , Wen Lianxing 
Published: August 2015

AbstractWe find that microseisms generated by Hurricane Sandy exhibit coherent energy within 1 h time windows in the frequency band of 0.1–0.25 Hz, but with signals correlated among seismic stations aligned along close azimuths from the hurricane center. With the identification of this signal property, we show that travel time difference can be measured between the correlated stations. These correlated seismic signals can be attributed to two types of seismic sources, with one group of the seismic signals from the hurricane center and the other from coastal region. The seismic sources in coastal region are diffusive and move northward along the coastline as Sandy moves northward. We further develop a hurricane seismic source model, to quantitatively describe the coupling among sea level pressure fluctuations, ocean waves, and solid Earth in the region of hurricane center and determine the evolution of source's strength and pressure fluctuation in the region of hurricane center using seismic data. Strong seismic sources are also identified near the coastal region in New England after Sandy's dissipation, possibly related to subsequent storm surge in the area. The seismic method may be implemented as another practical means for hurricane monitoring, and seismological estimates of the hurricane seismic source model could be used as in situ proxy measurements of pressure fluctuation in the region of hurricane center for hurricane physics studies.
Critical evaluation of state evolution laws in rate and state friction: Fitting large velocity steps in simulated fault gouge with time‐, slip‐, and stress‐dependent constitutive laws
Authors: Bhattacharya Pathikrit , Rubin Allan M. , Bayart Elsa , Savage Heather M. , Marone Chris 
Published: August 2015

AbstractThe variations in the response of different state evolution laws to large velocity increases can dramatically alter the style of earthquake nucleation in numerical simulations. But most velocity step friction experiments do not drive the sliding surface far enough above steady state to probe this relevant portion of the parameter space. We try to address this by fitting 1–3 orders of magnitude velocity step data on simulated gouge using the most widely used state evolution laws. We consider the Dieterich (Aging) and Ruina (Slip) formulations along with a stress‐dependent state evolution law recently proposed by Nagata et al. (2012). Our inversions confirm the results from smaller velocity step tests that the Aging law cannot explain the observed response and that the Slip law produces much better fits to the data. The stress‐dependent Nagata law can produce fits identical to, and sometimes slightly better than, those produced by the Slip law using a sufficiently large value of an additional free parameter c that controls the stress dependence of state evolution. A Monte Carlo search of the parameter space confirms analytical results that velocity step data that are well represented by the Slip law can only impose a lower bound on acceptable values of c and that this lower bound increases with the size of the velocity step being fit. We find that our 1–3 orders of magnitude velocity steps on synthetic gouge impose this lower bound on c to be 10–100, significantly larger than the value of 2 obtained by Nagata et al. (2012) based on experiments on initially bare rock surfaces with generally smaller departures from steady state.
High‐resolution modeling of atmospheric dynamics in the Nepalese Himalaya
Authors: Collier Emily , Immerzeel Walter W. 
Published: August 2015

AbstractHigh‐altitude meteorological processes in the Himalaya are influenced by complex interactions between the topography and the monsoon and westerly circulation systems. In this study, we use the Weather Research and Forecasting model configured with high spatial resolution to understand seasonal patterns of near‐surface meteorological fields and precipitation processes in the Langtang catchment in the central Himalaya. Using a unique high‐altitude observational network, we evaluate a simulation from 17 June 2012 to 16 June 2013 and conclude that, at 1 km horizontal grid spacing, the model captures the main features of observed meteorological variability in the catchment. The finer representation of the complex terrain and explicit simulation of convection at this grid spacing give strong improvements in near‐surface air temperature and small improvements in precipitation, in particular in the magnitudes of daytime convective precipitation and at higher elevations. The seasonal differences are noteworthy, including a reversal in the vertical and along‐valley distributions of precipitation between the monsoon and winter seasons, with peak values simulated at lower altitudes (~3000 m above sea level (asl)) and in the upper regions (above 5000 m asl) in each season, respectively. We conclude that there is great potential for improving the local accuracy of climate change impact studies in the Himalaya by using high‐resolution atmospheric models to generate the forcing for such studies.
Future changes in autumn atmospheric river events in British Columbia, Canada, as projected by CMIP5 global climate models
Authors: Radić Valentina , Cannon Alex J. , Menounos Brian , Gi Nayeob 
Published: August 2015

AbstractAtmospheric rivers (ARs) often trigger extreme precipitation events in British Columbia (BC), Canada. Here we analyze how well the autumn AR events with the highest probability for extreme precipitation over BC, henceforth called AR‐extreme events, are simulated in five Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models (GCMs) and how these AR‐extreme events are projected to change by the end of the century. We examine the daily synoptic patterns of integrated water vapor transport (IVT) over the Pacific Ocean that favor the formation of AR‐extreme events. Our analysis and comparison with AR‐extreme events in four reanalysis products for the period 1979–2010 reveal that the GCMs more successfully resolve their seasonality and interannual variability than their frequencies and amount of precipitation brought to BC. For the CMIP5 scenario's Representative Concentration Pathway (RCP) 4.5 and RCP8.5, the frequency of AR‐extreme events will increase for the period 2070–2100 with the largest increase in December. All models project an increase in total precipitation over BC, due to the increase in frequency and intensity of the AR‐extreme events; however, the dominant factor is the increase in frequency, especially of those events with precipitation exceeding 20 mmd−1. The path of the ARs during the AR‐extreme events is projected to move northward, bringing stronger IVT and more precipitation to the north coast of BC, while the south coast may become drier than at the present day. The shift in the ARs is driven by the northward shift in the Aleutian Low pressure system, especially in RCP8.5.
Trends of ice breakup date in south‐central Ontario
Authors: Fu Congsheng , Yao Huaxia 
Published: August 2015

AbstractLarge‐scale ice phenology studies have revealed overall patterns of later freeze, earlier breakup, and shorter duration of ice in the Northern Hemisphere. However, there have been few studies regarding the trends, including their spatial patterns, in ice phenology for individual waterbodies on a local or small regional scale, although the coherence of ice phenology has been shown to decline rapidly in the first few hundred kilometers. In this study, we extracted trends, analyzed affecting factors, and investigated relevant spatial patterns for ice breakup date time series at 10 locations with record length ≥90 years in south‐central Ontario, Canada. Wavelet methods, including the multiresolution analysis (MRA) method for nonlinear trend extraction and the wavelet coherence (WTC) method for identifying the teleconnections between large‐scale climate modes and ice breakup date, are proved to be effective in ice phenology analysis. Using MRA method, the overall trend of ice breakup date time series (1905–1991) varied from earlier ice breakup to later ice breakup, then to earlier breakup again from south to north in south‐central Ontario. Ice breakup date is closely correlated with air temperature during certain winter/spring months, as well as the last day with snow on the ground and number of snow‐on‐ground days. The influences of solar activity and Pacific North American on ice breakup were comparatively uniform across south‐central Ontario, while those of El Niño–Southern Oscillation, North Atlantic Oscillation, and Arctic Oscillation on ice phenology changed with distance of 50–100 km in the north‐south direction.
Evaluation of global impact models' ability to reproduce runoff characteristics over the central United States
Authors: Giuntoli Ignazio , Villarini Gabriele , Prudhomme Christel , Mallakpour Iman , Hannah David M. 
Published: August 2015

AbstractThe central United States experiences a wide array of hydrological extremes, with the 1993, 2008, 2013, and 2014 flooding events and the 1988 and 2012 droughts representing some of the most recent extremes, and is an area where water availability is critical for agricultural production. This study aims to evaluate the ability of a set of global impact models (GIMs) from the Water Model Intercomparison Project to reproduce the regional hydrology of the central United States for the period 1963–2001. Hydrological indices describing annual daily maximum, medium and minimum flow, and their timing are extracted from both modeled daily runoff data by nine GIMs and from observed daily streamflow measured at 252 river gauges. We compare trend patterns for these indices, and their ability to capture runoff volume differences for the 1988 drought and 1993 flood. In addition, we use a subset of 128 gauges and corresponding grid cells to perform a detailed evaluation of the models on a gauge‐to‐grid cell basis. Results indicate that these GIMs capture the overall trends in high, medium, and low flows well. However, the models differ from observations with respect to the timing of high and medium flows. More specifically, GIMs that only include water balance tend to be closer to the observations than GIMs that also include the energy balance. In general, as it would be expected, the performance of the GIMs is the best when describing medium flows, as opposed to the two ends of the runoff spectrum. With regards to low flows, some of the GIMs have considerably large pools of zeros or low values in their time series, undermining their ability in capturing low flow characteristics and weakening the ensemble's output. Overall, this study provides a valuable examination of the capability of GIMs to reproduce observed regional hydrology over a range of quantities for the central United States.
An improved lightning flash rate parameterization developed from Colorado DC3 thunderstorm data for use in cloud‐resolving chemical transport models
Authors: Basarab B. M. , Rutledge S. A. , Fuchs B. R. 
Published: August 2015

AbstractAccurate prediction of total lightning flash rate in thunderstorms is important to improve estimates of nitrogen oxides (NOx) produced by lightning (LNOx) from the storm scale to the global scale. In this study, flash rate parameterization schemes from the literature are evaluated against observed total flash rates for a sample of 11 Colorado thunderstorms, including nine storms from the Deep Convective Clouds and Chemistry (DC3) experiment in May‐June 2012. Observed flash rates were determined using an automated algorithm that clusters very high frequency radiation sources emitted by electrical breakdown in clouds and detected by the northern Colorado lightning mapping array. Existing schemes were found to inadequately predict flash rates and were updated based on observed relationships between flash rate and simple storm parameters, yielding significant improvement. The most successful updated scheme predicts flash rate based on the radar‐derived mixed‐phase 35 dBZ echo volume. Parameterizations based on metrics for updraft intensity were also updated but were found to be less reliable predictors of flash rate for this sample of storms. The 35 dBZ volume scheme was tested on a data set containing radar reflectivity volume information for thousands of isolated convective cells in different regions of the U.S. This scheme predicted flash rates to within 5.8% of observed flash rates on average. These results encourage the application of this scheme to larger radar data sets and its possible implementation into cloud‐resolving models.
Combined impacts of land cover changes and large‐scale forcing on Southern California summer daily maximum temperatures
Authors: Sequera Pedro , González Jorge E. , McDonald Kyle , Bornstein Robert , Comarazamy Daniel 
Published: August 2015

AbstractCalifornia near‐surface air temperatures are influenced by large‐scale, regional and local factors. In that sense, a numerical model experiment was carried out to analyze the contribution of large‐scale (changes in atmospheric and oceanic conditions) and regional (increased urbanization) factors on the observed California South Coast Air Basin regional summer daily maximum temperature warming pattern from 1950 to 2013. The simulations were performed with past (1950–1954) and present (2009–2013) land cover and climate conditions. The past land cover was derived from historical digital maps, and the present land cover was updated with high‐resolution airborne remote sensing data. Results show that both factors contribute to the total change in daily maximum temperatures. Changes due to large‐scale climate conditions dominate in coastal (due to warming sea surface temperatures) and nonurban regions, while changes due to urbanization have an impact mainly in urban areas, especially inland where large‐scale warming weakens. Increased urbanization has also reduced sea‐breeze intensity due to changes in surface roughness. The model was able to reproduce the regional observed warming pattern, as it incorporates urban heat island effects, otherwise underestimated by large‐scale climate change only.
Effect of climate and land cover changes on watershed runoff: A multivariate assessment for storm water management
Authors: Ekness Paul , Randhir Timothy O. 
Published: August 2015

AbstractImpact of climate change and land use on watershed runoff involves multiattribute ecohydrologic interactions. This information is critical to development of comprehensive storm water management policies. Watersheds in the continental United States have diverse temperatures and precipitation regimes and varying hydrogeomorphic features that influence runoff. This study investigates watershed‐scale runoff using statistical modeling for storm water policy optimization. Multivariate statistical modeling show that vegetative activity, annual evaporation, precipitation, temperature, and soil moisture significantly influenced watershed runoff. Soil moisture has a strong influence on runoff with each percent increase causing 5% increase in runoff. Nonlinear modeling with quadratic and interaction effects shows a significant interaction between soil moisture and other climatic variables in influencing annual runoff patterns. Changes in climate affect ecohydrologic characters by altering available soil moisture, evaporation, precipitation patterns, and runoff. Optimization of green infrastructure design can be a successful management tool for runoff with an understanding that changes to multiple attributes in ecohydrologic variables affect runoff. Multi‐attribute‐based green infrastructure and incentive policies can result in comprehensive storm water policies that incorporate climatic and ecohydrologic conditions of watershed systems.
New method for deriving the topside ionospheric Vary‐Chap scale height
Authors: Wang Sicheng , Huang Sixun , Fang Hanxian 
Published: August 2015

AbstractAn α‐Chapman function with a continuously varying scale height H(h) can be used to describe the topside ionosphere electron density profile that seamlessly connects the ionosphere with the plasmasphere. Huang and Reinisch () have derived the analytic expression of the scale height from the Vary‐Chap function, which can be applied to the topside F2 region. However, the H(h) is still difficult to obtain because H(h) is a function of the unknown value H(h) at hmF2. In this paper, the maximum entropy method is introduced to solve this ill‐posed problem, and the Vary‐Chap scale height for each electron density profile is derived. Then the average percentage errors that defined as the differences between the measured electron density profiles and the Vary‐Chap profiles obtained from the Vary‐Chap scale heights are calculated with the Alouette/ISIS satellites topside sounder database. The results reveal that the average percentage errors are generally less than 5% and the Vary‐Chap profiles can well represent the topside electron density profiles. What is more, the local time, seasonal, solar cycle, and latitudinal variations of the Vary‐Chap scale height are preliminarily analyzed.
Syntrophobacter
Authors: McInerney Michael J. , Stams Alfons J.M. , Boone David R. 
Published: August 2015

Syn.tro.pho.bac' ter. Gr. adj.syntogether with; Gr. n.trophosone who feeds; M.L. n.bactermasc. equivalent of Gr. neut. n.bacterionsmall staff, rod; M.L. masc. n.Syntrophobacterrod which feeds together with (another species).Proteobacteria / Deltaproteobacteria / Syntrophobacterales / Syntrophobacteraceae / SyntrophobacterStraight rods with rounded ends, 0.6–1.2 × 1.0–4.5 µm, sometimes oval to ellipsoid, occur singly and in pairs. May form short chains and filamentous cells (up to 35 µm).Gram negative. Endospores not formed.Strictly anaerobic chemoorganotroph. Mesophilic. Growth occurs at neutral pH (6.2–8.0) in low salinity media.Growth occurs by syntrophic metabolism and sulfate reduction. Propionate oxidation to acetate and CO2requires the presence of either a H2/formate‐using organism (methanogen or sulfate reducer) or sulfate as the electron acceptor.Acetate and other fatty acids not oxidized. Some species grow fermentatively with pyruvate, malate, or fumarate. Lactate and propanol may serve as electron donors for syntrophic metabolism or sulfate reduction.Other common bacterial substrates such as sugars and aromatic compounds are not usedeither in coculture with a H2/formate‐using organism or in pure culture with sulfate as the electron acceptor. Sulfite or thiosulfate, but not nitrate, may be used as the electron acceptor. Habitat is sludge from anaerobic waste treatment facilities.The mol%G+C of the DNA is: 57–61.Type species:Syntrophobacter woliniiBoone and Bryant 1984, 355 (Effective publication: Boone and Bryant 1980, 631.)
Thiodictyon
Authors: Imhoff Johannes F. 
Published: August 2015

Thi' o.dic' ty.on. Gr. n.thiossulfur; Gr. n.dictyona net; M.L. neut. n.Thiodictyonsulfur net.Proteobacteria / Gammaproteobacteria / Chromatiales / Chromatiaceae / ThiodictyonCells are rod shaped with rounded ends, sometimes appearing spindle‐shaped, multiply by binary fission,nonmotile under all conditions, may form aggregates in which the cells are arranged end‐to‐end in an irregular netlike structure, the shape of which is variable. May also form clumps that are more compact or break up into individual cells. Contain large,irregularly shaped gas vesiclesin the central part of the cell. Gram negative, belong to theGammaproteobacteria, and contain internalphotosynthetic membranes of vesicular typewith bacteriochlorophyllaand carotenoids as photosynthetic pigments.The mol%G+C of the DNA is: 65.3–66.3.Type species:Thiodictyon elegansWinogradsky 1888x, 82.
Proteus
Authors: Penner John L. 
Published: August 2015

Pro' te.us. Gr. n.Proteusan ocean god able to change himself into different shapes.Proteobacteria / Gammaproteobacteria / Enterobacteriales / Enterobacteriaceae / ProteusStraight rods, 0.4–0.8 × 1.0–3.0 μm. Gram negative.Motileby peritrichous flagella.Most strains swarm with periodic cycles of migration producing concentric zones, or spread in a uniform film, over moist surfaces solidified with agar or gelatin. The organisms in this genus conform to the definition of the familyEnterobacteriaceae.They are facultatively anaerobic, chemoorganotrophic, having both a respiratory and a fermentative type of metabolism. Optimal growth temperature is 37°C.Oxidase negative; catalase positive. Methyl red positive; species vary in indole production, Voges–Proskauer, and Simmons citrate tests. They oxidatively deaminate phenylalanine and tryptophan. Urea is hydrolyzed. Lysine decarboxylase negative and arginine dihydrolase negative; onlyProteus mirabilisdecarboxylates ornithine. All butProteus myxofaciensdecompose tyrosine to produce a clearing on agar media in which the insoluble amino acid is incorporated. Grow on KCN. H2S is usually produced. Malonate is not utilized.D‐glucose and a few other carbohydrates are catabolized with production of acid and usually gas. Does not produce acid from inositol or from straight chain tetra‐, penta‐, or hexahydroxy—alcohols, but generally produces acid from glycerol. One or more species ferment maltose, sucrose, trehalose, andD‐xylose. Human pathogens, causing urinary tract infections; also are secondary invaders, causing septic lesions at other sites of the body. Occurs in the intestines of humans and a wide variety of animals; also occurs in manure, soil, and polluted waters.P. myxofacienshas been isolated only from gypsy moth larvae. Based on 16S rDNA sequence analysis,Proteusbelongs to the familyEnterobacteriaceaewithin theProteobacteria(Woese et al., 1985; Niebel et al., 1987; Stackebrandt et al., 1988).The mol%G+C of the DNA is: 38–41 (Falkow et al., 1962).Type species:Proteus vulgarisHauser 1885, 12 emend. Brenner, Hickman‐Brenner, Holmes, Hawkey, Penner, Grimont and O'Hara 1995, 870.
Shigella
Authors: Strockbine Nancy A. , Maurelli Anthony T. 
Published: August 2015

Shi.gel' la. M.L. dim. ‐ellaending; M.L. fem. n.Shigellanamed after K. Shiga, the Japanese bacteriologist who first discovered the dysentery bacillus.Proteobacteria / Gammaproteobacteria / Enterobacteriales / Enterobacteriaceae / ShigellaStraight rods, 1–3 × 0.7–1.0 µm, that conform to the general definition of the familyEnterobacteriaceaeand contain the enterobacterial common antigen. Gram negative. Nonmotile. Non‐pigmented. Facultatively anaerobic, having both a respiratory and a fermentative type of metabolism. Catalase positive (with exceptions inShigella dysenteriae). Oxidase negative. Chemoorganotrophic.Ferment sugars without gas production(a few exceptions produce gas).Salicin, adonitol, andmyo‐inositol are not fermented. Strains ofShigella sonneiferment lactose and sucrose upon extended incubation; however, other species do not utilize these substances in conventional medium.Do not utilize citrate, malonate, or sodium acetate(with exceptions inShigella flexnerifor sodium acetate) as a sole carbon source.Do not grow in KCN or produce H2S. Do not decarboxylate lysine. Reduce nitrates to nitrites. Intestinal pathogens of humans and other primates, causing bacillary dysentery. Based on 16S rDNA sequencing, shigellae belong in theGammaproteobacteria.The mol%G+C of the DNA is: 49–53 (Laskin and Lechevalier, 1981).Type species:Shigella dysenteriae(Shiga 1898) Castellani and Chalmers 1919, 935, Epit. Spec. Cons. Opinion 11 of the Jud. Comm. 1954a, 149 (Bacillus dysenteriaeShiga 1898, 817.)