Dengue fever epidemics in the South Pacific: driven by El Nino Southern Oscillation?

The Lancet ◽  
1996 ◽  
Vol 348 (9042) ◽  
pp. 1664-1665 ◽  
Author(s):  
S Hales ◽  
P Weinstein ◽  
A Woodward
Keyword(s):  
Dengue Fever ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
South Pacific ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
The South

scholarly journals Tropical Cyclone Climatology of the South Pacific Ocean and Its Relationship to El Niño–Southern Oscillation

2012 ◽  
Vol 25 (18) ◽  
pp. 6108-6122 ◽  
Author(s):  
Andrew J. Dowdy ◽  
Lixin Qi ◽  
David Jones ◽  
Hamish Ramsay ◽  
Robert Fawcett ◽  
...  
Keyword(s):  
Tropical Cyclone ◽  
El Niño ◽  
Large Scale ◽  
Critical Line ◽  
El Nino ◽  
Southern Oscillation ◽  
South Pacific ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
The South

Abstract Climatological features of tropical cyclones in the South Pacific Ocean have been analyzed based on a new archive for the Southern Hemisphere. A vortex tracking and statistics package is used to examine features such as climatological maps of system intensity and the change in intensity with time, average tropical cyclone system movement, and system density. An examination is presented of the spatial variability of these features, as well as changes in relation to phase changes of the El Niño–Southern Oscillation phenomenon. A critical line is defined in this study based on maps of cyclone intensity to describe the statistical geographic boundary for cyclone intensification. During El Niño events, the critical line shifts equatorward, while during La Niña events the critical line is generally displaced poleward. Regional variability in tropical cyclone activity associated with El Niño–Southern Oscillation phases is examined in relation to the variability of large-scale atmospheric or oceanic variables associated with tropical cyclone activity. Maps of the difference fields between different phases of El Niño–Southern Oscillation are examined for sea surface temperature, vertical wind shear, lower-tropospheric vorticity, and midtropospheric relative humidity. Results are also examined in relation to the South Pacific convergence zone. The common region where each of the large-scale variables showed favorable conditions for cyclogenesis coincided with the location of maximum observed cyclogenesis for El Niño events as well as for La Niña years.

scholarly journals Variabilidade da Dengue e do Clima em Porto Alegre/RS de 2012 a 2017

2019 ◽  
Vol 12 (6) ◽  
pp. 2080
Author(s):  
Erika Collischonn ◽  
Bianca Marques Maio ◽  
Ricardo Brandolt
Keyword(s):  
Dengue Fever ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
Global Climate ◽  
Meteorological Data ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Enso Cycle ◽  
Porto Alegre

O El Niño/Oscilação Sul (ENOS) é uma oscilação conjunta oceano-atmosfera, que altera a Temperatura da Superfície do Mar (TSM), a pressão, o vento e a convecção tropical, principalmente no Oceano Pacífico, porém com reflexos na circulação atmosférica e no padrão de distribuição da precipitação em outras áreas do planeta, incluindo o sul do Brasil, conforme já comprovado por vários autores. Essa alteração de padrões pode aumentar o número de pessoas expostas a doenças, como a dengue, aumentando a probabilidade de surtos ou epidemias. Neste trabalho, o recorte temporal escolhido, de 2012 a 2017, abrange os dois anos em que mais casos de dengue autóctone ocorreram em Porto Alegre (2013 e 2016). Para o período, analisaram-se variabilidades a partir dos seguintes dados: Índice Niño 3.4 (NOAA); médias e totais mensais de elementos meteorológicos e as normais climatológicas 1981-2010 de Porto Alegre (WMO 83967- INMET); casos confirmados de dengue por semana epidemiológica e ano (SINAN-RS); dias com presença de jatos de baixos níveis (JBN) sobre Porto Alegre (Projeto Rios Voadores e INPE/CPTEC). A partir da organização destes dados, foi constatada uma correspondência entre o El Niño muito forte ocorrido em 2016, a presença quase constante dos JBN sobre Porto Alegre, precipitação bem superior à normal e o maior número de casos de dengue autóctone já registrado até então. Discute-se também as diferenças e semelhanças deste ano com o de 2013, que foi o segundo ano em registros de dengue autóctone.  Variability of Climate and Dengue Fever Cases in Porto Alegre/RS from 2012 to 2017 A B S T R A C TThe El Niño / Southern Oscillation (ENSO) The El Niño-Southern Oscillation (ENSO) cycle causes ripples through the global climate, changing air currents and rainfall patterns, The effect on the climate of southern Brazil was evidenced by several authors. The shifts in Niño years can increase the number of people exposed to a disease, such as dengue, increasing the likelihood of an outbreak. In this work, we analyzed a period of time that covers the two years in which more cases of autochthonous dengue fever occurred in Porto Alegre (2013 and 2016). For this period, variability was analyzed from the following data: Niño 3.4 (NOAA), monthly mean and cumulative meteorological data and climatological normal 1981/2010 of Porto Alegre (WMO 83967- INMET); confirmed cases of dengue fever per epidemiological week and per year (SINAN-RS); days with presence of low level jets (JBN) over Porto Alegre (INPE/CPTEC). The organization of these data showed correspondence between the very strong El Niño occurred in 2016, the almost constant presence of the JBN over Porto Alegre, the most intense and frequent precipitation, and the highest number of autochthonous dengue cases ever recorded. We also discuss the differences and similarities of this year with that of 2013, which was the second year in autochthonous dengue fever records.Keywords: El Niño, Low Lever Jet, precipitation, temperature, wind, dengue fever.

Sign in / Sign up

Export Citation Format

Share Document