bluuebunny/crossref_metadata_2025_split huggingface dataset:
Re-Visiting the Implications of Contemporary Epistemological Models for the Understanding of Religious Experience: an Overview
Authors: Veldsman Daniel P. 
Published: June 2008

AbstractThe more recently proposed epistemological models (cf Gregersen & Van Huyssteen, eds., Rethinking Theology and Science: Six Models for the Current Dialogue) within the context of the science and religion debate, have opened up galaxie,s of meanirzg on the interface of the debates which are inviting for exploralive, theological travelling. But how are we epistemologically to judge not only oui journets but also the rethinking of the implications of these epistemological models for our understanding of religious experience and our experience of transcendence? The interdisciplinary space that has been opened up in an exciting post-foundational manner zuithirz these very debates, leaves us as rational persons, embedded in a very specific social and historical context, with the haunting cognitive pluralist question on how to reach beyond the limits of our own epistemic traditions (Wentzel van Huyssteen). This question is pursued as an effort on the one hand to unmask epistemic arrogance and, on the other hand, not to take refuge in the insular comfort of internally closed language-systems. It is an effort to address relativism and a 'twentieth-century despair of any knozuledye of reality' (Polkinghorne). It is finally an effort to conceptually revisit the implications of tltese models for our understanding of our culturally embedded religious experience.
Composite Predictor Maps of Extraordinary Weather Events in the Sacramento, California, Region*
Authors: Grotjahn Richard , Faure Ghislain 
Published: June 2008

Abstract
Extraordinary weather events in the Sacramento, California, region are examined using a simple compositing technique. The extraordinary events identified are uncommon and the worst of their kind, but not necessarily severe. While the criteria outlined herein are drawn from Sacramento weather station data, the identified events are extraordinary elsewhere over much, if not all, of California’s Central Valley. Several types of extraordinary events are highlighted, including the hardest freezes, heaviest prolonged rain events, longest-duration fog, and worst heat waves (onset and end) in a 21-yr period. Bootstrap resampling establishes the statistical significance of features on the composite maps. The composite maps with statistically significant features highlighted allow a forecaster to search for key features in forecast maps that coexist with or that precede an extraordinary weather event. Local- and regional-scale extraordinary events have larger-scale signatures that can be traced back in time. Many of these features are intuitive and known to local forecasters (and that provides a check upon the methodology used here). However, some features appear to be unexpected. For example, a ridge (in height and thermal fields) over the southeastern United States generally occurs prior to the worst heat waves and hardest freezes. Some features appear to exhibit the theoretical concept of downstream development. Several extraordinary weather types are preceded by a ridge either over Alaska (hardest freezes and heaviest prolonged rain) or just west of Alaska (worst heat waves). While the Alaskan ridge passes a significance test, the presence of other features (such as the southeastern ridge) determines what, if any, extraordinary event occurs near Sacramento. However, a feature that passes the significance test for the composite might not occur in every member of a given extraordinary event. The height and thermal patterns over the West Coast and North Pacific are similar for summer’s worst heat waves and winter’s longest-duration fog: both types of events are preceded by a trough in the eastern mid-Pacific.
Using Precipitation Observations in a Mesoscale Short-Range Ensemble Analysis and Forecasting System
Authors: Fujita Tadashi , Stensrud David J. , Dowell David C. 
Published: June 2008

Abstract
A simple method to assimilate precipitation data from a synthesis of radar and gauge data is developed to operate alongside an ensemble Kalman filter that assimilates hourly surface observations. The mesoscale ensemble forecast system consists of 25 members with 30-km grid spacing and incorporates variability in both initial and boundary conditions and model physical process schemes. The precipitation assimilation method only incorporates information on when and where rainfall is observed. Model temperature and water vapor mixing ratio profiles at each grid point are modified if rainfall is observed but not predicted, or if rainfall is predicted but not observed. These modifications act to either increase or decrease, respectively, the likelihood that precipitation develops at that grid point.
Two cases are examined in which this technique is applied to assimilate precipitation data every 15 min from 1200 to 1800 UTC, while hourly surface observations are also assimilated at the same time using the more sophisticated ensemble Kalman filter approach. Results show that the simple method for assimilating precipitation data helps the model develop precipitation where it is observed, resulting in the precipitation area being reproduced more accurately than in the run without precipitation-data assimilation, while not negatively influencing the positive results from the surface data assimilation. Improvement is also seen in the reliability of precipitation probabilities for a 1 mm h−1 threshold after the assimilation period, indicating that assimilating precipitation data may provide improved forecasts of the mesoscale environment for a few hours.
Experiences with 0–36-h Explicit Convective Forecasts with the WRF-ARW Model
Authors: Weisman Morris L. , Davis Christopher , Wang Wei , Manning Kevin W. , Klemp Joseph B. 
Published: June 2008

Abstract
Herein, a summary of the authors’ experiences with 36-h real-time explicit (4 km) convective forecasts with the Advanced Research Weather Research and Forecasting Model (WRF-ARW) during the 2003–05 spring and summer seasons is presented. These forecasts are compared to guidance obtained from the 12-km operational Eta Model, which employed convective parameterization (e.g., Betts–Miller–Janjić). The results suggest significant value added for the high-resolution forecasts in representing the convective system mode (e.g., for squall lines, bow echoes, mesoscale convective vortices) as well as in representing the diurnal convective cycle. However, no improvement could be documented in the overall guidance as to the timing and location of significant convective outbreaks. Perhaps the most notable result is the overall strong correspondence between the Eta and WRF-ARW guidance, for both good and bad forecasts, suggesting the overriding influence of larger scales of forcing on convective development in the 24–36-h time frame. Sensitivities to PBL, land surface, microphysics, and resolution failed to account for the more significant forecast errors (e.g., completely missing or erroneous convective systems), suggesting that further research is needed to document the source of such errors at these time scales. A systematic bias is also noted with the Yonsei University (YSU) PBL scheme, emphasizing the continuing need to refine and improve physics packages for application to these forecast problems.
Use of Normalized Anomaly Fields to Anticipate Extreme Rainfall in the Mountains of Northern California
Authors: Junker Norman W. , Grumm Richard H. , Hart Robert , Bosart Lance F. , Bell Katherine M. , Pereira Frank J. 
Published: June 2008

Abstract
Extreme rainfall events contribute a large portion of wintertime precipitation to northern California. The motivations of this paper were to study the observed differences in the patterns between extreme and more commonly occurring lighter rainfall events, and to study whether anomaly fields might be used to discriminate between them. Daily (1200–1200 UTC) precipitation amounts were binned into three progressively heavier categories (12.5–50.0 mm, light; 50–100 mm, moderate; and &gt;100 mm, heavy) in order to help identify the physical processes responsible for extreme precipitation in the Sierra Nevada range between 37.5° and 41.0°N.
The composite fields revealed marked differences between the synoptic patterns associated with the three different groups. The heavy composites showed a much stronger, larger-scale, and slower-moving negative geopotential height anomaly off the Pacific coast of Oregon and Washington than was revealed in either of the other two composites. The heavy rainfall events were also typically associated with an atmospheric river with anomalously high precipitable water (PW) and 850-hPa moisture flux (MF) within it. The standardized PW and MF anomalies associated with the heavy grouping were higher and were slower moving than in either of the lighter bins.
Three multiday heavy rainfall events were closely examined in order to ascertain whether anomaly patterns could provide forecast utility. Each of the multiday extreme rainfall events investigated was associated with atmospheric rivers that contained highly anomalous 850-hPa MF and PW within it. Each case was also associated with an unusually intense negative geopotential height anomaly that was similarly located off of the west coast of the United States. The similarities in the anomaly pattern among the three multiday extreme events suggest that standardized anomalies might be useful in predicting extreme multiday rainfall events in the northern Sierra range.
The Impact of Variational Assimilation of SSM/I and QuikSCAT Satellite Observations on the Numerical Simulation of Indian Ocean Tropical Cyclones
Authors: Singh Randhir , Pal P. K. , Kishtawal C. M. , Joshi P. C. 
Published: June 2008

Abstract
In this study, the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) with three-dimensional variational data assimilation (3DVAR) is utilized to investigate the influence of Special Sensor Microwave Imager (SSM/I) and Quick Scatterometer (QuikSCAT) observations on the prediction of an Indian Ocean tropical cyclone. The 3DVAR sensitivity runs were conducted separately with QuikSCAT wind vectors, SSM/I wind speeds, and total precipitable water (TPW) to investigate their individual impact on cyclone intensity and track. The Orissa supercyclone over the Bay of Bengal during October 1999 was used for simulation and assimilation experiments.
Assimilation of the QuikSCAT wind vector improves the initial position of the cyclone’s center with a position error of 33 km, which was 163 km in the background analysis. Incorporation of QuikSCAT winds was found to increase the air–sea heat fluxes over the cyclonic region, which resulted in the improved simulated intensity when compared with the simulation made without QuikSCAT winds in the initial conditions. The cyclone track improved significantly with assimilation of QuikSCAT wind vectors. The track improvement resulted from relocation of the initial cyclonic vortex after assimilation of QuikSCAT wind vectors.
Like QuikSCAT, assimilation of SSM/I wind speeds strengthened the cyclonic circulation in the initial conditions. This increase in the low-level wind speeds enhanced the air–sea exchange processes and improved the simulated intensity of the cyclone. The lack of information about the wind direction from SSM/I prevented it from making much of an impact on track prediction. As compared to the first guess, assimilation of the SSM/I TPW shows a moistening of the lower troposphere over most of the Bay of Bengal except over the central region of the cyclone, where the assimilation of SSM/I TPW reduces the lower-tropospheric moisture. This decrease of moisture in the TPW assimilation experiment resulted in a weak cyclone intensity.
Investigating the Utility of Using Cross-Oceanic Training Sets for Superensemble Forecasting of Eastern Pacific Tropical Cyclone Track and Intensity
Authors: Jordan Mark R. , Krishnamurti T. N. , Clayson Carol Anne 
Published: June 2008

Abstract
This paper examines how combining training-set forecasts from two separate oceanic basins affects the resulting tropical cyclone track and intensity forecasts in a particular oceanic basin. Atlantic and eastern Pacific training sets for 2002 and 2003 are combined and used to forecast 2004 eastern Pacific tropical cyclones in a real-time setting. These experiments show that the addition of Atlantic training improves the 2004 eastern Pacific forecasts. Finally, a detailed study of training-set and real-time model biases is completed in an effort to determine why cross-oceanic training may have helped in this instance.
Lower-Tropospheric Enhancement of Gravity Wave Drag in a Global Spectral Atmospheric Forecast Model
Authors: Hong Song-You , Choi Jung , Chang Eun-Chul , Park Hoon , Kim Young-Joon 
Published: June 2008

Abstract
The impacts of enhanced lower-tropospheric gravity wave drag induced by subgrid-scale orography on short- and medium-range forecasts as well as seasonal simulations are examined. This study reports on the enhanced performance of the scheme proposed by Kim and Arakawa, which has been used in the National Centers for Environmental Prediction (NCEP) Global Spectral Model since 1997. The performance is evaluated against a traditional upper-level drag scheme that is also available in the model. The experiment results reveal that the Kim–Arakawa scheme improves the movement and intensity of an extratropical cyclone and a continental high pressure system that was accompanied by heavy snowfall over Korea on 14–15 February 2001. The monthly verification for medium-range forecasts in December 2006, which are initialized by the NCEP operational analysis, demonstrates overall improvements in the forecasts of large-scale fields in the Northern Hemisphere. Moderate improvements are also found in the seasonal simulation of December–February for the years 1996/97, 1997/98, and 1999/2000. This study concludes that the enhanced lower-level drag should be properly parameterized in global atmospheric models for numerical weather prediction and seasonal prediction.
Developments in Operational Long-Range Climate Prediction at CPC
Authors: O’Lenic Edward A. , Unger David A. , Halpert Michael S. , Pelman Kenneth S. 
Published: June 2008

Abstract
The science, production methods, and format of long-range forecasts (LRFs) at the Climate Prediction Center (CPC), a part of the National Weather Service’s (NWS’s) National Centers for Environmental Prediction (NCEP), have evolved greatly since the inception of 1-month mean forecasts in 1946 and 3-month mean forecasts in 1982. Early forecasts used a subjective blending of persistence and linear regression-based forecast tools, and a categorical map format. The current forecast system uses an increasingly objective technique to combine a variety of statistical and dynamical models, which incorporate the impacts of El Niño–Southern Oscillation (ENSO) and other sources of interannual variability, and trend. CPC’s operational LRFs are produced each midmonth with a “lead” (i.e., amount of time between the release of a forecast and the start of the valid period) of ½ month for the 1-month outlook, and with leads ranging from ½ month through 12½ months for the 3-month outlook. The 1-month outlook is also updated at the end of each month with a lead of zero. Graphical renderings of the forecasts made available to users range from a simple display of the probability of the most likely tercile to a detailed portrayal of the entire probability distribution.
Efforts are under way at CPC to objectively weight, bias correct, and combine the information from many different LRF prediction tools into a single tool, called the consolidation (CON). CON ½-month lead 3-month temperature (precipitation) hindcasts over 1995–2005 were 18% (195%) better, as measured by the Heidke skill score for nonequal chances forecasts, than real-time official (OFF) forecasts during that period. CON was implemented into LRF operations in 2006, and promises to transfer these improvements to the official LRF.
Improvements in the science and production methods of LRFs are increasingly being driven by users, who are finding an increasing number of applications, and demanding improved access to forecast information. From the forecast-producer side, hope for improvement in this area lies in greater dialogue with users, and development of products emphasizing user access, input, and feedback, including direct access to 5 km × 5 km gridded outlook data through NWS’s new National Digital Forecast Database (NDFD).
Dryline Characteristics near Lubbock, Texas, Based on Radar and West Texas Mesonet Data for May 2005 and May 2006
Authors: Geerts Bart 
Published: June 2008

Abstract
Two months of Lubbock, Texas, radar reflectivity data and West Texas Mesonet data are examined to detect dryline finelines and to describe their thermodynamic and propagation characteristics. Before sunset the moist air mass east of the dryline was consistently denser than the dry air mass. This air density difference waned and even reversed after sunset, because of more rapid cooling on the dry side.
This study provides further evidence that the formation and propagation of the dryline convergence zone is driven by the daytime air density difference, that is, that the dryline behaves as a density current. The implication for forecasters is that the air density (or virtual potential temperature) difference across the dryline should be monitored, as a measure of dryline strength and as an additional indicator for the likelihood of convective initiation along the dryline.
Wind–Evaporation Feedback and the Axisymmetric Transition to Angular Momentum–Conserving Hadley Flow
Authors: Boos William R. , Emanuel Kerry A. 
Published: June 2008

Abstract
The effect of wind-induced surface heat exchange (WISHE) on axisymmetric, solstitial Hadley circulations is examined for forcings strong enough to produce meridional flow that nearly conserves absolute angular momentum in the free troposphere. Such forcings are known to produce an off-equatorial ascent zone in the summer hemisphere where the convergence of zonal momentum is balanced by drag on surface westerlies. Here, a convective quasi-equilibrium model with two vertical modes is used to show that enhanced surface entropy fluxes induced by these westerlies can intensify and shift both this ascent zone and the subcloud-layer entropy peak toward the equator. The equatorward shift of the subcloud entropy peak is associated with a reduction in the forcing amplitude needed to produce angular momentum–conserving (AMC) meridional flow. A previous theory of frontogenesis in tropical cyclones is adapted to axisymmetric Hadley circulations to show how WISHE shifts the peak subcloud entropy toward the equator.
These effects also occur for forcings that vary in a seasonal cycle, with the precise effect of WISHE depending on the peak amplitude of the forcing. For weak seasonally varying forcings, WISHE can abruptly increase the intensity of a local, viscous circulation, whereas for forcings of intermediate strength WISHE produces a transition to AMC flow when such a transition would not otherwise occur. For the strongest forcings, WISHE shifts the transition to AMC flow to a time earlier in the seasonal cycle. The possible relevance of these results to monsoon dynamics is discussed, as are possible effects of processes not represented in these axisymmetric models.
Influence of South Atlantic Sea Surface Temperatures on Rainfall Variability and Extremes over Southern Africa
Authors: Williams C. J. R. , Kniveton D. R. , Layberry R. 
Published: June 2008

AbstractIt is generally agreed that changing climate variability, and the associated change in climate extremes, may have a greater impact on environmentally vulnerable regions than a changing mean. This research investigates rainfall variability, rainfall extremes, and their associations with atmospheric and oceanic circulations over southern Africa, a region that is considered particularly vulnerable to extreme events because of numerous environmental, social, and economic pressures. Because rainfall variability is a function of scale, high-resolution data are needed to identify extreme events. Thus, this research uses remotely sensed rainfall data and climate model experiments at high spatial and temporal resolution, with the overall aim being to investigate the ways in which sea surface temperature (SST) anomalies influence rainfall extremes over southern Africa.Extreme rainfall identification is achieved by the high-resolution microwave/infrared rainfall algorithm dataset. This comprises satellite-derived daily rainfall from 1993 to 2002 and covers southern Africa at a spatial resolution of 0.1° latitude–longitude. Extremes are extracted and used with reanalysis data to study possible circulation anomalies associated with extreme rainfall. Anomalously cold SSTs in the central South Atlantic and warm SSTs off the coast of southwestern Africa seem to be statistically related to rainfall extremes. Further, through a number of idealized climate model experiments, it would appear that both decreasing SSTs in the central South Atlantic and increasing SSTs off the coast of southwestern Africa lead to a demonstrable increase in daily rainfall and rainfall extremes over southern Africa, via local effects such as increased convection and remote effects such as an adjustment of the Walker-type circulation.
Pacific Decadal Variability in the View of Linear Equatorial Wave Theory*
Authors: Emile-Geay Julien , Cane Mark A. 
Published: June 2008

Abstract
It has recently been proposed, within the framework of the linear shallow-water equations, that tropical Pacific decadal variability (PDV) can be accounted for by basin modes with eigenperiods of 10 to 20 yr, amplifying a midlatitude wind forcing with an essentially white spectrum. Here the authors use a different formalism of linear equatorial wave theory. The Green’s function is computed for the wind-forced response of a linear equatorial shallow-water ocean and use the earlier results of Cane and Moore to obtain a compact, closed form expression for the motion of the equatorial thermocline, which applies to all frequencies lower than seasonal. This expression is new and allows a systematic comparison of the effect of low- and high-latitude winds on the equatorial thermocline. At very low frequencies (decadal time scales), the planetary geostrophic solution used by Cessi and Louazel is recovered, as well as the equatorial wave solution of Liu, and a formal explanation for this convergence is given. Nonetheless, this more general solution leads one to a different interpretation of the results. In contrast to the aforementioned studies, the authors find that the equatorial thermocline is inherently more sensitive to local than to remote wind forcing and that planetary Rossby modes only weakly alter the spectral characteristics of the response. Tropical winds are able to generate a strong equatorial response with periods of 10 to 20 yr, while midlatitude winds can only do so for periods longer than about 50 yr. The results suggest that ocean basin modes are an unlikely explanation of decadal fluctuations in tropical Pacific sea surface temperature.