scholarly journals Prediction of southern oscillation index using spectral components

MAUSAM ◽  
2022 ◽  
Vol 53 (2) ◽  
pp. 165-176
Author(s):  
R. P. KANE
Keyword(s):  
El Niño ◽  
Southern Oscillation Index ◽  
El Nino ◽  
Southern Oscillation ◽  
Spectral Characteristics ◽  
Singular Spectrum Analysis ◽  
Dependent Data ◽  
Simple Method ◽  
Single Wave ◽  
Using Data

The time series of SOI (Southern Oscillation Index, Tahiti minus Darwin sea-level atmospheric pressure difference) was spectrally analysed by a simple method MEM-MRA, where periodicities are detected by MEM (Maximum Entropy Method) and used in MRA (Multiple Regression Analysis) to get the estimates of their amplitudes and phases. From these, the three or four most prominent ones were used for reconstruction and prediction. Using data for 1935-80 as dependent data, the reconstructed values of SOI matched well with observed values and most of the El Niños (SOI minima) and La Niñas (SOI maxima) were located correctly. But for the independent data (1980 onwards), the matching was poor. Omitting earlier data, 1945- 80, 1955-80, 1965-80 as dependent data again gave poor matching for 1980 onwards. When data for 1980 onwards only were used as dependent data, the matching was better, indicating that the spectral characteristics have changed considerably with time and recent data were more appropriate for further predictions. The 1997 El Niño was reproduced only in data for 1985 onwards. For 1990 onwards, only a single wave of 3.5 years was appropriate and explained the 1997 and 1994 events but only one (1991) of the 3 complex and quick events that occurred during 1989-95. The UCLA group of Dr. Ghil has been using the SSA (Singular Spectrum Analysis)-MEM combination for SOI analysis. For the 1980s, they got very good matching, but the 1989-95 structures were not reproduced. For recent years, their SSA-filtered SOI (used for prediction) is a simple sinusoid of ~3.5 years. It predicted the El Niño of 1997 only at its peak and even after using data up to February 1997, the abrupt commencement of the event in March 1997 and its abrupt end in June 1998 could not be predicted.   Using only a 3.5 years wave, an El Niño was expected for 2000-2001. However, a very long-lasting La Niña seems to be operative and there are no indications as yet (September of 2001) of any El Niño like conditions.

scholarly journals A first shallow firn-core record from Glaciar La Ollada, Cerro Mercedario, central Argentine Andes

2006 ◽  
Vol 43 ◽  
pp. 14-22 ◽  
Author(s):  
David Bolius ◽  
Margit Schwikowski ◽  
Theo Jenk ◽  
Heinz W. Gäggeler ◽  
Gino Casassa ◽  
...  
Keyword(s):  
El Niño ◽  
Southern Oscillation Index ◽  
El Nino ◽  
Southern Oscillation ◽  
Winter Precipitation ◽  
Time Span ◽  
Paleoclimate Reconstruction ◽  
Central Chile ◽  
Annual Layer ◽  
Firn Core

AbstractIn January 2003, shallow firn cores were recovered from Glaciar Esmeralda on Cerro del Plomo (33°14’S, 70°13’W; 5300 ma.s.l.), central Chile, and from Glaciar La Ollada on Cerro Mercedario (31°58’S, 70°07’W; 6070 ma.s.l.), Argentina, in order to find a suitable archive for paleoclimate reconstruction in a region strongly influenced by the El Nino-Southern Oscillation. In the area between 28°S and 35°S, the amount of winter precipitation is significantly correlated to the Southern Oscillation Index, with higher values during El Nino years. Glaciochemical analysis indicates that the paleo-record at Glaciar La Ollada is well preserved, whereas at Glaciar Esmeralda the record is strongly influenced by meltwater formation and percolation. A preliminary dating of the Mercedario core by annual-layer counting results in a time-span of 17 years (1986-2002), yielding an average annual net accumulation of 0.45 m w.e.

scholarly journals An Analysis of the Energetics of Tropical and Extra-Tropical Regions for Warm ENSO Composite Episodes

2017 ◽  
Vol 32 (1) ◽  
pp. 39-51
Author(s):  
Zayra Christine Sátyro ◽  
José Veiga
Keyword(s):  
Kinetic Energy ◽  
Potential Energy ◽  
El Niño ◽  
Energy Production ◽  
El Nino ◽  
Southern Oscillation ◽  
Stable Condition ◽  
The Other ◽  
Tropical Regions ◽  
Using Data

Abstract This study focuses on the quantification and evaluation of the effects of ENSO (El Niño Southern Oscillation) warm phases, using a composite of five intense El Niño episodes between 1979 – 2011 on the Energetic Lorenz Cycle for four distinct regions around the globe: 80° S – 5° N (region 1), 50° S – 5° N (region 2), 30° S – 5° N (region 3), and 30° S – 30° N (region 4), using Data from NCEP reanalysis-II. Briefly, the results showed that zonal terms of potential energy and kinetic energy were intensified, except for region 1, where zonal kinetic energy weakened. Through the analysis of the period in which higher energy production is observed, a strong communication between the available zonal potential and the zonal kinetic energy reservoirs can be identified. This communication weakened the modes linked to eddies of potential energy and kinetic energy, as well as in the other two baroclinic conversions terms. Furthermore, the results indicate that for all the regions, the system itself works to regain its stable condition.

scholarly journals KAJIAN STATISTIK UKURAN BESAR BUTIR SEDIMEN DAN KAITANNYA DENGAN VARIABILITAS IKLIM MUSIMAN DAN TAHUNAN DI MUARA GEMBONG, TELUK JAKARTA

2019 ◽  
Vol 11 (3) ◽  
pp. 683-695 ◽  
Author(s):  
Taufik R. Syachputra ◽  
Ivonne M. Radjawane ◽  
Rina Zuraida
Keyword(s):  
El Niño ◽  
Southern Oscillation Index ◽  
El Nino ◽  
Southern Oscillation ◽  
El Nino Southern Oscillation ◽  
Dipole Mode ◽  
Australian Monsoon ◽  
Dipole Mode Index ◽  
Monsoon Index ◽  
Mode Index

Variabilitas iklim dapat mempengaruhi sifat sedimen yang terendapkan di dasar laut. Salah satu sifat sedimen yang dipengaruhi oleh iklim adalah besar butir. Penelitian ini bertujuan untuk menguji hubungan antara besar butir dengan variabilitas iklim menggunakan sampel core GM01-2010-TJ22 dari Muara Gembong, Teluk Jakarta, muara sungai Citarum. Sampel core diambil pada tahun 2010 dengan menggunakan Kapal Riset Geomarin I oleh Pusat Penelitian dan Pengembangan Geologi Kelautan (P3GL). Pengukuran besar butir dilakukan dengan menggunakan Mastersizer 2000. Hasil pengukuran ditampilkan dalam seri waktu dari tahun 2001 sampai 2010. Hasil analisis besar butir sampel sedimen dikorelasikan secara statistik dengan fenomena musiman (monsun), tahunan dan antar tahun (El Niño/La Niña dan Dipole Mode). Verifikasi data dilakukan dengan menggunakan data sekunder temperatur permukaan laut dari citra satelit di sekitar lokasi sampel dan data curah hujan di Bekasi. Hasil verifikasi menunjukkan bahwa peningkatan curah hujan di sekitar daerah hilir Sungai Citarum diikuti dengan penurunan temperatur permukaan laut dan peningkatan ukuran rata-rata besar butir. Hasil yang didapat dalam uji statistika menunjukkan bahwa perubahan ukuran besar butir sampel sedimen di Muara Gembong memiliki korelasi signifikan dengan Multivariate ENSO (El Niño Southern Oscillation) Index (MEI), Ocean Niño Index (ONI), Dipole Mode Index (DMI) dan Australian Monsoon Index (AUSMI). Hasil tersebut menunjukkan bahwa besar butir sedimen dasar laut potensial digunakan untuk mengetahui variabilitas iklim di sekitar Teluk Jakarta.

Classification of El Niño and La Niña years for water resources management in Alberta

2018 ◽  
Vol 45 (12) ◽  
pp. 1093-1098
Author(s):  
Zahidul Islam
Keyword(s):  
Water Resources ◽  
Water Resources Management ◽  
El Niño ◽  
El Nino ◽  
Southern Oscillation ◽  
La Niña ◽  
Simple Method ◽  
Resources Management ◽  
La Nina

Classification of El Niño and La Niña years in a historical time period is necessary to analyze their impacts on hydrology and water resources management. In this study, various El Niño-Southern Oscillation (ENSO) indices, and how they are used to classify El Niño or La Niña years have been reviewed. Based on the review, a simple method of classifying El Niño or La Niña years has been proposed.

scholarly journals The Correlation of Southern Oscillation Index (SOI) with the Rainfall at Rainy and Dry Season Peak in Kintamani-Bangli Region period 1986-2015

2019 ◽  
Vol 20 (2) ◽  
pp. 6
Author(s):  
Wayan Mita Restitiasih ◽  
I Ketut Sukarasa ◽  
I Wayan Andi Yuda
Keyword(s):  
Correlation Coefficient ◽  
El Niño ◽  
Southern Oscillation Index ◽  
El Nino ◽  
Southern Oscillation ◽  
Management Plan ◽  
Correlation Study ◽  
Dry Season ◽  
Rainfall Data ◽  
The Relationship

A correlation study of the Southern Oscillation Index (SOI) on rainfall at the peak of the wet and dry season in the Kintamani-Bangli region has been carried out by taking SOI values and rainfall data for the period 1986-2015. The rainfall data used were recorded at 2 rain posts, namely Kembangsari and Kintamani. The research aimed to determine the relationship of fluctuations in the value of SOI with the intensity of rainfall, so that it can be used as a regional management plan when El Nino occurs. The method used in this study is correlation. The results obtained from the correlation that is the relationship between SOI value and rainfall in February were quite strong in the Kembangsari post with correlation coefficient of 0.409. Whereas for the Kintamani post the correlation obtained was weak with a correlation coefficient of 0.308. Then in August a weak correlation occurred in the Kembangsari post with a correlation coefficient of 0.2398 and was quite strong in the Kintamani post with a correlation coefficient of 0.4662. So that the influence of El Nino in the Kintamani area in February was more dominant in the Kembangsari post and in August at the Kintamani post.

scholarly journals KORELASI INDEKS NINO 3.4 DAN SOUTHERN OSCILLATION INDEX (SOI) DENGAN VARIASI CURAH HUJAN DI SEMARANG

2018 ◽  
Vol 19 (2) ◽  
pp. 75
Author(s):  
Anistia Malinda Hidayat ◽  
Usman Efendi ◽  
Lisa Agustina ◽  
Paulus Agus Winarso
Keyword(s):  
El Niño ◽  
Southern Oscillation Index ◽  
El Nino ◽  
Southern Oscillation ◽  
El Niño Southern Oscillation ◽  
El Nino Southern Oscillation

Semarang merupakan salah satu wilayah di Indonesia yang rawan terdampak bencana hidrometeorologi. Sejumlah wilayah di Semarang merupakan daerah rawan kekeringan, sementara di wilayah lainnya merupakan daerah langganan banjir tiap tahunnya. Salah satu parameter yang memiliki keterkaitan erat dengan fenomena hidrometeorologi adalah El Nino Southern Oscillation (ENSO). Sebagai sirkulasi tropis non musiman, ENSO memiliki peran penting terhadap variasi curah hujan yang diamati. Penelitian terkait ENSO telah banyak dilakukan sebelumnya, namun belum ada penelitian tekait yang dilakukan di Semarang yang notabene merupakan daerah rawan bencana hidrometeorologi, sehingga fluktuasi ENSO menarik untuk dikaji di wilayah ini. Penelitian ini bertujuan untuk menganalisis korelasi fenomena global laut atmosfer terhadap distribusi curah hujan di wilayah Semarang. Dalam jangka waktu 15 tahun (2001-2015), pengaruh dari ENSO dianalisis menggunakan korelasi temporal untuk menentukan dampak dari ENSO pada curah hujan yang diamati di enam pos pengamatan hujan di Semarang. Analisis tersebut menunjukkan bahwa korelasi antara anomali Suhu Permukaan Laut (SPL) di wilayah Nino 3.4 dengan curah hujan diamati secara signifikan pada lima pos pengamatan hujan selama periode September Oktober November (SON) dengan rentang nilai korelasi antara -0.598 sampai dengan -0.679. Sementara itu, korelasi variabilitas curah hujan dengan Southern Oscillation Index (SOI) menunjukan nilai yang berkisar antara 0.561 sampai dengan 0.780. Curah hujan yang diamati umumnya selalu berkurang pada tahun-tahun dimana nilai indeks Nino 3.4 positif dan nilai SOI negatif, sedangkan curah hujan diamati meningkat pada tahun-tahun dimana nilai indeks Nino 3.4 negatif dan nilai SOI yang positif.

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