Science Update: Effect of seasonal cycle of orographic wave occurrence above small Southern Hemisphere islands on general circulation

A new JGR article by M. J. Alexander and A. W. Grimsdell focuses on the orographic gravity waves generated by flow over the topography of small islands in the southern oceans. They use AIRS observations to examine the frequency of occurrence of these waves above 14 islands at ∼40km altitude. They show that these waves occur most frequently from May to September, but not every day. Seasonal variations are observed at different islands and appear to be closely related to latitude and prevailing wind patterns. Further examination indicates that stratospheric winds have a first-order limiting effect of these island mountain waves. The full abstract can be found here.