The role of the Madden-Julian Oscillation in the El Nino and Indian drought of 2002

In 2002 India experienced a severe drought, one among the five worst droughts since records began in 1871, notable for its countrywide influence. The drought was primarily due to an unprecedented break in the monsoon during July, which persisted for almost the whole month and affected most of the sub-continent. The failure of the monsoon in 2002 was not predicted and India was not prepared for the devastating impacts on, for example, agriculture. This paper documents the evolution of the 2002 Indian summer monsoon and considers the possible factors that contributed to the drought and the failure of the forecasts. The development of the 2002/2003 El Nino and the unusually high levels of Madden-Julian Oscillation (MJO) activity during the monsoon season are identified as the central players. The 2002/2003 El Nino was characterised by very high sea-surface temperatures (SSTs) in the central Pacific that developed rapidly during the monsoon season. It is suggested that the unusual character of the developing El Nino was associated with the MJO and was a consequence of the eastward extension of the West Pacific Warm Pool, brought about primarily by a series of westerly wind events (WWEs) as part of the eastward movement of the active phase of the MJO. During the boreal summer, the MJO is usually characterised by northward movement, but in 2002 the northward component of the MJO was weak and the MJO was dominated by a strong eastward component, probably driven by the abnormally high SSTs in the central Pacific. It is suggested that a positive feedback existed between the developing El Nino and the eastward component of the MJO, which weakened the active phases of the monsoon. In particular, the unprecedented monsoon break in July could be associated with the juxtaposition of strong MJO activity with a developing El Nino, both of which interfered constructively with each other to produce major perturbations to the distribution of tropical heating. Subsequently, the main impact of the developing El Nino was a modulation of the Walker circulation that led to the overall suppression of the Indian monsoon during thess latter part of the season. It is argued that the unique combination of a rapidly developing El Nino and strong MJO activity, which was timed within the seasonal cycle to have maximum impact on the Indian summer monsoon, meant that prediction of the prolonged break in July and the seasonally deficient rainfall was a challenge for both the empirical and dynamical forecasting systems. Copyright (C) 2006 Royal Meteorological Society.

El Nino-mean state-seasonal cycle interactions in a multi-model ensemble

The modelled El Nino-mean state-seasonal cycle interactions in 23 coupled ocean-atmosphere GCMs, including the recent IPCC AR4 models, are assessed and compared to observations and theory. The models show a clear improvement over previous generations in simulating the tropical Pacific climatology. Systematic biases still include too strong mean and seasonal cycle of trade winds. El Nino amplitude is shown to be an inverse function of the mean trade winds in agreement with the observed shift of 1976 and with theoretical studies. El Nino amplitude is further shown to be an inverse function of the relative strength of the seasonal cycle. When most of the energy is within the seasonal cycle, little is left for inter-annual signals and vice versa. An interannual coupling strength (ICS) is defined and its relation with the modelled El Nino frequency is compared to that predicted by theoretical models. An assessment of the modelled El Nino in term of SST mode (S-mode) or thermocline mode (T-mode) shows that most models are locked into a S-mode and that only a few models exhibit a hybrid mode, like in observations. It is concluded that several basic El Nino-mean state-seasonal cycle relationships proposed by either theory or analysis of observations seem to be reproduced by CGCMs. This is especially true for the amplitude of El Nino and is less clear for its frequency. Most of these relationships, first established for the pre-industrial control simulations, hold for the double and quadruple CO2 stabilized scenarios. The models that exhibit the largest El Nino amplitude change in these greenhouse gas (GHG) increase scenarios are those that exhibit a mode change towards a T-mode (either from S-mode to hybrid or hybrid to T-mode). This follows the observed 1976 climate shift in the tropical Pacific, and supports the-still debated-finding of studies that associated this shift to increased GHGs. In many respects, these models are also among those that best simulate the tropical Pacific climatology (ECHAM5/MPI-OM, GFDL-CM2.0, GFDL-CM2.1, MRI-CGM2.3.2, UKMO-HadCM3). Results from this large subset of models suggest the likelihood of increased El Nino amplitude in a warmer climate, though there is considerable spread of El Nino behaviour among the models and the changes in the subsurface thermocline properties that may be important for El Nino change could not be assessed. There are no clear indications of an El Nino frequency change with increased GHG.

Multidecadal modulation of El Nino-Southern Oscillation (ENSO) variance by Atlantic Ocean sea surface temperatures

Observations suggest a possible link between the Atlantic Multidecadal Oscillation (AMO) and El Nino Southern Oscillation (ENSO) variability, with the warm AMO phase being related to weaker ENSO variability. A coupled ocean-atmosphere model is used to investigate this relationship and to elucidate mechanisms responsible for it. Anomalous sea surface temperatures (SSTs) associated with the positive AMO lead to change in the basic state in the tropical Pacific Ocean. This basic state change is associated with a deepened thermocline and reduced vertical stratification of the equatorial Pacific ocean, which in turn leads to weakened ENSO variability. We suggest a role for an atmospheric bridge that rapidly conveys the influence of the Atlantic Ocean to the tropical Pacific. The results suggest a non-local mechanism for changes in ENSO statistics and imply that anomalous Atlantic ocean SSTs can modulate both mean climate and climate variability over the Pacific.

The effect of ENSO (El Nino Southern Oscillation) on Ashes series results in Australia

An analysis of the results of those "Ashes" cricket test matches between England and Australia which are played in Australia suggests a correlation between these results and the El-Niño Southern Oscillation, or ENSO. In those years with a positive ENSO, results favour Australia, whereas in those years with a negative ENSO, results are more even. A potential mechanism is presented for this apparent correlation.

Role of the atmosphere in the seasonal phase locking of El Nino

The variations with the seasonal cycle of the atmospheric response to constant SST anomalies in the eastern tropical Pacific are investigated with the atmospheric GCM, HadAM3. The equatorial wind response is weakest in January and February when the warmest SSTs are south of the Equator and strongest in April when the warmest SSTs are on the Equator. This may have consequences for the seasonality of the onset and termination of El Niño. Westerly wind anomalies in the tropical Pacific associated with El Niño have previously been observed to shift south of the Equator, weakening on the Equator, during the northern winter. It has been suggested that this may contribute to the termination of El Niño in spring. These experiments demonstrate that such a shift can arise solely in response to the mean seasonal cycle during El Niño and does not require changes in SST anomalies.

El Nino-Southern Oscillation

This 20th anniversary edition of PAGES news explores the elusive El Niño-Southern Oscillation (ENSO) from a paleo-perspective. The initiative for this special section came out of a 2011 PMIP workshop. In a mini section, a newly introduced format in the PAGES newsletter, four articles on data assimilation address methods of combining observations and model simulations. Finally, this newsletter also features several reports on the 2013 2nd Young Scientists Meeting held in Goa, India.

The Impacts of Inter-El Nino Variability on the Tropical Atlantic and Northeast Brazil Climate

In this study, observations and numerical simulations are used to investigate how different El Nino events affect the development of SST anomalies in the Atlantic and how this relates to the Brazilian northeast (NE) precipitation. The results show that different types of El Nino have different impacts on the SST anomalies of the equatorial and tropical South Atlantic but a similar SST response in the tropical North Atlantic. Strong and long (weak and short) El Ninos with the main heating source located in the eastern (central) Pacific generate cold (warm) anomalies in the cold tongue and Benguela upwelling regions during boreal winter and spring. When the SST anomalies in the eastern equatorial and tropical South Atlantic are cold (warm), the meridional SST gradient across the equator is positive (negative) and the ITCZ is not allowed (allowed) to move southward during the boreal spring; as a consequence, the precipitation is below (above) the average over the NE. Thus, strong and long (weak and short) El Ninos are followed by dry (wet) conditions in the NE. During strong and long El Ninos, changes in the Walker circulation over the Atlantic and in the Pacific-South Atlantic (PSA) wave train cause easterly wind anomalies in the western equatorial Atlantic, which in turn activate the Bjerknes mechanism, establishing the cold tongue in boreal spring and summer. These easterly anomalies are also responsible for the Benguela upwelling. During short and weak El Ninos, westerly wind anomalies are present in the western equatorial Atlantic accompanied by warm anomalies in the eastern equatorial and tropical South Atlantic; a positive phase of the South Atlantic dipole develops during boreal winter. The simulations highlight the importance of ocean dynamics in establishing the correct slope of the equatorial thermocline and SST anomalies, which in turn determine the correct rainfall response over the NE.

Evidence of a genetic bottleneck in an El Nino affected population of South American fur seals, Arctocephalus australis

The South American fur seal, Arctocephalus australis, was one of the earliest otariid seals to be exploited by humans: at least 6000 years ago on the Atlantic coast and 4000 on the Pacific coast of South America. More than 750,000 fur seals were killed in Uruguay until 1991. However, a climatological phenomenon-the severe 1997-1998 El Nino Southern Oscillation (ENSO)-was responsible for the decline of 72% Of the Peruvian fur seal population due to starvation as a consequence of warming of sea-surface temperatures and primary productivity reduction. Currently, there is no precise information on global population size or on the species` conservation status. The present study includes the first bottleneck test for the Pacific and Atlantic populations of A. australis based on the analysis of seven microsatellite loci. Genetic bottleneck compromises the evolutionary potential of a population to respond to environmental changes. The perspective becomes even more alarming due to current global warming models that predict stronger and more frequent ENSO events in the future. Our analysis found moderate support for deviation from neutrality-equilibrium for the Pacific population of fur seals and none for the Atlantic population. This difference among population reflects different demographic histories, and is consistent with a greater reduction in population size in the Pacific. Such an event could be a result of the synergic effects of recurrent ENSO events and the anthropogenic impact (sealing and prey overfishing) on this population.

Un estudio de La Sombra del Viento de Carlos RuizZafón desde una perspectiva de género

Esta tesina tiene el propósito de analizar las características de algunos de lospersonajes principales de La Sombra del Viento de Carlos Ruiz Zafón desde un punto de vistade género. El estudio se basa en diferentes teorías de género que pretenden funcionar comoherramientas para poder destacar las diferencias entre las descripciones femeninas y lasmasculinas que aparecen en la obra. Primero, definimos y concretamos el término género conla ayuda de las teorías de Yvonne Hirdman. En segundo lugar, presentamos la teoría deldualismo, de acuerdo con la cual Lena Gemzöe hace una división entre las cualidadesmasculinas y femeninas. El objetivo de nuestro estudio ha sido hacer un análisis de lascaracterísticas de algunos de los personajes principales de para demostrar si existenconstrucciones de identidad de género desde una perspectiva dualista. Como resultado denuestro estudio podemos afirmar que Zafón refuerza la división entre las cualidadesmasculinas y femeninas. Los personajes masculinos son descritos como fuertes, valientes,lógicos, intelectuales e independientes. Paralelamente, las mujeres son descritas como débiles,cobardes, intuitivas y dependientes. Además, consideramos que Zafón da a todos lospersonajes masculinos mayor espacio, estatus y protagonismo en el desarrollo de la historia.En todo momento, queda claro que Zafón crea de forma inconsciente el orden de género yrefuerza as�� las diferencias sexuales.

De olho na eternidade: a construção do arquivo privado de Antonio Carlos Jobim

O arquivo de Antonio Carlos Jobim, assim como todo arquivo pessoal, foi colecionado e mantido para satisfazer o desejo de um homem que sempre se preocupou com sua imagem. Este trabalho demonstra a história da construção e organização desse acervo, além de fortalecer a hipótese de que o arquivo, em sua integridade, configura-se como uma escrita autobiográfica. Abordo a organização arquivística do fundo Antonio Carlos Jobim, dentro do Instituto que leva seu nome, e dou ênfase na subs��rie Cadernos de anotações, da s��rie Produção Intelectual do Titular. Esses cadernos s��o um tipo de documento singular, quer pelo uso que deles fazia o maestro, quer pela sua prática memorial. O estudo destas fontes primárias nos permite inferir a imagem construída pelo próprio titular, e também evidencia o plano dos guardiões dessa memória em perpetuá-la: Jobim decidiu manter um arquivo pessoal com o claro propósito de preservar sua obra e projetá-la para o futuro. Esse cuidado foi transmitido para seus herdeiros, que além das obras musicais, cuidam, hoje, de seu legado arquivístico dentro do Instituto Antonio Carlos Jobim.

Sobre a formação e o acesso a acervos de arte contemporânea: o caso do Ateliê Carlos Vergara

A institucionalização de acervos particulares de artistas não é um fenômeno recente, mas esse processo se acelerou nos últimos 30 anos. As transformações sociais decorrentes do estabelecimento de uma ordem econômica globalizada criaram novas regras no universo das organizações culturais. Este trabalho é o resultado de uma pesquisa sobre instituições respons��veis por gerir acervos de artistas contemporâneos realizada com o objetivo de encontrar diretrizes para a constituição de uma iniciativa da mesma ordem: o Ateliê Carlos Vergara. O tema foi examinado com base em entrevistas com cinco artistas plásticos brasileiros e em um levantamento sobre a trajetória de Carlos Vergara e de seu ateliê. Algumas questões relacionadas à organização e à preservação dos acervos, à sustentabilidade das instituições, ao papel dos herdeiros em sua gestão, assim como ao alinhamento dessas iniciativas aos princípios dos artistas, s��o discutidas neste texto.

A presença de Carlos Drummond de Andrade em Portugal

Este estudo pretendeu “ler” Carlos Drummond de Andrade num outro contexto cultural, procurando avaliar, através dessa “leitura”, a recepção de sua obra para além do cenário crítico-literário brasileiro. Desse modo, buscou-se novas perspectivas para a interpretação da poética de um dos autores mais representativos da poesia brasileira do s��culo XX. A intenção foi verificar como o poeta tem sido acolhido pelo público, pelos seus pares e pela crítica especializada portuguesa, bem como a atenção que tem merecido da imprensa lusitana em geral, além de procurar averiguar o espaço editorial conferido à sua obra em Portugal. Acreditando, contudo, que o exame da recepção da obra de Drummond em Portugal não deve contentar-se somente com as referências a seu nome nos discursos críticos, geralmente oriundos dos meios acadêmicos, tentou-se pensar também acerca de sua presença em outras esferas culturais, como nas obras de ficção, sobretudo as de poesia, a partir do diálogo estabelecido com alguns poetas portugueses do s��culo XX. Nesse sentido, achou-se válido analisar, por outro lado, também a presença de Portugal em Drummond, a partir dos reflexos mais vis��veis de Camões e Fernando Pessoa em sua obra.

Do café a industrialização do campo : o caso do município de S��o Carlos, em S��o Paulo

Este trabalho tem como objetivo refletir sobre o processo de desenvolvimento do capitalismo na agricultura brasileira a partir do estudo das transformações ocorridas em um município do Estado de S��o Paulo. A partir do estudo do caso do município de S��o Carlos pôde-se realizar um exercício de sistematização das informações bibliográficas e estatísticas existentes à respeito do processo de mudança da economia agrârio-exportadora de café para a etapa atual de industrialização do campo. Estudos recentes sobre a agricultura brasileira tem procurado mostrar que a industrialização do campo, ocorre a partir da década de 70,quando a industrialização no conjunto da economia brasileira já estã plenamente desenvolvida, através da chamada indústria pesada, sustentada pelo Estado e o capital monopolista internacional. A industrialização da agricultura tem sido estudada em seus vários aspectos, como a formação dos complexos agroindustriais, a intensificação das desigualdades econômicas regionais, acentuação da concentração fundiária, formação da pequena burguesia rural, proletarização crescente dos trabalhadores, expans��o do exer cito de reserva e unificação dos mercados de trabalho rural e urbano