Observations have revealed the existence of weak transient disturbances in extended coronal loop systems. These propagating disturbances (PDs) originate from small scale brightenings at the footpoints of the loops and propagate upward along the loops. In all cases observed, the projected propagation speed is close to, but below the expected sound speed in the loops. This suggest that the PDs could be interpreted as slow mode MHD waves. Interpreting the oscillations in terms of di?erent wave modes and/or plasma motions always depend on the line of sight as we observe on the limb or on the center of the disk. The JOP 165 campaign will address some of these questions. MDI, SPIRIT and TRACE photospheric and UV images have been acquired simultaneously with high temporal and spatial coverage along with spectroscopic data from CDS.Some of the o?-limb active region dynamics and oscillations observed during this JOP campaign is presented here. Particularly, detection of plasma condensations and temporal variations in active region loops are discussed.
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