Combined Effects of El Niño and the Pacific Decadal Oscillation on Summertime Circulation over East Asia

2019 ◽  
Vol 55 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Sang-Heon Lee ◽  
Kyong-Hwan Seo ◽  
Minho Kwon
Keyword(s):  
East Asia ◽  
Pacific Decadal Oscillation ◽  
El Niño ◽  
El Nino ◽  
Combined Effects ◽  
The Pacific

scholarly journals Estudo da Influência da Oscilação Decadal do Pacífico no Nordeste do Brasil (Study of the Influence of Pacific Decadal Oscillation in Northeast of Brazil)

2011 ◽  
Vol 4 (4) ◽  
pp. 665 ◽  
Author(s):  
Djane Fonseca Da Silva ◽  
Josicleda Domiciano Galvíncio
Keyword(s):  
Pacific Decadal Oscillation ◽  
El Niño ◽  
Temporal Variability ◽  
El Nino ◽  
Rainfall Variability ◽  
Northeastern Brazil ◽  
Simultaneous Occurrence ◽  
Precipitation Data ◽  
The Pacific ◽  
Dominant Peak

 Pretende-se nesse trabalho investigar como a ODP exerce influência sobre a variabilidade pluviométrica da sub-bacia hidrográfica do Baixo São Francisco, situada na região Nordeste do Brasil. Foram utilizados dados de precipitação de 17 localidades para o período de dados de 1911-1993 obtidos através da Agência Nacional das Águas (ANA) pelo site www.ana.gov.br/hidroweb. O pico dominante para a variabilidade temporal do BSF é da escala de 20,2-22 anos e pico secundário, significativo, ocorre na escala de 11 anos. Durante a ocorrência simultânea de ENOS e ODP negativa, as anomalias positivas aumentaram consideravelmente. O que parece é que a ODP negativa incrementa os valores das anomalias de chuva, tanto durante El Niño, quanto La Niña.Palavras-chave: Oscilação Decadal do Pacífico, Baixo São Francisco, Análise de Ondeletas  Study of the Influence of the Pacific Decadal Oscillation in the Northeast of Brazil  ABSTRACT It is intended this work to investigate how the PDO influence on rainfall variability in the sub-basin of the Lower São Francisco, located in northeastern Brazil. We used precipitation data from 17 sites for the period 1911-1993 data obtained through the National Water Agency (ANA) by the site www.ana.gov.br / hidroweb. The dominant peak for the temporal variability of BSF is the range of 20.2 to 22 years and secondary peak, significantly, occurs in the range of 11 years. During the simultaneous occurrence of ENSO and PDO negative, the positive anomalies have increased considerably. It turns out that the PDO increases the negative values of abnormal rainfall, both during El Niño, and La Niña. Keywords: Pacific Decadal Oscillation, Low São Francisco, Wavelet Analysis

scholarly journals The Hiatus in Global Warming and Interactions between the El Niño and the Pacific Decadal Oscillation: Comparing Observations and Modeling Results

Climate ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 72 ◽  
Author(s):  
Knut Seip ◽  
Hui Wang
Keyword(s):  
Global Warming ◽  
Pacific Decadal Oscillation ◽  
El Niño ◽  
Climate Model ◽  
El Nino ◽  
Global Climate ◽  
Global Climate Model ◽  
The Pacific ◽  
Common Cycles ◽  
Hadley Centre

Ocean oscillations interact across large regions and these interactions may explain cycles in global temperature anomaly, including hiatus periods. Here, we examine ocean interaction measures and compare results from model simulations to observations for El Niño and the Pacific decadal oscillation (PDO). We use the global climate model of the Met Office Hadley Centre. A relatively novel method for identifying running leading-agging LL-relations show that the observed El Niño generally leads the observed PDO and this pattern is strengthened in the simulations. However, LL-pattern in both observations and models shows that there are three periods, around 1910–1920, around 1960 and around 2000 where El Niño lags PDO, or the leading signature is weak. These periods correspond to hiatus periods in global warming. The power spectral density analysis, (PSD), identifies various ocean cycle lengths in El Niño and PDO, but the LL-algorithm picks out common cycles of 7–8 and 24 years that shows leading-lagging relations between them.

scholarly journals Influence of the Pacific Decadal Oscillation on the Relationship between El Niño and the Northeast Asian Summer Monsoon

2010 ◽  
Vol 23 (17) ◽  
pp. 4525-4537 ◽  
Author(s):  
Jinhee Yoon ◽  
Sang-Wook Yeh
Keyword(s):  
Pacific Decadal Oscillation ◽  
El Niño ◽  
El Nino ◽  
Asian Summer Monsoon ◽  
Northeast Asia ◽  
Summer Rainfall ◽  
The Pacific ◽  
Asian Summer ◽  
Northeast Asian ◽  
The Relationship

Abstract The influence of the Pacific decadal oscillation (PDO) on the relationship between El Niño and the northeast Asian summer monsoon (NEASM) is examined using observational datasets for the period of 1979–2007. When El Niño occurs during the boreal winter (December–February), the amount of rainfall over northeast Asia is usually above normal during the following summer (June–August). This relationship between El Niño and the NEASM is intensified when El Niño and the PDO are in phase during the previous winter. However, when El Niño and the PDO are out of phase, the relationship is weakened. The authors argue that the PDO can constructively or destructively interfere with the summer rainfall response over northeast Asia to El Niño. They follow the hypothesis that the summer rainfall over northeast Asia could be separated into two components, that is, the tropics-related component and the extratropics-related component. Then they argue that the PDO could modulate the relationship between El Niño and the NEASM through changes in the extratropics-related rainfall, which is associated with the atmospheric circulation, such as the Eurasian pattern. The conditional composites show that when El Niño and the PDO are in phase, the Eurasian-like pattern acts to enhance the extratropics-related rainfall over northeast Asia, resulting in the strengthening of the NEASM. In contrast, the Eurasian-like pattern acts to reduce the extratropics-related rainfall when El Niño and the PDO are out of phase, resulting in the weakening of the NEASM.

scholarly journals Influences of the El Niño Southern Oscillation and the Pacific Decadal Oscillation on the timing of the North American spring

2011 ◽  
Vol 32 (15) ◽  
pp. 2301-2310 ◽  
Author(s):  
Gregory J. McCabe ◽  
Toby R. Ault ◽  
Benjamin I. Cook ◽  
Julio L. Betancourt ◽  
Mark D. Schwartz
Keyword(s):  
Pacific Decadal Oscillation ◽  
North American ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
The North ◽  
The Pacific

scholarly journals Wintertime Northern Hemisphere Response in the Stratosphere to the Pacific Decadal Oscillation Using the Whole Atmosphere Community Climate Model

2016 ◽  
Vol 29 (3) ◽  
pp. 1031-1049 ◽  
Author(s):  
A. C. Kren ◽  
D. R. Marsh ◽  
A. K. Smith ◽  
P. Pilewskie
Keyword(s):  
Northern Hemisphere ◽  
Pacific Decadal Oscillation ◽  
El Niño ◽  
Climate Model ◽  
El Nino ◽  
Positive Phase ◽  
Late Winter ◽  
Community Climate Model ◽  
The Pacific ◽  
Community Climate

Abstract The response of the Northern Hemisphere winter stratosphere to the Pacific decadal oscillation (PDO) is examined using the Whole Atmosphere Community Climate Model. A 200-yr preindustrial control simulation that includes fully interactive chemistry, ocean and sea ice, constant solar forcing, and greenhouse gases fixed to 1850 levels is analyzed. Based on principal component analysis, the PDO spatial pattern, frequency, and amplitude agree well with the observed PDO over the period 1900–2014. Consistent with previous studies, the positive phase of the PDO is marked by a strengthened Aleutian low and a wave train of geopotential height anomalies reminiscent of the Pacific–North American pattern in the troposphere. In addition to a tropospheric signal, a zonal-mean warming of about 2 K in the northern polar stratosphere and a zonal-mean zonal wind decrease of about 4 m s−1 in the PDO positive phase are found. When compositing PDO positive or negative winters during neutral El Niño years, the magnitude is reduced and depicts an early winter forcing of the stratosphere compared to a late winter response from El Niño. Contamination between PDO and ENSO signals is also discussed. Stratospheric sudden warmings occur 63% of the time in the PDO positive phase compared to 40% in the negative phase. Although this sudden warming frequency is not statistically significant, it is quantitatively consistent with NCEP–NCAR reanalysis data and recent observational evidence linking the PDO positive phase to weak stratospheric vortex events.

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