scholarly journals AN ANALYSIS OF RAINFALL EXTREMES IN THE NORTHERN SOUTH AMERICA AND THEIR BEHAVIORS FOR FUTURE CLIMATE BASED ON A1B SCENARIO

Author(s):  
Paula Fonseca ◽  
José Augusto Veiga ◽  
Francis Correia ◽  
Chou Chan ◽  
André Lyra
2020 ◽  
Vol 749 ◽  
pp. 141621 ◽  
Author(s):  
Juan F. Mendez-Espinosa ◽  
Nestor Y. Rojas ◽  
Jorge Vargas ◽  
Jorge E. Pachón ◽  
Luis C. Belalcazar ◽  
...  

2021 ◽  
pp. 875529302110275
Author(s):  
Carlos A Arteta ◽  
Cesar A Pajaro ◽  
Vicente Mercado ◽  
Julián Montejo ◽  
Mónica Arcila ◽  
...  

Subduction ground motions in northern South America are about a factor of 2 smaller than the ground motions for similar events in other regions. Nevertheless, historical and recent large-interface and intermediate-depth slab earthquakes of moment magnitudes Mw = 7.8 (Ecuador, 2016) and 7.2 (Colombia, 2012) evidenced the vast potential damage that vulnerable populations close to earthquake epicenters could experience. This article proposes a new empirical ground-motion prediction model for subduction events in northern South America, a regionalization of the global AG2020 ground-motion prediction equations. An updated ground-motion database curated by the Colombian Geological Survey is employed. It comprises recordings from earthquakes associated with the subduction of the Nazca plate gathered by the National Strong Motion Network in Colombia and by the Institute of Geophysics at Escuela Politécnica Nacional in Ecuador. The regional terms of our model are estimated with 539 records from 60 subduction events in Colombia and Ecuador with epicenters in the range of −0.6° to 7.6°N and 75.5° to 79.6°W, with Mw≥4.5, hypocentral depth range of 4 ≤  Zhypo ≤ 210 km, for distances up to 350 km. The model includes forearc and backarc terms to account for larger attenuation at backarc sites for slab events and site categorization based on natural period. The proposed model corrects the median AG2020 global model to better account for the larger attenuation of local ground motions and includes a partially non-ergodic variance model.


The Condor ◽  
2021 ◽  
Author(s):  
Natália Stefanini Da Silveira ◽  
Maurício Humberto Vancine ◽  
Alex E Jahn ◽  
Marco Aurélio Pizo ◽  
Thadeu Sobral-Souza

Abstract Bird migration patterns are changing worldwide due to current global climate changes. Addressing the effects of such changes on the migration of birds in South America is particularly challenging because the details about how birds migrate within the Neotropics are generally not well understood. Here, we aim to infer the potential effects of future climate change on breeding and wintering areas of birds that migrate within South America by estimating the size and elevations of their future breeding and wintering areas. We used occurrence data from species distribution databases (VertNet and GBIF), published studies, and eBird for 3 thrush species (Turdidae; Turdus nigriceps, T. subalaris, and T. flavipes) that breed and winter in different regions of South America and built ecological niche models using ensemble forecasting approaches to infer current and future potential distributions throughout the breeding and wintering periods of each species. Our findings point to future shifts in wintering and breeding areas, mainly through elevational and longitudinal changes. Future breeding areas for T. nigriceps, which migrates along the Andes Mountains, will be displaced to the west, while breeding displacements to the east are expected for the other 2 species. An overall loss in the size of future wintering areas was also supported for 2 of the species, especially for T. subalaris, but an increase is anticipated for T. flavipes. Our results suggest that future climate change in South America will require that species shift their breeding and wintering areas to higher elevations in addition to changes in their latitudes and longitude. Our findings are the first to show how future climate change may affect migratory birds in South America throughout the year and suggest that even closely related migratory birds in South America will be affected in different ways, depending on the regions where they breed and overwinter.


1940 ◽  
Vol 18d (5) ◽  
pp. 173-190 ◽  
Author(s):  
Henry J. Griffiths

A morphological and biological study is presented of a hitherto unrecorded member of the genus Strongyloides from the golden-rumped agouti (Dasyprocta agouti), a rodent native to Trinidad, B.W.I., and northern South America. The name Strongyloides agoutii sp. nov. is proposed for this species.Observations on the free-living development over a period of three years showed the indirect type to prevail; no seasonal variation was observed. Continuous propagation of the free-living generation of this species was not observed in faecal cultures or on artificial media.A brief résumé of the classical studies on species of the genus Strongyloides is included, together with a summary of existing hypotheses and theories on the biology of this group. A list of species and hosts for this genus is given.


2017 ◽  
Vol 51 (5-6) ◽  
pp. 1901-1914 ◽  
Author(s):  
Armineh Barkhordarian ◽  
Hans von Storch ◽  
Eduardo Zorita ◽  
Paul C. Loikith ◽  
Carlos R. Mechoso

1944 ◽  
Vol 34 (4) ◽  
pp. 101 ◽  
Author(s):  
Oscar Haught

Phytotaxa ◽  
2013 ◽  
Vol 93 (1) ◽  
pp. 25 ◽  
Author(s):  
TEUVO AHTI ◽  
HARRIE J. M. SIPMAN

The diversity of the lichen family Cladoniaceae in the Neotropics is apparently underestimated. A revision of the family for the Flora of the Guianas resulted in the description of 10 species new to science from Northern South America: Cladonia cayennensis; Cladonia flavocrispata; Cladonia isidiifera; Cladonia maasii; Cladonia mollis; Cladonia persphacelata; Cladonia recta; Cladonia rupununii; Cladonia subsphacelata; Cladonia termitarum.


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