Movie showing daily data from NASA GPM merged precipitation (a; mm/day), CMEMS merged gridded altimetry sea level anomalies (b; cm), NOAA optimally interpolated sea surface temperature from AVHRR (c; °C), and SMAP-CAPv4.2 (JPL) sea surface salinity (d; psu) for a 51-day composite progression of the 30-90-day intraseasonal oscillation in the Indian Ocean and Bay of Bengal for the 2019 southwest monsoon season. Composites were created based on a box-averaged time series of GPM precipitation over the Indian Ocean (20°S-20°N, 40°E-100°E) for the 2019 southwest monsoon season. The eastward propagation of the Madden-Julian Oscillation (one of the coupled ocean-atmosphere oscillation) is apparent, with a peak at day 26. The northward progression of the associated boreal summer intraseasonal oscillation can be seen clearly between days 24 and 36 as it branches off from the main Madden-Julian Oscillation system and propagates northward through the Bay of Bengal. Both the preconditioning and oceanic response to these intraseasonal oscillations can be seen in SLA, SST, and SSS. SLA in particular shows both the planetary wave propagation in the equatorial region, as well as the dynamic response to the boreal summer intraseasonal oscillation in the Bay of Bengal. (Credit University of South Carolina)