bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction between El Niño and Extreme Indian Ocean Dipole
Authors: Luo Jing-Jia , Zhang Ruochao , Behera Swadhin K. , Masumoto Yukio , Jin Fei-Fei , Lukas Roger , Yamagata Toshio 
Published: September 2009

Abstract
Climate variability in the tropical Indo-Pacific sector has undergone dramatic changes under global ocean warming. Extreme Indian Ocean dipole (IOD) events occurred repeatedly in recent decades with an unprecedented series of three consecutive episodes during 2006–08, causing vast climate and socioeconomic effects worldwide and weakening the historic El Niño–Indian monsoon relationship. Major attention has been paid to the El Niño influence on the Indian Ocean, but how the IOD influences El Niño and its predictability remained an important issue to be understood. On the basis of various forecast experiments activating and suppressing air–sea coupling in the individual tropical ocean basins using a state-of-the-art coupled ocean–atmosphere model with demonstrated predictive capability, the present study shows that the extreme IOD plays a key role in driving the 1994 pseudo–El Niño, in contrast with traditional El Niño theory. The pseudo–El Niño is more frequently observed in recent decades, coincident with a weakened atmospheric Walker circulation in response to anthropogenic forcing. The study’s results suggest that extreme IOD may significantly enhance El Niño and its onset forecast, which has being a long-standing challenge, and El Niño in turn enhances IOD and its long-range predictability. The intrinsic El Niño–IOD interaction found here provides hope for enhanced prediction skill of both of these climate modes, and it sheds new light on the tropical climate variations and their changes under the influence of global warming.
Impact of Common Sea Surface Temperature Anomalies on Global Drought and Pluvial Frequency
Authors: Findell Kirsten L. , Delworth Thomas L. 
Published: September 2009

Abstract
Climate model simulations run as part of the Climate Variability and Predictability (CLIVAR) Drought Working Group initiative were analyzed to determine the impact of three patterns of sea surface temperature (SST) anomalies on drought and pluvial frequency and intensity around the world. The three SST forcing patterns include a global pattern similar to the background warming trend, a pattern in the Pacific, and a pattern in the Atlantic. Five different global atmospheric models were forced by fixed SSTs to test the impact of these SST anomalies on droughts and pluvials relative to a climatologically forced control run.
The five models generally yield similar results in the locations of drought and pluvial frequency changes throughout the annual cycle in response to each given SST pattern. In all of the simulations, areas with an increase in the mean drought (pluvial) conditions tend to also show an increase in the frequency of drought (pluvial) events. Additionally, areas with more frequent extreme events also tend to show higher intensity extremes. The cold Pacific anomaly increases drought occurrence in the United States and southern South America and increases pluvials in Central America and northern and central South America. The cold Atlantic anomaly increases drought occurrence in southern Central America, northern South America, and central Africa and increases pluvials in central South America. The warm Pacific and Atlantic anomalies generally lead to reversals of the drought and pluvial increases described with the corresponding cold anomalies. More modest impacts are seen in other parts of the world. The impact of the trend pattern is generally more modest than that of the two other anomaly patterns.
The Physical Mechanisms by Which the Leading Patterns of SST Variability Impact U.S. Precipitation
Authors: Wang Hailan , Schubert Siegfried , Suarez Max , Koster Randal 
Published: September 2009

Abstract
This study uses the NASA Seasonal-to-Interannual Prediction Project (NSIPP-1) AGCM to investigate the physical mechanisms by which the leading patterns of annual mean SST variability impact U.S. precipitation. The focus is on a cold Pacific pattern and a warm Atlantic pattern that exert significant drought conditions over the U.S. continent. The precipitation response to the cold Pacific is characterized by persistent deficits over the Great Plains that peak in summer with a secondary peak in spring, and weakly pluvial conditions in summer over the Southeast (SE). The precipitation response to the warm Atlantic is dominated by persistent deficits over the Great Plains with the maximum deficit occurring in late summer. The precipitation response to the warm Atlantic is overall similar to the response to the cold Pacific with, however, considerably weaker amplitude.
An analysis of the atmospheric moisture budget combined with a stationary wave model diagnosis of the associated atmospheric circulation anomalies is conducted to investigate mechanisms of the precipitation responses. A key result is that, while the cold Pacific and warm Atlantic are two spatially distinct SST patterns, they nevertheless produce similar diabatic heating anomalies over the Gulf of Mexico during the warm season. In the case of the Atlantic forcing, the heating anomalies are a direct response to the SST anomalies, whereas in the case of Pacific forcing they are a secondary response to circulation anomalies forced from the tropical Pacific. The diabatic heating anomalies in both cases force an anomalous low-level cyclonic flow over the Gulf of Mexico that leads to reduced moisture transport into the central United States and increased moisture transport into the eastern United States. The precipitation deficits over the Great Plains in both cases are greatly amplified by the strong soil moisture feedback in the NSIPP-1 AGCM. In contrast, the response over the SE to the cold Pacific during spring is primarily associated with an upper-tropospheric high anomaly over the southern United States that is remotely forced by tropical Pacific diabatic heating anomalies, leading to greatly reduced stationary moisture flux convergences and anomalous subsidence in that region. Moderately reduced evaporation and weakened transient moisture flux convergences play secondary roles. It is only during spring that these three terms are all negative and constructively contribute to produce the maximum dry response in spring.
The above findings based on the NSIPP-1 AGCM are generally consistent with observations, as well as with four other AGCMs included in the U.S. Climate Variability and Predictability (CLIVAR) project.
Subduction on the Northern and Southern Flanks of the Gulf Stream
Authors: Thomas Leif N. , Joyce Terrence M. 
Published: September 2009

Abstract
Sections of temperature, salinity, dissolved oxygen, and velocity were made crossing the Gulf Stream in late January 2006 to investigate the role of frontal processes in the formation of Eighteen Degree Water (EDW), the Subtropical Mode Water of the North Atlantic. The sections were nominally perpendicular to the stream and measured in a Lagrangian frame by following a floating spar buoy drifting in the Gulf Stream’s warm core. During the survey, EDW was isolated from the mixed layer by the stratified seasonal pycnocline, suggesting that EDW was not yet actively being formed at this time in the season and at the longitudes over which the survey was conducted (64°–70°W). However, in two of the sections, the seasonal pycnocline in the core of the Gulf Stream was broken by an intrusion of cold, fresh, weakly stratified water, nearly saturated in oxygen, that appears to have been subducted from the surface mixed layer north of the stream. The intrusion was identified in three of the sections in profiles with a nearly identical temperature–salinity relation. From the western-to-easternmost sections, where the intrusion was observed, the depth of the intrusion’s salinity minimum descended by ∼90 m in the 71 h it took to complete this part of the survey. This apparent subduction occurred primarily on the upstream side of a meander trough, where the cross-stream velocity was confluent and frontogenetic. Using a variant of the omega equation, the vertical velocity driven by the confluent flow was inferred and yielded downwelling in the vicinity of the intrusion spanning 10–40 m day−1, a range of values consistent with the intrusion’s observed descent, suggesting that frontal subduction was responsible for the formation of the intrusion. In the easternmost section located downstream of the meander trough, the flow was diffluent, driving an inferred vertical circulation that was of the opposite sense to that in the section upstream of the trough. In transiting the two sides of the trough, the intrusion was observed to move toward the center of the stream between the downwelling branches of the opposing vertical circulations, resulting in a downward Lagrangian mean vertical velocity and net subduction. Hydrographic evidence of the subduction of weakly stratified surface waters was seen in the southern flank of the Gulf Stream as well. The solution of the omega equation suggests that this subduction was associated with a relatively shallow vertical circulation confined to the upper 200 m of the water column in the proximity of the front marking the southern edge of the warm core.
Upper-Ocean Processes under the Stratus Cloud Deck in the Southeast Pacific Ocean
Authors: Zheng Yangxing , Kiladis George N. , Shinoda Toshiaki , Metzger E. Joseph , Hurlburt Harley E. , Lin Jialin , Giese Benjamin S. 
Published: September 2009

Abstract
The annual mean heat budget of the upper ocean beneath the stratocumulus/stratus cloud deck in the southeast Pacific is estimated using Simple Ocean Data Assimilation (SODA) and an eddy-resolving Hybrid Coordinate Ocean Model (HYCOM). Both are compared with estimates based on Woods Hole Oceanographic Institution (WHOI) Improved Meteorological (IMET) buoy observations at 20°S, 85°W. Net surface heat fluxes are positive (warming) over most of the area under the stratus cloud deck. Upper-ocean processes responsible for balancing the surface heat flux are examined by estimating each term in the heat equation. In contrast to surface heat fluxes, geostrophic transport in the upper 50 m causes net cooling in most of the stratus cloud deck region. Ekman transport provides net warming north of the IMET site and net cooling south of the IMET site. Although the eddy heat flux divergence term can be comparable to other terms at a particular location, such as the IMET mooring site, it is negligible for the entire stratus region when area averaged because it is not spatially coherent in the open ocean. Although cold-core eddies are often generated near the coast in the eddy-resolving model, they do not significantly impact the heat budget in the open ocean in the southeast Pacific.
Feasibility of Cloud Screening Using Proxy Photon Pathlength Distributions Derived from High-Resolution Spectra in the Near Infrared
Authors: O’Brien D. M. , Polonsky Igor , Stephens Philip , Taylor Thomas E. 
Published: September 2009

Abstract
High-resolution spectra of reflected sunlight in the 2-μm absorption band of CO2 are simulated at the top of the atmosphere using cloud profiles and particle sizes from CloudSat analyzed meteorology from ECMWF, surface bidirectional distribution functions over land derived from the Moderate Resolution Imaging Spectroradiometer (MODIS), and a facet model of ocean reflectance. It is argued that in clear sky the photons will follow the direct path from sun to surface to satellite, because Rayleigh scattering is negligible at 2 μm, so the distribution of photon pathlengths will be a δ function. A proxy for the photon pathlength distribution under any sky condition is recovered from the high-resolution spectrum by representing the distribution as a weighted sum of δ functions. Scenes are classified as clear or cloudy according to how closely the distribution approximates the ideal single δ function for the direct path. The algorithm has an efficiency of approximately 75%, meaning that 25% of the clear cases will be rejected as cloudy. For scenes that pass the clear-sky test, the probability that the prediction will be correct is typically 95%. The algorithm appears to be robust, insensitive to instrument noise and to errors in the surface pressure and profiles of temperature and water vapor. The efficiency and confidence level of the algorithm are almost unchanged for bright surfaces such as sun glint.
The Diurnal Cycle of Winds, Rain, and Clouds over Taiwan during the Mei-Yu, Summer, and Autumn Rainfall Regimes
Authors: John Kerns Brandon Wesley , Chen Yi-Leng , Chang Mei-Yu 
Published: September 2009

Abstract
The diurnal variations in surface winds, rain, and clouds over Taiwan are presented for three rainfall regimes: the mei-yu (16 May–15 June), summer (16 July–31 August), and autumn (16 September–15 October). Though the magnitude of diurnal island divergence and convergence is similar under each regime, the diurnal variations of rain and clouds vary considerably between the regimes. These differences are related to the seasonal changes in environment winds, stability, moisture, and weather systems. In addition to orographic lifting on the windward side, rainfall occurrences for all three rainfall regimes are strongly modulated by the diurnal heating cycle with an afternoon maximum. The largest day–night differences in rainfall occur in summer and the smallest differences occur in autumn. The upper-level high cloud (&lt;235 K) frequencies have a pronounced afternoon maximum over the mountainous areas in the afternoon because of combined effects of orographic lifting and solar heating. These clouds are advected downstream by the upper-level winds in late afternoon and early evening. The highest afternoon high cloud frequencies occur in summer (&gt;30%) with the lowest upper-level cloud cover in autumn (∼10%). In autumn, most of the orographic showers on the eastern and northeastern windward side in the late afternoon and early evening are not from deep clouds. The weak early-morning rainfall maxima for all three seasons are related to the localized boundary layer convergence due to the orographic blocking of the prevailing winds and their interactions with the offshore/land breeze. During disturbed, prefrontal periods in the mei-yu, bands of high clouds and rain tend to develop in the early morning in the convergence zone off the northwest coast. These rainbands are responsible for the early-morning rainfall maximum on the northwest coast. They do not occur in summer or autumn.
Advances in Predicting Continental Low Stratus with a Regional NWP Model
Authors: Kann Alexander , Seidl Harald , Wittmann Christoph , Haiden Thomas 
Published: September 2009

Abstract
In the eastern Alpine region, subinversion cloudiness associated with elevated temperature inversions is a frequent phenomenon in autumn and winter, which often persists for several days. Although the prediction of fog and low stratus by numerical weather prediction (NWP) models has improved in recent years, these models still show deficiencies in the spatial and temporal evolution of such wintertime weather phenomena. In spite of sophisticated current assimilation schemes or simply due to unknown conditions, even the analysis shows large discrepancies compared to the true atmospheric state. Inversions are often “smeared out” and the moist layer below the inversion is too far from saturation. Model integration from such an initial state leads to strong biases in the total cloudiness and, due to erroneous radiative response, in 2-m temperature forecasts. In the present paper, an empirical enhancement scheme for subinversion cloudiness is introduced within the framework of Aire Limitée Adaptation Dynamique Développement International (ALADIN), the operational limited area model (LAM) at the Austrian Central Institute for Meteorology and Geodynamics (ZAMG). The scheme attempts to compensate for model deficiencies in the vertical temperature and humidity profiles in order to enhance or keep preexisting signals of inversions and associated low cloudiness. Thus, a positive feedback due to radiative reaction is activated, which finally leads to more realistic vertical profiles, low (and total) cloudiness, and improved 2-m temperature predictions. Case studies demonstrate the impacts of the scheme on predictions of the spatial distribution of low cloudiness and on the vertical profiles of temperature and humidity. Verification over stratus episodes within a 2-month period comparing a reference model run without the scheme with a modified model version with the subinversion cloudiness scheme confirms the ability of the scheme to improve stratus-related wintertime weather prediction.
225Ac Metallofullerene: Toward 225Ac Nanogenerator in Fullerene
Authors: Akiyama Kazuhiko , Haba Hiromitsu , Sueki Keisuke , Tsukada Kazuaki , Asai Masato , Toyoshima Atsushi , Nagame Yuichiro , Katada Motomi 
Published: September 2009

Abstract
We report on the successful production of a metallofullerene encapsulating the radioactive tracer 225Ac and on its electronic properties studied by radiochromatography. Considering the number of π electrons on the fullerene cage estimated from the HPLC retention time on the 5PBB column and the general oxidation state of Ac(III), the chemical species of the dominant chromatographic peak is suggested to be Ac@C82.
Crystallographic Study of Superelastic Deformation of Nitinol
Authors: Wu Ming H. , Gong Xiao-Yan , Mao Shengcheng , Han Xiaodong 
Published: September 2009

Abstract
Limitations of finite element analysis (FEA) in providing accurate localized stress and strain information in superelastic nitinol are well recognized. Understanding the parent texture and the crystallography of stress-induced martensitic transformation holds the key to bridge the gap between continuum mechanics and the microscopic stress-strain condition imposed by the phase transformation in understanding the deformation mechanism of this complex material. A scanning electron microscope equipped with an electron beam back scatter diffraction detector is a powerful tool that can extract microscopic crystallographic information from bulk specimens. The technique has been employed to study the crystallography of stress-induced martensitic transformation during tensile and bend deformations of superelastic nitinol. The results suggest that for tensile deformation, the transformation variants of stress-induced martensite (SIM) inside the Lüders band follow maximum shear stress along the martensite shape change direction. The observation also confirms that the SIM transformation is incomplete, leaving a significant amount of retained B2 parent phase inside the Lüders band. As tensile deformation proceeds, the Lüders band propagates by nucleating new martensite plates instead of by thickening of the existing martensite variants. For bend deformation, SIM appears to transform much easier in the tension side than in the compression side, confirming previous studies on the asymmetrical tension-compression property in superelastic nitinol materials. Lastly, the local stress field at the tip of martensite plate has been computed by finite element (FEA) simulation based on the observed martensite morphology. The implication on local stress field and plasticity provides a rationalization in explaining why nitinol fatigue life appears to be insensitive to the mean strain effect.
Masonry
Authors: Trimble Brian E. , Brisch Joseph H. 
Published: September 2009

Description
Thirteen peer-reviewed papers cover the latest information on all aspects of masonry materials, design, specification, construction, maintenance and rehabilitation.
Topics cover:
• Glazed brick cladding
• Analyzing hardened masonry mortars
• Masonry beams
• Stone adhered veneer
• Concrete masonry walls
• Brick masonry
• And much more!
Development and Application of the PRL Single-Pass Capillary Viscometer
Authors: Klaus E. Erwin , Angeloni Francis M. , Fenske Merrell R. 
Published: September 2009

The design and construction of a versatile capillary high-shear viscometer is described. Use of nitrogen pressure as the driving force and of a single pass through the capillary completely eliminate all areas of nonstreamline flow from the viscometer. By using interchangeable capillaries and efflux bulbs, the viscometer has a temperature range of -65 to 300 F, a viscosity range of S to 1 million centipoises, and a rate-of-shear range of 1 to 1 million reciprocal seconds. The maximum shearing stress for the three capillaries described varies from 92,000 to 300,000 dynes per sq cm.
Calibration techniques with Newtonian hydrocarbon fluids are described. Temperature and pressure effects of both Newtonian hydrocarbons and non-Newtonian polymer solutions are evaluated in capillary instruments.
Non-Newtonian data for the PRL (Petroleum Refining Laboratory) single-pass viscometer, using ASTM oils 103 and 104, are compared with similar data for the Kingsbury tapered plug viscometer and for the PRL high-shear viscometer.
High-shear-rate viscosity measurement of polymer solutions without permanent viscosity change is demonstrated. The effects of polymer type, polymer molecular weight, and solvent type are illustrated, using the PRL single-pass viscometer.
Air, Soil, and Sea Galvanic Corrosion Investigation at Panama Canal Zone
Authors: Pelensky M. A. , Jaworski J. J. , Gallaccio A. 
Published: September 2009

Various combinations of metals are used widely in military and industrial equipment. Many of these are deployed worldwide and in many situations under aggressive natural environmental conditions. The object of this study and this paper relates to the effects of subtropical environment on coupled, dissimilar structural metals of military interest. These include aluminum, brass, magnesium, Monel, steel, stainless steel, and titanium alloys. The environments are the atmosphere at Fort Sherman, soil (burial) at Fort Sherman, and seawater (total immersion) at Coco Solo, Panama Canal Zone. Results of this study should have significance in the selection of materials for design of equipment for use in these environments. The atmospheric specimens are rectangular, directly coupled, and offsetted. Offsetting was employed since this would lead to variability in galvanic effects over the exposed surfaces and edges. End grain attack, particularly at the edges of the tempered and aged light alloys, is of interest. For soil burial and seawater immersion, cylindrical specimens connected through a polyacrylate resin cylinder were used. These were selected as suitable and convenient for this purpose.
The atmospheric specimens were placed at site in April 1973, and the soil and seawater specimens were located during Oct. 1973. Atmospheric tests are expected to continue for a total period of four years and soil, five years; seawater tests are likely to continue for a total of three and one half years.
Atmospheric, soil, and seawater specimens are returned to the laboratory periodically during the test for examination and weight loss determination to assess the effects of each of the environments on the various galvanic couple combinations.
Only limited results are available at this early stage of the investigation. Accordingly, no final determination can be made at this time of the significance of results.