scholarly journals A century of climate variability in central Dronning Maud Land, East Antarctica, and its relation to Southern Annular Mode and El Niño-Southern Oscillation

2010 ◽  
Vol 115 (D16) ◽  
Author(s):  
Sushant S. Naik ◽  
Meloth Thamban ◽  
C. M. Laluraj ◽  
B. L. Redkar ◽  
Arun Chaturvedi
Keyword(s):  
Climate Variability ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
Southern Annular Mode ◽  
East Antarctica ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Annular Mode ◽  
Dronning Maud Land

VARIABILIDAD CLIMÁTICA, CAMBIO CLIMÁTICO Y PESQUERÍAS EN EL ECUADOR.

2012 ◽  
Vol 1 (1) ◽  
Author(s):  
Johnny Chavarría Viteri ◽  
Dennis Tomalá Solano
Keyword(s):  
Climate Change ◽  
Climate Variability ◽  
Pacific Decadal Oscillation ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Current Action ◽  
Palabras Clave

La variabilidad climática es la norma que ha modulado la vida en el planeta. Este trabajo demuestra que las pesquerías y acuicultura costera ecuatorianas no son la excepción, puesto que tales actividades están fuertemente influenciadas por la variabilidad ENSO (El Niño-Oscilación del Sur) y PDO (Oscilación Decadal del Pacífico), planteándose que la señal del cambio climático debe contribuir a esta influencia. Se destaca también que, en el análisis de los efectos de la variabilidad climática sobre los recursos pesqueros, el esfuerzo extractivo también debe ser considerado. Por su parte, la acción actual de la PDO está afectando la señal del cambio climático, encontrándose actualmente en fases opuestas. Se espera que estas señales entren en fase a finales de esta década, y principalmente durante la década de los 20 y consecuentemente se evidencien con mayor fuerza los efectos del Cambio Climático. Palabras Clave: Variabilidad Climática, Cambio Climático, ENSO, PDO, Pesquerías, Ecuador. ABSTRACT Climate variability is the standard that has modulated life in the planet. This work shows that the Ecuadorian  fisheries and aquaculture are not the exception, since such activities are strongly influenced by ENSO variability (El Niño - Southern Oscillation) and PDO (Pacific Decadal Oscillation), considering that the signal of climate change should contribute to this influence. It also emphasizes that in the analysis of the effects of climate variability on the fishing resources, the extractive effort must also be considered. For its part, the current action of the PDO is affecting the signal of climate change, now found on opposite phases. It is hoped that these signals come into phase at the end of this decade, and especially during the decade of the 20’s and more strongly evidencing the effects of climate change. Keywords: Climate variability, climate change, ENSO (El Niño - Southern Oscillation) and PDO  (Pacific Decadal Oscillation); fisheries, Ecuador. Recibido: mayo, 2012Aprobado: agosto, 2012

Observed Relationships between the El Niño–Southern Oscillation and the Extratropical Zonal-Mean Circulation

2006 ◽  
Vol 19 (2) ◽  
pp. 276-287 ◽  
Author(s):  
Michelle L. L’Heureux ◽  
David W. J. Thompson
Keyword(s):  
Zonal Wind ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
Austral Summer ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Annular Mode ◽  
Mean Circulation ◽  
The Impact

Abstract There is increasing evidence indicating that the climate response to variations in the El Niño–Southern Oscillation (ENSO) includes not only thermally forced zonal wind anomalies in the subtropics but also eddy-driven zonal wind anomalies that extend into the mid–high latitudes of both hemispheres. In this study, new insights into the observed seasonally varying signature of ENSO in the extratropical zonal-mean circulation are provided and the associated linkages with the dominant patterns of extratropical variability are examined. The zonal-mean extratropical atmospheric response to ENSO is characterized by two principal features: an equivalent barotropic dipole in the Southern Hemisphere (SH) zonal-mean zonal flow with centers of action located near ∼40° and ∼60° during austral summer, and a weaker, but analogous, dipole in the Northern Hemisphere (NH) with centers of action located near ∼25° and ∼45° during early and late boreal winter. Both structures are accompanied by eddy momentum flux anomalies that exhibit a remarkable degree of hemispheric symmetry. In the SH, the extratropical signature of ENSO projects strongly onto the primary mode of large-scale variability, the southern annular mode (SAM). During the austral summer, roughly 25% of the temporal variability in the SAM is linearly related to fluctuations in the ENSO cycle. An analogous relationship is not observed in association with the principal mode of climate variability in the NH, the northern annular mode (NAM). It is argued that the seasonally varying impact of ENSO on the extratropical circulation is consistent with the impact of the thermally forced subtropical wind anomalies on the dissipation of equatorward-propagating wave activity at subtropical latitudes.

El Niño Southern Oscillation and decadal climate variability impacts on crop yields and adaptation value.

2021 ◽  
Vol 16 (43) ◽  
pp. 1-13
Author(s):  
Minglu Wang ◽  
◽  
Yu-Kai Huang ◽  
Muxi Cheng ◽  
Bingru Sheng ◽  
...  
Keyword(s):  
Climate Variability ◽  
El Niño ◽  
Crop Yields ◽  
El Nino ◽  
Southern Oscillation ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Decadal Climate Variability ◽  
Research Issues ◽  
Decadal Climate

Ocean-atmospheric phenomena (OAP) have been found to be associated with regional climate variability and, in turn, agricultural production. Previous research has shown that advance information on OAP and its climate implications could provide valuable opportunities to adjust agriculture practices. In this study, we review OAP effects on crop yields, covering both shorter-term El Niño Southern Oscillation (ENSO) and longer-term ocean-related decadal climate variability (DCV) phenomena, such as Pacific Decadal Oscillation (PDO), the Tropical Atlantic Gradient (TAG), and the West Pacific Warm Pool (WPWP). We review both statistical approaches and simulation models that have been used to assess OAP impacts on crop yields. Findings show heterogeneous impacts across crops, regions, OAP phases, and seasons. Evidence also indicates that more frequent and extreme OAP phases would damage agriculture. However, economic gains could be achieved via adaptation strategies responding to the early release of OAP phase information. Discussions on current knowledge gaps and future research issues are included.

scholarly journals An Investigation of Extreme Cold Events at the South Pole

2021 ◽  
pp. 1-35
Keyword(s):  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
Southern Annular Mode ◽  
El Nino Southern Oscillation ◽  
South Pole ◽  
The South ◽  
Annular Mode ◽  
Cold Events ◽  
Extreme Cold

Abstract From 5 July to 11 September 2012, the Amundsen-Scott South Pole station experienced an unprecedented 78 days in a row with a maximum temperature at or below -50°C. Aircraft and ground-based activity cannot function without risk below this temperature. Lengthy periods of extreme cold temperatures are characterized by a drop in pressure of around 15 hPa over four days, accompanied by winds from grid east. Periodic influxes of warm air from the Weddell Sea raise the temperature as the wind shifts to grid north. The end of the event occurs when the temperature increase is enough to move past the -50°C threshold. This study also examines the length of extreme cold periods. The number of days below -50°C in early winter has been decreasing since 1999, and this trend is statistically significant at the 5% level. Late winter shows an increase in the number of days below -50°C for the same period, but this trend is not statistically significant. Changes in the Southern Annular Mode, El Niño Southern Oscillation, and the Interdecadal Pacific Oscillation/Tripole Index are investigated in relation to the initiation of extreme cold events. None of the correlations are statistically significant. A positive Southern Annular Mode and a La Niña event or a central Pacific El Niño Southern Oscillation pattern would position the upper-level circulation to favor a strong, symmetrical polar vortex with strong westerlies over the Southern Ocean, leading to a cold pattern over the South Pole.

scholarly journals Climate Impacts on Density Altitude and Aviation Operations

2018 ◽  
Vol 57 (3) ◽  
pp. 517-523 ◽  
Author(s):  
Christopher J. Goodman ◽  
Jennifer D. Small Griswold
Keyword(s):  
Climate Variability ◽  
El Niño ◽  
Arctic Oscillation ◽  
El Nino ◽  
Southern Oscillation ◽  
The Arctic ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Aircraft Performance ◽  
The Arctic Oscillation

AbstractA critical determinant of aircraft performance is density altitude, or the density given as a height above mean sea level, which is dependent on air temperature, pressure, and humidity. These meteorological variables change on various time scales (e.g., hourly, seasonal, and decadal) and are regionally impacted by large-scale climate variability as the result of phenomena such as El Niño–Southern Oscillation or the Arctic Oscillation. Here a statistical analysis is performed to determine the impacts of climate variability on seasonally averaged density altitude, a key metric used by pilots to determine aircraft performance and efficiency, as a function of El Niño–Southern Oscillation and the Arctic Oscillation using NCEP–NCAR reanalysis data and historical aviation meteorological records. Regressions show regional dependencies and impacts to density altitudes that vary as a function of season for both El Niño–Southern Oscillation and Arctic Oscillation cases. The results highlight the importance of understanding the regional nature of the impact of climate variability on density altitude and the potential impacts on aviation operations.

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