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Large-scale climate patterns affect many areas of our global environment either directly or indirectly. They provide the background conditions for regional climate patterns and weather events that in turn affect many areas of our society, such as agriculture, water supply, energy demand, and natural ecosystem development. Many scientists have analyzed how these large-scale modes of climate variability influence the climate response over North America on an individual basis, however, it is still unclear how the combination of modes of variability affect North American climate. In this study, I analyze the four leading modes of climate variability that influence North American climate patterns: the El Niño – Southern Oscillation (ENSO), the Atlantic Multidecadal Oscillation (AMO), the Pacific – North American (PNA) Pattern, and the Northern Annular Mode (NAM). Through an observational analysis, I show which climate pattern has the largest influence on a particular region of North America as well as the most common combinations of patterns to influence the continent. The oceanic patterns, ENSO and AMO, have the largest influence on the background conditions of regional climate due to their slow-varying nature, while the atmospheric patterns, PNA and NAM, have the largest influence on wintertime temperature and precipitation anomalies. The North American climate response of the combined PNA and NAM patterns is seasonally dependent, where in the boreal winter they have the largest influence when in opposition and in the summer when in the same phase. This is due in part to their common link with the Aleutian Low in the North Pacific. Furthermore, the AMO has a large influence on summer climate due to its weak seasonality and the lack of strength of the other regional climate patterns. Moreover, this study also presents an analysis on the North American climate influence of the ENSO and AMO using the NCAR CESM1 global climate model. The model results for the ENSO response are corroborated well with observations, however, the AMO response in the model is weak, which might be a result of the internal metrics of the model or a weak AMO forcing. The largest North American climate response occurs when the combined ENSO and AMO patterns are in opposition. The ENSO and AMO response is also simulated under RCP8.5 end-of-century conditions to analyze the pattern response under global warming. An eastward shift in the ENSO teleconnection occurs under future warming with the largest shift occurring under +ENSO conditions. An eastward shift occurs under –ENSO conditions only when in combination with a +AMO in the winter, suggesting the AMO having an influence on the ENSO teleconnection. Additionally, the shift in the ENSO response highlights the nonlinear nature of the ENSO teleconnection and an element of future climate change over North America.

Data integration is concerned with providing a unified access to data residing at multiple sources. Such a unified access is realized by having a global schema and a set of mappings between the global schema and the local schemas of each data source, which specify how user queries at the global schema can be translated into queries at the local schemas. Data sources are typically developed and maintained independently, and thus, highly heterogeneous. This causes difficulties in integration because of the lack of interoperability in the aspect of architecture, data format, as well as syntax and semantics of the data.This dissertation represents a study on how small, self-contained ontologies, called ontology design patterns, can be employed to provide semantic interoperability in a cross-repository data integration system. The idea of this so-called ontology pattern- based data integration is that a collection of ontology design patterns can act as the global schema that still contains sufficient semantics, but is also flexible and simple enough to be used by linked data providers. On the one side, this differs from existing ontology-based solutions, which are based on large, monolithic ontologies that provide very rich semantics, but enforce too restrictive ontological choices, hence are shunned by many data providers. On the other side, this also differs from the purely linked data based solutions, which do offer simplicity and flexibility in data publishing, but too little in terms of semantic interoperability.We demonstrate the feasibility of this idea through the actual development of a large scale data integration project involving seven ocean science data repositories from five institutions in the U.S. In addition, we make two contributions as part of this dissertation work, which also play crucial roles in the aforementioned data integration project. First, we develop a collection of more than a dozen ontology design patterns that capture the key notions in the ocean science occurring in the participating data repositories. These patterns contain axiomatization of the key notions and were developed with an intensive involvement from the domain experts. Modeling of the patterns was done in a systematic workflow to ensure modularity, reusability, and flexibility of the whole pattern collection. Second, we propose the so-called pattern views that allow data providers to publish their data in very simple intermediate schema and show that they can greatly assist data providers to publish their data without requiring a thorough understanding of the axiomatization of the patterns.

This dissertation is about the long-distance navigators who constructed a global marine world as agents of the sixteenth-century Spanish maritime empire. The hard-won pragmatic and empirical expertise on which they relied developed in an uneasy tension with the priorities of the bureaucracy centered at the Casa de la Contratación in Seville. In the Atlantic, bureaucratic standardization driven by the Casa made commercial ocean travel increasingly routine, while exploratory sailors, particularly in the Pacific, continued to apply their expertise in unknown and unpredictable waters. The quotidian and the pragmatic defined these long-distance mariners’ relationship to their environment. They organized space into networks of knowable pathways that connected places identified by names and markers that communicated the sailors’ experience to future navigators; they interpreted local conditions based on inferences from distant stimuli and ocean-scale systems; and they introduced their natural and human surroundings to metropolitan and colonial scholars and administrators. The resources and instruments developed by the Casa informed these practices, but voyages of discovery always remained outside of direct institutional control from Seville. This relationship—between the local, individual, and contingent on the one hand and the universal, bureaucratic, and synthetic on the other—not only defined the dynamics of intellectual authority governing scientific endeavors under the Spanish monarchy, but also shaped strategies for projecting imperial claims across areas of uneven and limited physical control, whether marine or terrestrial. Reevaluating the balance between marine and terrestrial territorial claims recasts the Americas as a waypoint into the Pacific and beyond for the globally-aware westward gaze of Spanish imperial ambition. More fundamentally, it highlights the multicentric and networked arrangement of power in the early modern period by refocusing our attention on those islands, whether literal or figurative, of physical Spanish presence surrounded by spaces of hypothetical control. The Spanish empire’s maritime orientation during the sixteenth century developed the intellectual, political, and institutional strategies to balance and resolve these tensions between embodied and archival knowledges, local contingencies and universal frameworks that defined the distribution of power under the Spanish monarchy.