scholarly journals Relation of size and displacement of the 300 mbar north circumpolar vortex to QBO, El Nino, and sunspot number, 1963-2000

2001 ◽  
Vol 106 (D23) ◽  
pp. 31787-31794 ◽  
Author(s):  
James K. Angell
Keyword(s):  
Sunspot Number ◽  
El Niño ◽  
El Nino ◽  
Circumpolar Vortex

Changes in the 300-mb North Circumpolar Vortex, 1963–2001

2006 ◽  
Vol 19 (12) ◽  
pp. 2984-2994 ◽  
Author(s):  
James K. Angell
Keyword(s):  
El Niño ◽  
El Nino ◽  
Western Hemisphere ◽  
Quasi Biennial Oscillation ◽  
Circumpolar Vortex ◽  
Eastern Hemisphere ◽  
University Of Berlin ◽  
El Chichón ◽  
Vortex Size ◽  
El Chichon

Abstract The mean monthly polar stereographic map analyses of the Free University of Berlin terminated at the end of 2001. This paper summarizes the changes in size of the 300-mb north circumpolar vortex, and quadrants, for the full period of record, 1963–2001, where the size has been defined by planimetering the area poleward of contours in the jet stream core. A contracted vortex has tended to be a deep vortex in winter but a shallow vortex in summer. During 1963–2001 there was a statistically significant decrease in vortex size of 1.5% per decade, the decrease in size of Western Hemisphere quadrants being twice that of Eastern Hemisphere quadrants. A significant increase in Arctic Oscillation (AO) index accompanies the significant decrease in vortex size, but since the vortex contracts appreciably in all four seasons, whereas the positive trend in the AO index is mainly in winter, the vortex cannot serve as a proxy for the AO index. The evidence for vortex contraction at the time of the 1976–77 regime shift is not conclusive, but there is good evidence for a 6% increase in vortex size due to the 1991 Pinatubo eruption. There is little change in vortex size following the 1982 El Chichon eruption, however. Because on average there is a significant 4% contraction of the vortex following an El Niño, it is proposed that the vortex expansion to be expected following the 1982 El Chichon eruption has been contravened by the contraction following the strong 1982–83 El Niño. There is little relation between vortex size and phase of the quasi-biennial oscillation (QBO), and the evidence for a contracted vortex near 11-yr sunspot maxima is tenuous because the vortex record extends through only three full sunspot cycles. There is a highly significant tendency for opposite vortex quadrants 0°–90°E and 90°W–180° to vary in size together, indicating either a pulsating polar vortex or the propagation of planetary wavenumber 2.

Relationship of cholera incidence to El Niño and solar activity elucidated by time-series analysis

2009 ◽  
Vol 138 (1) ◽  
pp. 99-107 ◽  
Author(s):  
K. OHTOMO ◽  
N. KOBAYASHI ◽  
A. SUMI ◽  
N. OHTOMO
Keyword(s):  
Time Series ◽  
Solar Activity ◽  
Time Series Analysis ◽  
Surface Temperature ◽  
Sunspot Number ◽  
El Niño ◽  
El Nino ◽  
Sea Surface ◽  
Series Analysis ◽  
Relationship Of

SUMMARYUsing time-series analysis, we investigated the monthly cholera incidence in Dhaka, Bangladesh during an 18-year period for its relationship to the sea surface temperature (SST) linked to El Niño, and to the sunspot number. Dominant periodic modes identified for cholera incidence were 11·0, 4·8, 3·5, 2·9, 1·6, 1·0 and 0·5 years. The majority of these modes, e.g. the 11·0-, 4·8-, 3·5-, 1·6- and 1·0-year modes, were essentially consistent with those obtained for the SST data (dominant modes: 5·1, 3·7, 2·5, 2·1, 1·5, 1·0 years) and the sunspot number data (dominant modes: 22·1, 11·1, 7·3, 4·8, 3·1 years). We confirmed that the variations of cholera incidence were synchronous with SSTs, and were inversely correlated to the sunspot numbers. These results suggest that the cholera incidence in Bangladesh may have been influenced by the occurrence of El Niño and also by the periodic change of solar activity.

scholarly journals Response of Extreme Precipitation to Solar Activity and El Nino Events in Typical Regions of the Loess Plateau

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
H. J. Li ◽  
J. E. Gao ◽  
H. C. Zhang ◽  
Y. X. Zhang ◽  
Y. Y. Zhang
Keyword(s):  
Solar Activity ◽  
Loess Plateau ◽  
Sunspot Number ◽  
El Niño ◽  
Extreme Precipitation ◽  
El Nino ◽  
Southern Oscillation ◽  
The Loess Plateau ◽  
El Niño Events ◽  
El Nino Events

Extreme climatic oscillation has been the subject of global attention. The purpose of this study is to explore the response of extreme precipitation to solar activity and El Nino events in typical regions of the Loess Plateau—a case study in the Yan’an area. The precipitation data was from nine weather stations in Yan’an and the sunspot number and the Southern Oscillation Index (SOI) were from 1951 to 2015. The results show that maximum precipitation occurred mainly at the peak sunspot number or 2a near it and the sunspot number minimum and valley values were not significantly correlated. The results of Morlet wavelet showed that a 41-year period of precipitation was the most obvious within the 64-year scale. Similarly, sunspot number showed a 16-year periodic variability. Correlation analyses of the 16-year and 41-year scales demonstrated that the relationships between precipitation and sunspot number were close. In addition, extreme precipitation often occurred in the year following El Nino events. According to 10-year moving average curves, precipitation generally showed a downward trend when SOI was negative. The results indicate that solar activity and El Nino events had significant impacts on precipitation in typical regions of the Loess Plateau.

Statistics of Solar Cycle–La Niña Connection: Correlation of Two Autocorrelated Time Series

2012 ◽  
Vol 69 (10) ◽  
pp. 2934-2939 ◽  
Author(s):  
Eddie Haam ◽  
Ka-Kit Tung
Keyword(s):  
Time Series ◽  
Solar Cycle ◽  
Sunspot Number ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
La Niña ◽  
Cold Event ◽  
La Nina ◽  
Instrumental Records

Abstract Both the 11-yr solar cycle and the El Niño–Southern Oscillation (ENSO) phenomena are quasi periodic, with periods of 9–11 and 3–4 yr, respectively. There have been claims that the two are correlated, with the sun at its peak in sunspot number presumably forcing a cold event in the equatorial Pacific. However, both phenomena are also highly autocorrelated. Caution should be exercised when testing for the statistical significance of the correlation of two autocorrelated time series. The solar peak years can coincide with cold ENSO by chance, even if the two time series are independent, and the coincidence then persists for many cycles due to their autocorrelation, before drifting apart. This study demonstrates that this is indeed the case using the Quinn El Niño index (1525–1987), which is a chronicle of observations of El Niño–related events, and the sunspot number (SSN) series going back to 1750. Appropriate statistical tests are suggested that can test for correlation, taking into account autocorrelation applicable to the shorter instrumental records. There is so far no solar peak–La Niña connection found that is statistically significant.

Alopecia en el niño

2020 ◽  
Vol 55 (4) ◽  
pp. 1-14
Author(s):  
K. Legal ◽  
P. Plantin
Keyword(s):  
El Niño ◽  
El Nino

Alopecia en el niño

2020 ◽  
Vol 54 (3) ◽  
pp. 1-15
Author(s):  
K. Legal ◽  
P. Plantin
Keyword(s):  
El Niño ◽  
El Nino

Resección-reconstrucción en tumores óseos malignos en el niño

2018 ◽  
Vol 10 (2) ◽  
pp. 1-18
Author(s):  
C. Thévenin-Lemoine ◽  
F. Accadbled ◽  
J. Sales de Gauzy
Keyword(s):  
El Niño ◽  
El Nino
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