The use of numerical weather prediction (NWP) has brought significant improvements to severe weather outbreak forecasting; however, determination of the primary mode of severe weather (in particular tornadic and nontornadic outbreaks) continues to be a challenge. Uncertainty in model runs contributes to forecasting difficulty; therefore it is beneficial to a forecaster to understand the sources and magnitude of uncertainty in a severe weather forecast. This research examines the impact of data assimilation, microphysics parameterizations, and planetary boundary layer (PBL) physics parameterizations on severe weather forecast accuracy and model variability, both at a mesoscale and synoptic-scale level. NWP model simulations of twenty United States tornadic and twenty nontornadic outbreaks are generated. In the first research phase, each case is modeled with three different modes of data assimilation and a control. In the second phase, each event is modeled with 15 combinations of physics parameterizations: five microphysics and three PBL, all of which were designed to perform well in convective weather situations. A learning machine technique known as a support vector machine (SVM) is used to predict outbreak mode for each run for both the data assimilated model simulations and the different parameterization simulations. Parameters determined to be significant for outbreak discrimination are extracted from the model simulations and input to the SVM, which issues a diagnosis of outbreak type (tornadic or nontornadic) for each model run. In the third phase, standard synoptic parameters are extracted from the model simulations and a k-means cluster analysis is performed on tornadic and nontornadic outbreak data sets to generate synoptically distinct clusters representing atmospheric conditions found in each type of outbreak. Variations among the synoptic features in each cluster are examined across the varied physics parameterization and data assimilation runs. Phase I found that conventional and HIRS-4 radiance assimilation performs best of all examined assimilation variations by lowering false alarm ratios relative to other runs. Phase II found that the selection of PBL physics produces greater spread in the SVM classification ability. Phase III found that data assimilation generates greater model changes in the strength of synoptic-scale features than either microphysics or PBL physics parameterization.

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<p dir="ltr">It is known that tornadic storms favor environments characteristic of high values of thermal instability, adequate vertical wind shear, abundant near-surface moisture supply, and strong storm-relative helicity at the lowest 1-km boundary layer. These mesoscale environmental conditions and associated storm behaviors are strongly governed by large-scale synoptic patterns and sensitive to variabilities in near-surface characteristics, which are less known in the current research community. This study aims to advance the relatively underexplored area regarding the interaction between surface characteristics, mesoscale environmental conditions, and large-scale synoptic patterns driving tornadic storms in the U.S. </p><p dir="ltr">We first investigate the impact of surface drag on the structure and evolution of these boundaries, their associated distribution of near-surface vorticity, and tornadogenesis and maintenance. Comparisons between idealized simulations without and with drag introduced in the mature stage of the storm prior to tornadogenesis reveal that the inclusion of surface drag substantially alters the low-level structure, particularly with respect to the number, location, and intensity of surface convergence boundaries. Substantial drag-generated horizontal vorticity induces rotor structures near the surface associated with the convergence boundaries in both the forward and rear flanks of the storm. Stretching of horizontal vorticity and subsequent tilting into the vertical along the convergence boundaries lead to elongated positive vertical vorticity sheets on the ascending branch of the rotors and the opposite on the descending branch. The larger near-surface pressure deficit associated with the faster development of the near-surface cyclone when drag is active creates a downward dynamic vertical pressure gradient force that suppresses vertical growth, leading to a weaker and wider tornado detached from the surrounding convergence boundaries. A conceptual model of the low-level structure of the tornadic supercell is presented that focuses on the contribution of surface drag, with the aim of adding more insight and complexity to previous conceptual models.</p><p dir="ltr">We then examine the behaviors and dynamics of TLVs in response to a range of surface drag strengths in idealized simulations and explore their sensitivities to different storm environments. We find that the contribution of surface drag on TLV development is strongly governed by the interaction between surface rotation, surface convergence boundaries, and the low-level mesocyclone. Surface drag facilitates TLV formation by enhancing near-surface vortices and low-level lifting, mitigating the need for an intense updraft gradient developing close to the ground. As surface drag increases, a wider circulation near the surface blocks the inflow from directly reaching the rotating core, leading to a less tilted structure that allows the TLV position beneath the pressure minima aloft. Further increase in drag strength discourages TLV intensification by suppressing vertical stretching due to a negative vertical pressure perturbation gradient force, and it stops benefiting from the support of surrounding convergence boundaries and the overlying low-level updraft, instead becoming detached from them. We hence propose a favorable condition for TLV formation and duration where a TLV forms a less tilted structure directly beneath the low-level mesocyclone but also evolves near surrounding surface boundaries, which scenario strongly depends on underlying surface drag strength. </p><p dir="ltr">Beyond near-surface characteristics, we further explore how these storm-favorable environmental conditions may interact with the larger-scale synoptic patterns and how these interactions may affect the tornadic storm potential in the current warming climate. We employ hierarchical clustering analysis to classify the leading synoptic patterns driving tornadic storms across different geographic regions in the U.S. We find that the primary synoptic patterns are distinguishable across geographic regions and seasonalities. The intense upper-level jet streak described by the high values of eddy kinetic energy (EKE) associated with the dense distribution of Z500 contours dominates the tornado events in the southeast U.S. in the cold season (November-March). Late Spring and early Summer Tornado events in the central and south Great Plains are dominated by deep trough systems to the west axes of the tornado genesis position, while more summer events associated with weak synoptic forcing are positioned closer to the lee side of Rocky Mountain. Moreover, the increasing trend in tornado frequency in the southeastern U.S. is mainly driven by synoptic patterns with intense forcing, and the decreasing trends in portions of the Great Plains are associated with weak synoptic forcing. This finding indicates that the physical mechanisms driving the spatial trends of tornado occurrences differ across regions in the U.S.</p>

Evangelicals have been characterized as a people committed to the Bible with historical roots to the fundamentalists who were engaged in controversy with liberals in North America at the beginning of the twentieth century. Harold Lindsell's book, The Battle For The Bible (1976), led to a great deal of discussion about inerrancy among evangelicals which resulted in major conferences and the publication of a number of books and articles discussing inerrancy in the subsequent decade. The principal doctrinal statement of the Evangelical Theological Society (ETS) has been from its inception a statement on inerrancy. The inerrancy debate among evangelicals took a new direction with the publication of R H Gundry's commentary on Matthew (1982). This sparked a debate concerning redaction criticism and the compatibility of using the historical-critical methodology while maintaining a commitment to the doctrine of inerrancy. Just when the debate appeared to be dying down the publication of the results of the Jesus Seminar (1993) led to several responses from evangelicals. The most controversial publication was The Jesus Crisis (1998) which accused evangelicals and some within the ETS of embracing the same methodology as those of the Jesus Seminar, refueling the debate again. Consequently this debate amongst evangelicals, particularly those associated with the ETS has continued for almost two decades. The debate has ranged over a variety of issues related to historical criticism and the study of the Gospels, including presuppositions, the Synoptic Problem, the role of harmonization, and whether the Gospels provide a strict chronology of the life of Jesus. The role of form and tradition criticism and the criteria of authenticity and whether the Gospel writers were faithful historians or creative theologians have also been points of contention in the debate. The languages that Jesus spoke and whether the Gospels preserve the ipsissima verba or vox have highlighted the differing views about the requirements of inerrancy. The redaction criticism debate has proven to have a significant role in exposing differences in methodology, definitions, presuppositions, and boundaries among evangelicals and members of the ETS. / New Testament / D.Th. (New Testament)

Evangelicals have been characterized as a people committed to the Bible with historical roots to the fundamentalists who were engaged in controversy with liberals in North America at the beginning of the twentieth century. Harold Lindsell's book, The Battle For The Bible (1976), led to a great deal of discussion about inerrancy among evangelicals which resulted in major conferences and the publication of a number of books and articles discussing inerrancy in the subsequent decade. The principal doctrinal statement of the Evangelical Theological Society (ETS) has been from its inception a statement on inerrancy. The inerrancy debate among evangelicals took a new direction with the publication of R H Gundry's commentary on Matthew (1982). This sparked a debate concerning redaction criticism and the compatibility of using the historical-critical methodology while maintaining a commitment to the doctrine of inerrancy. Just when the debate appeared to be dying down the publication of the results of the Jesus Seminar (1993) led to several responses from evangelicals. The most controversial publication was The Jesus Crisis (1998) which accused evangelicals and some within the ETS of embracing the same methodology as those of the Jesus Seminar, refueling the debate again. Consequently this debate amongst evangelicals, particularly those associated with the ETS has continued for almost two decades. The debate has ranged over a variety of issues related to historical criticism and the study of the Gospels, including presuppositions, the Synoptic Problem, the role of harmonization, and whether the Gospels provide a strict chronology of the life of Jesus. The role of form and tradition criticism and the criteria of authenticity and whether the Gospel writers were faithful historians or creative theologians have also been points of contention in the debate. The languages that Jesus spoke and whether the Gospels preserve the ipsissima verba or vox have highlighted the differing views about the requirements of inerrancy. The redaction criticism debate has proven to have a significant role in exposing differences in methodology, definitions, presuppositions, and boundaries among evangelicals and members of the ETS. / New Testament / D.Th. (New Testament)

Anyone familiar with the Rastafari movement and its connection with the Bible is struck by the prevalence of I-locution found in them both. Because the phenomenon is important in the canonical Testaments, more so the New, this study seeks to investigate its significance in certain epistolary pieces (Romans 7 :14-25 ; 15 :14-33), the bio-Narratives and the Apocalypse, in their historical and cultural milieu. The next stage of the investigation then compares the findings of the aforementioned New Testament books with corresponding statements of the Rasta community to determine their relevance for the ongoing Anglophone theological discussion. In this connection, the following questions are addressed: (1) what are the inter-textual link(s) and function(s) of the `I' statements in Romans? (2) How do they relate to similar dominical sayings? And (3) can any parallel be established between the language of Rastafari and these? In sum, the study seeks to bring into critical dialogue the permutative `I' of the NT with the self-understanding of Rastafari. / NEW TESTAMENT / DTH (NEW TESTAMENT)

Approved for public release; distribution in unlimited. / On day five of combat operations during Operation IRAQI FREEDOM, advances by coalition forces were nearly halted by a dust storm, initiated by the passage of a synoptically driven cold front. This storm impacted ground and air operations across the entire Area of Responsibility, and delayed an impending ground attack on the Iraqi capital. Military meteorologists were able to assist military planners in mitigating at least some of the effects of this storm. This thesis examines the synoptic conditions leading to the severe dust storm, evaluates the numerical weather prediction model performance in predicting the event, and reviews metrics pertaining to the overall impacts on the Operation IRAQI FREEDOM combined air campaign. In general, the numerical model guidance correctly predicted the location and onset of the dust storms on 25 March, 2003. As a result of this forecast guidance, mission planners were able to front load Air Tasking Orders with extra sorties prior to the onset of the dust storm, and were able to make changes to planned weapons loads, favoring GPS-guided munitions. / Captain, United States Air Force