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The frequencies of the solar acoustic oscillations vary over the activitycycle. The variations in other activity proxies are found to be well correlatedwith the variations in the acoustic frequencies. However, each proxy has aslightly different time behaviour. Our goal is to characterize the differencesbetween the time behaviour of the frequency shifts and of two other activityproxies, namely, the area covered by sunspots and the 10.7cm flux. We define anew observable that is particularly sensitive to the short-term frequencyvariations. We then compare the observable when computed from model frequencyshifts and from observed frequency shifts obtained with the Global OscillationNetwork Group (GONG) for cycle 23. Our analysis shows that on the shortesttime-scales the variations in the frequency shifts seen in the GONGobservations are strongly correlated with the variations in the area covered bysunspots. However, a significant loss of correlation is still found. We verifythat the times when the frequency shifts and the sunspot area do not vary in asimilar way tend to coincide with the times of the maxima of the quasi-biennialvariations seen in the solar seismic data. A similar analysis of the relationbetween the 10.7cm flux and the frequency shifts reveals that the short-timevariations in the frequency shifts follow even more closely those of the 10.7cmflux than those of the sunspot area. However, a loss of correlation betweenfrequency shifts and 10.7cm flux variations is still found around the sametimes.

A thorough analysis of the short- and mid-term activity-related variations in the solar acoustic frequencies