Search results for "cyclone"
showing 10 items of 114 documents
Long-term impacts of tropical storms and earthquakes on human population growth in Haiti and Dominican Republic
2010
AbstractThe two Caribbean states, Haiti and the Dominican Republic, have experienced similar natural forces since the 18th century, including hurricanes and earthquakes. Although, both countries seem to be two of the most prone of all Latin American and Caribbean countries to natural hazard events, historically, Haiti tends to be more vulnerable to natural forces. The purpose of this article is to understand to what extent geohazards shape demographic changes. Research findings of this study show that neither atmospheric nor seismic hazards that directly hit the territory of Haiti have significant impacts on population densities and growth rates. Quantitative evidence is provided, that betw…
Sharpness of the extratropical tropopause in baroclinic life cycle experiments
2007
[1] The sharpness of the extratropical tropopause is investigated using baroclinic life cycle experiments. In these simulations, slow synoptic scale dynamics leads to a net tropopause sharpening. The mechanism involves vertical convergence of the ageostrophic wind. The results support earlier suggestions from idealized theoretical studies.
Winter “weekend effect” in southern Europe and its connections with periodicities in atmospheric dynamics
2008
[1] Winter weekly cycles of different climatic variables have been detected over Spain during the 1961–2004 period. The 13 analyzed series come from stations placed on different climatological and geographical areas with different level of urban influence. Therefore, the weekly cycles can hardly be related with local effects. Contrarily, we suggest that the weekly cycles may be related with changes in the atmospheric circulation over Western Europe, which may be due to some indirect effect of anthropogenic aerosols. Particularly interesting is the observed increase in Sea Level Pressure over Southern Europe during the weekends and consequently a decrease of anticyclonic conditions during th…
Werewolves and warning signs: Cultural responses to tropical cyclones in Mauritius
2022
The role that culture plays in the way different groups experience, respond to, and recover from disasters has been widely discussed. Yet, while there is a considerable (and growing) literature of case study evidence for the need to account for culture in disasters, comparatively few studies take a long-term perspective on cultural interactions with disasters, resulting in a lack of exploration into the diachronic nature of these cultural responses, both past and present. The literature that does exist tends also to focus either on western cultures or on groups that pursue highly traditional livelihoods. Communities that call on elements of both local or vernacular knowledge and scientific …
Improving Separation of Oil and Water Using a Novel Coalescing Centrifugal Pump
2017
Abstract A novel centrifugal pump, which increases oil droplet sizes in produced water, has been developed. This paper investigates a concept of pumping pressure optimization with respect to downstream separation efficiency, for the new pump. The investigation shows that the coalescing centrifugal pump always increases the separation efficiency of a downstream hydrocyclone. Furthermore, it is seen that the pumping pressure can be adjusted to maximize the improvement. Experimental results demonstrate how pumping conditions, which minimize the volume fraction of droplets with a diameter smaller than the cut size of the hydrocyclone, maximize the separation efficiency. Finally, it is exemplifi…
Variable Step Size P&O Algorithms for Coalescing Pump/Deoiling Hydrocyclone Produced Water Treatment System
2020
This paper presents three variable step size P&O algorithms for optimizing the separation efficiency of a coalescing pump/deoiling hydrocyclone produced water treatment system. By continuously adjusting the pumping pressure, and subsequently the coalescing effect, the algorithms are used to minimize the oil concentration downstream the hydrocyclone. Due to the variable step size, the algorithms react rapidly to changes in the upstream produced water characteristics, at the same time as they reduce (or eliminate) steady-state oscillations. Based on both simulation and experimental testing, the study discusses advantages and disadvantages of the algorithms.
A Tropical Archipelago
2017
The tropical maritime climate of the Philippines is marked by high temperature and abundant rainfall. The chapter first examines the major characteristics of the climate, dominated by the seasonal alternation of the Amihan and Habagat monsoons, leading to sharp differences between regions for their patterns of rainy seasons. Typhoons from the western Pacific hit the islands with brutal force, even if some years are more prone than others to the onslaught of tropical storms, depending on the general atmospheric circulation and the strength—or absence—of El Nino or La Nina. Typhoons not directly hitting the Philippines can still generate high levels of rainfall and enhance flooding, due to th…
Secondary Circulation of Tropical Cyclones in Vertical Wind Shear: Lagrangian Diagnostic and Pathways of Environmental Interaction
2015
Abstract This study introduces a Lagrangian diagnostic of the secondary circulation of tropical cyclones (TCs), here defined by those trajectories that contribute to latent heat release in the region of high inertial stability of the TC core. This definition accounts for prominent asymmetries and transient flow features. Trajectories are mapped from the three-dimensional physical space to the (two dimensional) entropy–temperature space. The mass flux vector in this space subsumes the thermodynamic characteristics of the secondary circulation. The Lagrangian diagnostic is then employed to further analyze the impact of vertical wind shear on TCs in previously published idealized numerical exp…
Stratosphere–troposphere exchange (STE) in the vicinity of North Atlantic cyclones
2015
Atmospheric Chemistry and Physics, 15 (19)
Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin
2020
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