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While conventional drought has been studied for many years, new research focuses on different aspects and types of drought. Flash Drought is a relatively new area of research in drought literature, dating back to the last ten to twenty years in the United States. Flash drought in the Caribbean has received minimal attention from researchers, but it has been studied in the United States primarily because of the 2012 flash drought event over the Great Plains. This study focuses on flash drought events in Puerto Rico and the Caribbean. Because the rapid onset and intensity of flash drought can potentially cause more devastation without established prediction methods, this research seeks to understand the synoptic scale atmospheric drivers of flash drought events. Recent occurrences of a flash drought event in this region include the 2015 event in Puerto Rico, which resulted in water rationing and shortages for residents of the island (Mote et al., 2017). The primary goal of this study is to understand how flash drought initiates and propagates for Puerto Rico and the Caribbean using two definitions of flash drought. One definition is based on soil moisture deficit, and the second definition is based on the Evaporative Demand Drought Index (EDDI), an experimental drought monitoring tool. Results suggest that an anomalous convection and positive moisture event followed by negative moisture anomalies and persistent subsidence contribute to flash drought event initiation and propagation. Additionally, large scale flash drought events seem to be initiating more frequently, suggesting that the island is becoming more susceptible to the devastations of flash drought. / Master of Science / Drought in the United States is a well-known occurrence typically caused by high temperatures and low precipitation rates. States in the Western US like California, Arizona, Nevada, and more have been negatively impacted by persistent drought. These negative impacts include water rationing laws, struggling agricultural yield, and many days without precipitation. In recent years, it has been discovered that drought has a counterpart known as flash drought. Flash drought is to flash flooding as drought is to a floodplain. Floodplains are areas prone to persistent flooding, but flash flooding occurs in a matter of minutes or hours due to extremely intense precipitation and a lack of drainage for the water to leave. Flash drought is very similar to flash flooding due to the rapid onset and intensification. Flash drought has been studied for the United States in some cases, but there is very little known about flash drought in Puerto Rico and the Caribbean. This study seeks to understand how flash drought initiates and intensifies in Puerto Rico. Results of this study suggest that flash drought can initiate immediately after a large precipitation event that is followed by days without precipitation. Because of the amount of moisture after the precipitation, the atmosphere wants to evaporate that moisture back out. As more moisture is evaporated, the land becomes drier and drier, especially when there is no follow up precipitation. The lack of follow up precipitation is also explained in this study. It was found that following the big precipitation event, the atmosphere does not create more precipitation because of a persistent state of downward vertical motion. Upward vertical motion is needed for precipitation to occur, so the combination of downward vertical motion and dry air results in a flash drought event in Puerto Rico.

Length-based stock assessment models estimating mortality rates are attractive choices for assessing fisheries with data deficiencies. The U.S. Caribbean is exploring using these models and trying to optimize their commercial sampling program for such a model. A simulation model was constructed to compare two length-based mortality estimators, the Beverton-Holt and Gedamke-Hoenig models. The simulations also tested aspects of the Gedamke-Hoenig model previously not thoroughly addressed, such as the effects of varied life history parameters, violating the assumptions of constant growth and recruitment, sample sizes (n), and sampling program length (Ys) on total mortality rate estimates (Z). Given the scenarios investigated, the Beverton-Holt model produced consistently biased, but more stable results when n was low, variation was high for both growth and recruitment, and sampling began after the change in Z took place. The Gedamke-Hoenig model was generally less biased and detected changes in Z, but produced variable results of the current Z, especially with low sample sizes and high variability. In those situations, both models can be carefully interpreted together for management advice. In the Gedamke-Hoenig model results, a clear pattern emerged in the mean accuracy and precision of the model where after an asymptote was reached, increasing n did not improve the means. The variance of the model improved with both increasing n and increasing Ys. Outliers were predictable and could be accounted for on a case-by-case basis. The model developed here can be a tool for guiding future stock assessment model choice and sample design in the U.S. Caribbean and other regions. / Master of Science

Coastal lakes, lagoons, and wetlands often provide excellent records of environmental change related to both marine and terrestrial processes. Although coastal paleoenvironments in the Caribbean have been a subject of increasing interest, long-term environmental reconstructions from lakes on the Atlantic side of the Caribbean islands are lacking. Laguna Limon is a freshwater lake in the El Seibo province of northeastern Dominican Republic. We collected a 315-cm sediment core from the center of the lake to examine lake evolution using loss-on-ignition and foraminiferal analysis. Loss-on-ignition results indicated the presence of a low-energy lagoon in the lake's present location between about 4700 and 1400 cal yr BP. During this period a foraminiferal assemblage dominated by the brackish-water Ammonia parkinsoniana but also containing relatively-abundant normal-marine salinity taxa (e.g., Quinqueloculina spp., Archaias angulatus, and Trochulina rosea) gradually was replaced by a low-diversity assemblage dominated by Ammonia tepida and Ammonia parkinsoniana, indicating a gradual decline in salinity due to the lagoon's growing isolation from the Atlantic Ocean. By 1400 cal. Yr. BP, the lake had become a shallow wetland, indicated by sediments with a high organic content. At 1200 cal. Yr. BP the lake flooded with freshwater, as it remains today. This study provides context for ongoing research into the environmental and human history of the Laguna Limon area. / Master of Science

The Caribbean and Central America region (CCAR) undergoes the entire spectrum of earthquake types due to its complex tectonic setting comprised of transform zones, young oceanic spreading ridges, and subduction along its eastern and western boundaries. CCAR is, therefore, an ideal setting in which to study the impacts of long-term tectonic deformation on the distribution of present-day seismic activity. In this work, we develop a revised continuous tectonic strain rate model based on interseismic, secular geodetic data. We compare it with its predecessor, the Global Strain Rate Model v2.1 (GSRM). Specifically, we compare predicted fault types with known active faults and evaluate the style of predicted fault types with present-day earthquake focal mechanism data. We first create a 0.25$^{circ}$ x 0.25$^{circ}$ finite element grid that is comprised of block geometries defined from previous studies. Second, we isolate and remove anomalous signals that are inconsistent with rigid block motion from the latest open access community Global Navigation Satellite System (GNSS) velocity solution from UNAVCO and combine it with GNSS data compiled for the GSRM. In a third step, we delineate zones of deformation and rigidity by creating a buffer around the boundary of each block that varies depending on the size of the block and the expected deformation zone, which are based on locations of GNSS data consistent with rigid block motion. Fourth, we assign the regions within the buffer of zero for the deforming areas and a plate index outside the buffer to constrain plate rigidity. Finally, we calculate a tectonic strain rate and continuous velocity model for CCAR using the Haines and Holt finite element approach to fit bicubic Bessel splines to the GNSS data assuming block rotation for zones of rigidity. Our model of the CCAR is consistent with compression along subduction zones, extension across the East Pacific Rise, and a combination of compression and extension across the North America - Caribbean plate boundary with a few exceptions due to limitations with the modeling approach. Modeling results are then used to calculate expected faulting behaviors that we compare with seismic activity, the GSRM, and mapped geologic faults. We find the accumulation of strain rates in areas near the Middle American Trench, Hispaniola, the northeastern Caribbean, and northern South America indicate tectonic deformation that may result in seismic events. We conclude the tectonic deformation plays a critical role in explaining present-day seismicity along land masses adjacent to the subduction zone and the Hispaniola block. / Master of Science / Central America and the Caribbean are areas with high occurrences of earthquakes. This is due to the various types of tectonic plate boundaries that occur in the region. When plates move in relation to each other, they can accumulate strain, which plays a role in the size and type of earthquakes that occur. In this work, we aim to determine the effects on strain on earthquakes. To do this, we utilize an inversion method to calculate strain rates from Global Navigation Satellite System (GNSS) data. In our model, we first create a grid of points and a geometry of the regional tectonic blocks. We then gather data from public and published sources. The model also requires that we define where the plates are allowed to deform (accumulate strain) and where they remain rigid. Using the Haines and Holt method, we invert the GNSS velocities for strain rates and velocities. We find long-term tectonic deformation dominates the present-day seismic activity in three key regions: along the Middle America Trench and across the Hispaniola block.

abstract: Las Islas Canarias son un archipiélago de la costa africana situado a cien kilómetros de la costa de Marruecos y del Sáhara Occidental. Estas islas fueron conquistadas a finales del siglo XV y son actualmente parte del Estado español, y su posición como punto de paso tricontinental ha facilitado una historia colonial que es paralela a la del Caribe y que está caracterizada por la asimilación de sus poblaciones indígenas, las plantaciones de caña de azúcar y el comercio esclavista atlántico, la emergencia de un Nuevo Mundo, las migraciones constantes desde las Islas Canarias hacia el Caribe, el desarrollo de movimientos independentistas y la turistificación del paraíso caribeño/canario, entre otros aspectos. La identidad de las Islas Canarias, si embargo, ha permanecido en una posición ambigua en la discusión de conceptos de tricontinentalidad o puente entre continentes, cuando estas islas no son simplemente consideradas como una región más de España con ligeras diferencias. Desde el Caribe, varios autores regionales han cuestionado sus propias identidades proponiendo los conceptos de creolización, relación o meta-archipiélago. Las ideas comunes exploradas por intelectuales de ambos archipiélagos incluyen los conceptos de colonialidad, modernidad, mitologización de la isla, fragmentación, atlanticidad, frontera y ultraperiferia, entre otros. De esta manera, esta tesis doctoral conecta las Islas Canarias y el Caribe a través de la exploración de sus discursos identitarios, y aplica a Canarias las teorías poscoloniales desarrolladas en el Caribe. Partiendo del análisis de diversos trabajos de Fernando Ortiz, Antonio S. Pedreira, Édouard Glissant, Jean Bernabé, Patrick Chamoiseau, Raphael Confiant, Antonio Benítez Rojo, José Luis González, Juan Flores, Gustavo Pérez-Firmat, Walter Mignolo, Enrique Dussel, Gloria Anzaldúa y Juan Manuel García Ramos, entre otros, esta tesis propone el término canaribeñidad para definir el desarrollo bilateral y común de las identidades nacionales en las Islas Canarias y el Caribe, destacando la contribución canaria a la identidad caribeña (la fundación de la literatura cubana, el guajiro/jíbaro, la brujería…) y viceversa (discursos independentistas y nacionalistas, la experiencia diaspórica, la música, el tabaco, el sentido de fraternidad con el Caribe…). El corpus analizado en esta disertación incluye obras literarias transatlánticas, desde las primeras crónicas hasta ejemplos de teatro, novelas, ensayos, artículos periodísticos y poesía de los siglos XVI-XX. / Dissertation/Thesis / Doctoral Dissertation Spanish 2019

This project explores visually experimental poetry as a particular trend in Caribbean poetry since the 1970's. Although visual experimentation in Caribbean poetry is immediately recognizable – for example, its play with font styles and sizes, its jagged margins, its division of the page into multiple discourse spaces, its use of images – little critical attention has been paid to the visual qualities of Caribbean poetry. Instead, definitions of Caribbean poetry have remained focussed upon oral/aural aesthetics, excluding its use of and contribution to late 20th century experimental poetic practice. By focussing on the poetry of Shake Keane, Claire Harris, Marlene Nourbese Philip, Kamau Brathwaite, and LeRoy Clarke, I bring post-colonial literary criticism into discussion with contemporary debates regarding visual poetic practice in North America. In so doing, this project values Caribbean visual poetry both for its expression of Caribbean cultural experience and for its contributions to broader experimental poetry movements. I argue that visual experimentation functions to disrupt traditional linear reading processes, which thereby allows poets to perform the flux of time and space in post-colonial contexts. Furthermore, such disruption of linear reading practices, often manifested by the positioning of multiple discourses on one page, serves to create a polyvocal discourse that resists patriarchal and colonialist power structures. Valuing the visual qualities of Caribbean poetry as signifying elements, this dissertation explores the aesthetic and social implications of inscription and visual design in Caribbean poetry.

<p>While great strides have been made in the study of Trinidad Carnival, there has yet to be a robust inquiry into how women have contributed to its evolution. One major reason for this shortcoming is that the dominant cultural discourse relies on a reductive</p><p>dichotomy that recognizes the costumes created prior to the 1970s as creative and those made after the 1970s as uncreative. This arbitrary division of the costume aesthetic reflects a distinct anti-feminist bias that sees women's spirited emergence in Carnival</p><p>territory in the 1970s as apolitical. </p><p>My dissertation exposes this dilemma, and seeks to undermine this</p><p>interpretation, by its focus on how women's bodies, their presentation, and their acknowledgment of the body's potential for non-verbal articulation impacted the evolution of performance practices and the costume aesthetic in Trinidad Carnival. I</p><p>explore how the predominance of women in Carnival since the 1970s and the bikinibased costume aesthetic that complements this change is suggestive of women's urgent need to manipulate the body as an aesthetic medium and site of subversion. Critical to</p><p>this argument is a close examination of certain female figures who have had a sustainable presence in Trinidad Carnival's history. My project acknowledges the <italic>jamette</italic>, a working class woman who defied Victorian tenets of decorum in preindependence</p><p>Trinidad. This figure has been overlooked in the predominant scholarship of Trinidad Carnival history. Another section of my dissertation explores the influence of the Jaycees Carnival Queen competition. Women of mostly European descent participated in this Carnival-themed beauty pageant that remained popular until the</p><p>1970s. I also examine the legend of <italic>soucouyant</italic> (an old woman who turns into a ball of fire at night and sucks the life blood from unsuspecting victims) and how this figure can be deployed to reinterpret <italic>Jouvay</italic> (the ritual that marks the beginning of Trinidad Carnival).</p> / Dissertation