4784 20200210134310.0 POSTER-2020-0060 Wauters, Laurence Evolution of periodicities with solar cycle for long-term solar time series 2019 2019-11-18 The periodograms of the spacial PROBA2/LYRA data show predominant periodicities comparable to the ones observed by other solar time series for the same time range. These periodicities have been found to slightly vary over time. Tracking their evolution on a long-term basis aims at identifying which periodicities are related to each other and at determining which physical processes are at their origin. A study has been made on ground based sunspot area (total and hemispheric), for which several solar cycles of data exist and for which the periodicities are close to the ones found in PROBA2/LYRA (for the same time range). We used framed Lomb-Scargle periodograms to extract the periodicities and check their evolution. Several significant periodicities behave similarly and seem to be harmonics of each other. The differential solar rotation and the magnetic solar cycle are highlighted by the results. PRO-SIDC/ PRO-SIDC/ PRO-SIDC NO Dominique, Marie Dammash, Ingolf I.E Meftah, Mustafa ESWW16, Liège laurence.wauters@observatoire.be https://register-as.oma.be/esww16/contributions/public/S3-P1/S3-P1-28-WautersLaurence/ESWW16_LW.pptx CPOSTER