scholarly journals Late Quaternary moisture export across Central America and to Greenland: evidence for tropical rainfall variability from Costa Rican stalagmites

2009 ◽  
Vol 28 (27-28) ◽  
pp. 3348-3360 ◽  
Author(s):  
Matthew S. Lachniet ◽  
Leah Johnson ◽  
Yemane Asmerom ◽  
Stephen J. Burns ◽  
Victor Polyak ◽  
...  
Keyword(s):  
Central America ◽  
Late Quaternary ◽  
Rainfall Variability ◽  
Costa Rican ◽  
Tropical Rainfall

Elemental proxy evidence for late Quaternary palaeoenvironmental change in southern African sedimentary records: interpretation and applications

2021 ◽  
Author(s):  
M.S. Humphries
Keyword(s):  
Environmental Change ◽  
Southern Africa ◽  
Southern Oscillation ◽  
Late Quaternary ◽  
Rainfall Variability ◽  
Analytical Techniques ◽  
Summer Rainfall ◽  
Geochemical Data ◽  
Complex Nature ◽  
Cape Coast

Abstract Sediments are the most important source of Late Quaternary palaeoclimate information in southern Africa, but have been little studied from a geochemical perspective. However, recent advances in analytical techniques that allow rapid and near-continuous elemental records to be obtained from sedimentary sequences has resulted in the increasing use of elemental indicators for reconstructing climate. This paper explores the diverse information that can be acquired from the inorganic component of sediments and reviews some of the progress that has been made over the last two decades in interpreting the climatic history of southern Africa using elemental records. Despite the general scarcity of elemental records, excellent examples from the region exist, which provide some of the longest and most highly resolved sequences of environmental change currently available. Records from Tswaing crater and marine deposits on the southern KwaZulu-Natal coastline have provided rare glimpses into hydroclimate variability over the last 200 000 years, suggesting that summer rainfall in the region responded predominantly to insolation forcing on glacial-interglacial timescales. Over shorter timescales, lakes and wetlands found in the Wilderness embayment on the southern Cape coast and along the Maputaland coast in north-eastern South Africa have yielded highly-resolved elemental records of Holocene environmental change, providing insight into the changing interactions between tropical (e.g., El Niño-Southern Oscillation) and temperate (e.g., mid-latitude westerlies) climate systems affecting rainfall variability in the region. The examples discussed demonstrate the multiple environmental processes that can be inferred from elemental proxies and the unique insight this can provide in advancing our understanding of past climate change on different timescales. The interpretation of geochemical data can be complicated by the complex nature of sedimentary environments, various proxy assumptions and analytical challenges, and the reliability of sediment-based climate reconstructions is substantially enhanced through multi-proxy approaches.

Twenty-five new species of Costa Rican Limacodidae (Lepidoptera: Zygaenoidea)

Zootaxa ◽  
2004 ◽  
Vol 701 (1) ◽  
pp. 1 ◽  
Author(s):  
MARC E. EPSTEIN ◽  
JORGE F. CORRALES
Keyword(s):  
New Species ◽  
Costa Rica ◽  
South America ◽  
Central America ◽  
New Taxa ◽  
Abdominal Segment ◽  
Costa Rican ◽  
Mexican Species

Twenty-five new species of neotropical Limacodidae, primarily from Central America, are described. The majority of these species (n=15) are from Parasa and Natada generic complexes, both presently known to contain only spiny caterpillars. In the Parasa complex, they include: Parasa figueresi, new species, Parasa joanae, new species, Parasa sandrae, new species, Parasa shirleyae, new species, Euclea mesoamericana, new species, Euclea zurquicola, new species, Euclea microcippus, new species, Euclea costaricana, new species, Euclea gajentaani, new species, Euclea josepsi, new species, Talima beckeri, new species, Talima weissi, new species, and Talima erojasi, new species. In the Natada complex, two new taxa are Natada delgadoi, new species, and Natada varablancana, new species. In a generic complex with hairy caterpillars, the Phobetron complex, six new taxa are: Phobetron guzmanae, new species, Isochaetes dwagsi, new species, Isochaetes kenjii, new species, Isochaetes heevansi, new species, Isochaetes tapantiensis, new species, and Vipsophobetron davisi, new species. In the Prolimacodes and Perola complexes, caterpillars are known to be smooth. New species in the Prolimacodes complex are Prolimacodes montanus, new species, and Dichromapteryx saborioi, new species, while the Perola complex includes Perola aenea, new species, and Epiperola browni, new species. Euclea microcippus, Parasa sandrae and Vipsophobetron davisi are the smallest species known to occur in their genera. Euclea mesoamericana and Parasa figueresi are relatively common in collections but have been mistakenly grouped with Euclea cippus (Cramer) and Parasa schausi Dyar, respectively. Each was reported from both Central and South America, but is now considered to be limited to South America. Talima weissi is closely related to the Mexican species T. assimilis (Dyar), sharing both a detachable clump of hairs on 8 th abdominal segment in males and large ductus seminalis, which hold the hairs, in females. Larval descriptions or hostplants are presented for P. sandrae, P. joanae, E. mesoamericana, E. gajentaani, T. beckeri, T. weissi, I. dwagsi, I. kenjii, I. heevansi, and V. davisi. Euclea zurquicola, E. josepsi, T. erojasi, N. delgadoi, N. varablancana, P. guzmanae, I. tapantiensis, and E. browni are known from only one locality, each in Costa Rica, while the last four are known only from unique specimens.

Response of heterogeneous rainfall variability in East Asia to Hadley circulation reorganization during the late Quaternary

2020 ◽  
Vol 247 ◽  
pp. 106562
Author(s):  
Debo Zhao ◽  
Shiming Wan ◽  
Zhengyao Lu ◽  
Lina Zhai ◽  
Xuguang Feng ◽  
...  
Keyword(s):  
East Asia ◽  
Late Quaternary ◽  
Rainfall Variability ◽  
Hadley Circulation

scholarly journals Rainfall variations in central Indo-Pacific over the past 2,700 y

2019 ◽  
Vol 116 (35) ◽  
pp. 17201-17206 ◽  
Author(s):  
Liangcheng Tan ◽  
Chuan-Chou Shen ◽  
Ludvig Löwemark ◽  
Sakonvan Chawchai ◽  
R. Lawrence Edwards ◽  
...  
Keyword(s):  
Rainfall Variability ◽  
Walker Circulation ◽  
Warm Period ◽  
Tropical Rainfall ◽  
The Past ◽  
Decadal Scale ◽  
Continuous Record ◽  
Southern Central ◽  
Drying Trend ◽  
Rainfall Variations

Tropical rainfall variability is closely linked to meridional shifts of the Intertropical Convergence Zone (ITCZ) and zonal movements of the Walker circulation. The characteristics and mechanisms of tropical rainfall variations on centennial to decadal scales are, however, still unclear. Here, we reconstruct a replicated stalagmite-based 2,700-y-long, continuous record of rainfall for the deeply convective northern central Indo-Pacific (NCIP) region. Our record reveals decreasing rainfall in the NCIP over the past 2,700 y, similar to other records from the northern tropics. Notable centennial- to decadal-scale dry climate episodes occurred in both the NCIP and the southern central Indo-Pacific (SCIP) during the 20th century [Current Warm Period (CWP)] and the Medieval Warm Period (MWP), resembling enhanced El Niño-like conditions. Further, we developed a 2,000-y-long ITCZ shift index record that supports an overall southward ITCZ shift in the central Indo-Pacific and indicates southward mean ITCZ positions during the early MWP and the CWP. As a result, the drying trend since the 20th century in the northern tropics is similar to that observed during the past warm period, suggesting that a possible anthropogenic forcing of rainfall remains indistinguishable from natural variability.

scholarly journals De las representaciones de las (pos)guerras centroamericanas en la narrativa costarricense contemporánea

LETRAS ◽  
2011 ◽  
pp. 63-75
Author(s):  
Verónica Ríos Quesada
Keyword(s):  
Central America ◽  
Costa Rican ◽  
Central American ◽  
Postwar Period ◽  
American Experience ◽  
Anacristina Rossi

Las novelas Te llevaré en mis ojos de Rodolfo Arias y Limón Reggae de Anacristina Rossi representan tanto las guerras como la posguerra en Centroamérica. Inauguran un cronotopo: costarricenses en la experiencia revolucionaria centroamericana desde una mirada femenina no ligada a una subjetividad heroica. Sin embargo, en esas obras no se logra mostrar a la sociedad costarricense en el contexto transnacional, por lo que se refuerzan los cronotopos escindidos con respecto a Centroamérica que caracterizan al imaginario simbólico costarricense. The novels Te llevaré en mis ojos by Rodolfo Arias and Limón Reggae by Anacristina Rossi represent both the wars and the postwar period in Central America. They establish a chronotope: Costa Ricans in the revolutionary Central American experience from a feminine perspective which is not connected to heroic subjectivity. However, in these novels the Costa Rican context is not shown in a multinational context, thus reinforcing split chronotopes concerning Central America which characterize the Costa Rican symbolic imaginary.

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