UARS MLS GW observations over the southern Andes provide a good example that satellite limb techniques can adaquately detect mountain waves generated by topography. Located near the edge of the stratospheric jetstream, the southern Andes is often exposed to the strong background winds during the Antarctic winter season, which establishs a favorable condition for gravity waves to propagate in the middle atmosphere. This figure shows MLS limb-scan variances at ~38 km altitude in the vicinity of the Andes, which are computed using 4-point truncation at the bottom of each scan and averaged into 4deg x 10 deg latitude-longitude grids. The wave activities are significantly enhanced over the southern Andes and the tip of the Antarctic Peninsula. The influence of the topography is extended in a long tail toward the east over Drake Passage and Scotia Sea. [Jiang et al. 2002].