scholarly journals Pacific and Atlantic Multidecadal Variability Relations with the Choco and Caribbean Low-Level Jets during the 1900–2015 Period

Atmosphere ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1120
Author(s):  
Wilmar L. Cerón ◽  
Mary T. Kayano ◽  
Rita V. Andreoli ◽  
Alvaro Avila-Diaz ◽  
Itamara Parente de Souza ◽  
...  

This study analyzes the variability of the Choco jet (CJ) and Caribbean low-level jet (CLLJ) with consideration of the simultaneous Pacific interdecadal oscillation (PDO) and Atlantic multidecadal oscillation (AMO) low-frequency mean states and their effects on the atmospheric circulation and rainfall in northwestern South America and Central America for the 1900–2015 period, during the seasons with the highest intensities of the CJ (September–November (SON)) and the CLLJ (June–August). Variations in the sea surface temperature (SST) anomaly positioning in the eastern Pacific, tropical North Atlantic (TNA)/Caribbean Sea during different mean states restrict the anomalous circulation, and, consequently, the intensity of the CJ and CLLJ. During the warm AMO (WAMO)/cold PDO (CPDO), the SST gradient from the tropical Pacific into the TNA, accompanied by a cyclonic circulation near the east coast of the Americas, intensifies the west–east circulation in the region, strengthening the CJ and weakening the CLLJ during SON such that rainfall increases over Colombia, Central America and in adjacent oceans. During the cold AMO (CAMO)/warm PDO (WPDO) phase, a relative east/west SST gradient occurs in TNA, consistent with a cyclonic circulation in western TNA, establishing an anomalous southwest–northwestward circulation from the eastern Pacific into the Caribbean basin, forming a well-configured CJ, increasing precipitation over Central America and its adjacent oceans. For the CLLJ, during CAMO phases, the anticyclonic circulations extended over most of the TNA favor its intensification from 30° W to the Caribbean Sea. In contrast, during WAMO, the cyclonic circulation near the east coast of the United States restricts its intensification to the Caribbean Sea region. To the best of our knowledge, the results presented here are new and might be useful in atmospheric modeling and extreme event studies.

2011 ◽  
Vol 24 (15) ◽  
pp. 3956-3970 ◽  
Author(s):  
Min Wen ◽  
Song Yang ◽  
Wayne Higgins ◽  
Renhe Zhang

Abstract During the boreal summer (June–August), vigorous convection appears over the eastern Pacific, southern Mexico, and northern South America, and oscillates on a distinct time scale of 10–20 days. Extended empirical orthogonal function (EEOF) analysis shows that the quasi-biweekly oscillation (QBWO) of the convection has two major modes: a west–east-orientated mode (WEM) and a north–south-orientated mode (NSM). The WEM, which is explained by the first two EEOF modes, originates over the eastern Atlantic, propagates westward along 15°N, and enhances over the Caribbean Sea before disappearing over the central Pacific. The NSM, explained by the third and fourth EEOF modes, originates over the western Pacific, moves eastward, and strengthens over the eastern Pacific. It shifts northward after arriving over the Caribbean Sea. Both modes have notable seasonal dependence, with the WEM more active in July and August and the NSM more active in June or earlier. The two distinct QBWO modes are linked to different rainfall patterns over the United States and Mexico. When the WEM is active in July and August, wet conditions occur over the southern central United States and dry conditions appear to the north. When the NSM is active in June, northern Mexico, the southwestern United States, the Missouri basin, and the northern Great Lakes are drier than normal, while southern Mexico and the eastern United States are wetter than normal. Significant variations in atmospheric circulation are found to be associated with the interannual variability of the NSM activity in June. However, these variations may not necessarily result from QBWO but, rather, provide a background for QBWO activity instead. In July and August, the association of QBWO with the precipitation pattern over North America may sometimes be related to hurricane activity.


Author(s):  
Walter D. Mignolo

This book is an extended argument about the “coloniality” of power. In a shrinking world where sharp dichotomies, such as East/West and developing/developed, blur and shift, this book points to the inadequacy of current practices in the social sciences and area studies. It explores the crucial notion of “colonial difference” in the study of the modern colonial world and traces the emergence of an epistemic shift, which the book calls “border thinking.” Further, the book expands the horizons of those debates already under way in postcolonial studies of Asia and Africa by dwelling on the genealogy of thoughts of South/Central America, the Caribbean, and Latino/as in the United States. The book's concept of “border gnosis,” or sensing and knowing by dwelling in imperial/colonial borderlands, counters the tendency of occidentalist perspectives to manage, and thus limit, understanding. A new preface discusses this book as a dialogue with Hegel's Philosophy of History.


The Condor ◽  
2001 ◽  
Vol 103 (4) ◽  
pp. 715-724 ◽  
Author(s):  
Mark S. Martell ◽  
Charles J. Henny ◽  
Peter E. Nye ◽  
Matthew J. Solensky

Abstract Satellite telemetry was used to determine fall migratory movements of Ospreys (Pandion haliaetus) breeding in the United States. Study areas were established along the lower Columbia River between Oregon and Washington; in north-central Minnesota; on Shelter Island, New York; and in southern New Jersey. Seventy-four adults (25 males, 49 females) were tracked from 1995 through 1999. Migration routes differed among populations but not by sex. Western Ospreys migrated through California and to a lesser degree other western states and wintered in Mexico (88%), El Salvador (6%), and Honduras (6%) (25.9°N to 13.0°N and 108.3°W to 87.3°W). Minnesota Ospreys migrated along three routes: (1) through the Central U.S. and then along the east coast of Mexico, (2) along the Mississippi River Valley, then across the Gulf of Mexico, or (3) through the southeastern U.S., then across the Caribbean. East Coast birds migrated along the eastern seaboard of the U.S., through Florida, and across the Caribbean. Midwestern birds wintered from Mexico south to Bolivia (22.35°N to 13.64°S, and 91.75°W to 61.76°W), while East Coast birds wintered from Florida to as far south as Brazil (27.48°N to 18.5°S and 80.4°W to 57.29°W). Dates of departure from breeding areas differed significantly between sexes and geographic regions, with females leaving earlier than males. Western birds traveled a shorter distance than either midwestern or eastern Ospreys. Females traveled farther than males from the same population, which resulted in females typically wintering south of males. Rutas de Migración Otoñales, Coordinación y Sitios de Invernada de Pandion haliaetus Determinados por Telemetría Satelital Resumen. Se utilizó telemetría satelital para determinar los movimientos de migración de otoño de individuos de Pandion haliaetus que nidifican en los Estados Unidos. Las áreas de estudio se establecieron a lo largo del Río Columbia entre Oregon y Washington; en el centro-norte de Minnesota; en la Isla Shelter, Nueva York; y en el sur de Nueva Jersey. Setenta y cuatro adultos (25 machos, 49 hembras) fueron seguidos mediante telemetría desde 1995 hasta 1999. Las rutas de migración se diferenciaron entre poblaciones pero no entre sexos. Los individuos de P. haliaetus del oeste, migraron a través de California y en menor grado a través de otros estados del oeste e invernaron en México (88%), El Salvador (6%) y Honduras (6%) (25.9°N a 13.0°N y 108.3°O a 87.3°O). Las aves de Minnesota migraron a lo largo de tres rutas: (1) a través del los E.E.U.U. centrales y luego a lo largo de la costa este de México, (2) a lo largo del valle del Río Mississippi y luego a través del Golfo de México, o (3) a través del sur de los E.E.U.U. y luego a través del Caribe. Las aves de la costa este, migraron a lo largo de la costa este de los E.E.U.U., por Florida y a través del Caribe. Las aves del medio-oeste, invernaron desde México hacia el sur hasta Bolivia (22.35°N a 13.64°S, y 91.75°O a 61.76°O), mientras que las aves de la costa este invernaron desde Florida hasta tan al sur como Brasil (27.48°N a 18.5°S y 80.4°O a 57.29°O). Las fechas de partida desde las áreas de nidificación difirieron significativamente entre sexos y regiones geográficas, partiendo las hembras antes que los machos. Las aves del oeste viajaron distancias más cortas que las aves del medio-oeste y del este. Considerando una misma población, las hembras viajaron más lejos que los machos, lo que resultó en que las hembras invernaron típicamente más al sur que los machos.


Zootaxa ◽  
2018 ◽  
Vol 4471 (2) ◽  
pp. 245 ◽  
Author(s):  
VÍCTOR M. CONDE-VELA

Pseudonereis gallapagensis Kinberg, 1865 and P. variegata (Grube & Kröyer in Grube, 1858) are the only two species of this genus commonly recorded along Atlantic American coasts, but their type localities are in the Eastern Pacific, and their morphology differs. Two new Pseudonereis species are described from Eastern Mexico: P. brunnea sp. n. from the Gulf of Mexico, and P. citrina sp. n. from the Caribbean Sea, previously confused with P. gallapagensis. In order to facilitate comparisons, descriptions based on specimens from near the type locality for P. gallapagensis (Peru and Ecuador), and topotypes for P. variegata (Valparaiso, Chile), are included. Based on these comparisons and current descriptions, the synonymies of Nereis ferox Hansen, 1882 described from Brazil with P. variegata, and of Pseudonereis formosa Kinberg, 1865 described from Hawaii with P. gallapagensis, are rejected. Consequently, both are regarded as distinct species and revised diagnoses are provided for them. The record of P. ferox from the Gulf of Guinea proved to be an undescribed species, and is herein described as P. fauveli sp. n. The number of paragnath rows in nereidid pharynx areas VII–VIII has been interpreted in several ways, leading to confusion; an alternative method to determine the number of bands and rows is proposed. The midventral region, the division of areas VII–VIII in furrow and ridge regions, and the description of the arrangement based on the pattern of paragnaths in such regions, are proposed. Further, the terms shield-shaped and pointed (P-bars) bars are redefined, and a new term, crescent-shaped bars, is proposed for paragnaths in the areas VI in some Pseudonereis and Perinereis species. A key for all Pseudonereis species is also included. 


1986 ◽  
Vol 10 (4) ◽  
pp. 467-488
Author(s):  
Donald B. Cooper

On repeated occasions in the nineteenth century, Asian cholera irrupted from its traditional center in the great river basins of India and spread in pandemic waves throughout parts of Europe, North Africa, and North America. In Spain alone 600,000 deaths resulted from cholera during four great invasions (Cárdenas, 1971: 224). The United States experienced terrifying outbreaks beginning in 1832, 1849, and 1866 (Rosenberg, 1962) which also touched parts of Mexico, Central America, and the Caribbean. Initially South America escaped the onslaught. Some Brazilians speculated that the intense heat of the equator, or the vast expanse of the Atlantic ocean, somehow offered an effective buffer to the southward spread of cholera (Rego, 1872: 84). But this “sweet illusion” was shattered in 1855. Indeed the first city in Brazil struck by Asian cholera was Belém, capital of the vast northern province of Pará located astride the equator at the mouth of the Amazon river.


1997 ◽  
Vol 75 (9) ◽  
pp. 1415-1464 ◽  
Author(s):  
Andreas Leistikow

Examination of a small collection of Oniscidea from Costa Rica revealed the presence of two species new to science (Ischioscia martinae sp.nov. and Scleropactes talamancensis sp.nov.). Further specimens from the collection of the United States National Museum were reexamined to reconsider the status of Philoscia muscorum (Scopoli, 1793) and Ischioscia variegata (Dollfus, 1893), both of which have been reported from Costa Rica. The specimens belong to two new species (Ischioscia muelleri sp.nov. and Ischioscia elongata sp.nov.). Redescriptions of Ligia baudiniana Milne Edwards, 1840 from the shores of both the Caribbean Sea and the Pacific Ocean and the type material of Ischioscia variegata (Dollfus, 1893) from Venezuela are also presented.


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