{"title":"Is the variability of ENSO due to frequency modulation by the long term variation in solar activity?","authors":"Ian Edmonds , Peter Killen","doi":"10.1016/j.jastp.2025.106490","DOIUrl":null,"url":null,"abstract":"<div><div>The spectral content of the El Nino Southern Oscillation (ENSO) is broad and complex, a characteristic shared by other climate variables. Spectral analysis of ENSO in different time intervals demonstrated that ENSO is frequency modulated. An analytical model in which the natural period of ENSO is frequency modulated by long term centennial range variation in solar activity was developed and shown to correlate well with the observed ENSO and reconstructed ENSO variation in the decadal periodicity range. A method for identifying the occurrence and the period of frequency modulation in climate variables was developed and tested.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"269 ","pages":"Article 106490"},"PeriodicalIF":1.8000,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Atmospheric and Solar-Terrestrial Physics","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1364682625000744","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
The spectral content of the El Nino Southern Oscillation (ENSO) is broad and complex, a characteristic shared by other climate variables. Spectral analysis of ENSO in different time intervals demonstrated that ENSO is frequency modulated. An analytical model in which the natural period of ENSO is frequency modulated by long term centennial range variation in solar activity was developed and shown to correlate well with the observed ENSO and reconstructed ENSO variation in the decadal periodicity range. A method for identifying the occurrence and the period of frequency modulation in climate variables was developed and tested.
期刊介绍:
The Journal of Atmospheric and Solar-Terrestrial Physics (JASTP) is an international journal concerned with the inter-disciplinary science of the Earth''s atmospheric and space environment, especially the highly varied and highly variable physical phenomena that occur in this natural laboratory and the processes that couple them.
The journal covers the physical processes operating in the troposphere, stratosphere, mesosphere, thermosphere, ionosphere, magnetosphere, the Sun, interplanetary medium, and heliosphere. Phenomena occurring in other "spheres", solar influences on climate, and supporting laboratory measurements are also considered. The journal deals especially with the coupling between the different regions.
Solar flares, coronal mass ejections, and other energetic events on the Sun create interesting and important perturbations in the near-Earth space environment. The physics of such "space weather" is central to the Journal of Atmospheric and Solar-Terrestrial Physics and the journal welcomes papers that lead in the direction of a predictive understanding of the coupled system. Regarding the upper atmosphere, the subjects of aeronomy, geomagnetism and geoelectricity, auroral phenomena, radio wave propagation, and plasma instabilities, are examples within the broad field of solar-terrestrial physics which emphasise the energy exchange between the solar wind, the magnetospheric and ionospheric plasmas, and the neutral gas. In the lower atmosphere, topics covered range from mesoscale to global scale dynamics, to atmospheric electricity, lightning and its effects, and to anthropogenic changes.