Striking 20--30-day sea surface temperature waves observed along the equatorial front in the later half of the year are generally believed to be of an oceanic origin. Here we report the detection of atmospheric waves that are unambiguously tied to these oceanic waves, using new satellite measurements of surface winds. A general circulation model simulation reveals that these atmospheric waves have a shallow vertical structure trapped in the planetary boundary layer (PBL), unlike El Nino/Southern Oscillation where changes in deep convection are the cause of anomalous winds. Vertical wave motion penetrates well above the PBL and is likely to impact the distribution and transport of climatically important gas species such as ozone and dimethyl sulfide. ¿ 1998 American Geophysical Union