Global Internal Tides from Altimetry: results

Internal tides around the Hawaiian Ridge and beyond

 Zhongxiang has used his multi-satellite technique to separate the long-distance propagating waves from the Aleutians and Hawaii.  In the movie, the southbound and northbound waves are seen separately at left and center.  Remember that these are data, not a model!  Notice how they each travel over 3500 km - to cross the entire basin.  The two wavefields together (right) is much more confused, showing a complicated interference pattern.

The following two figures show a zoom-in of these fields around Hawaii.

Energy flux of mode-1 (upper panel) and mode-2 (lower panel) Minternal tides around the Hawaiian Ridge, estimated from multi-satellite altimetry using 120 km by 120 km fitting region. The 4000 m isobath contours are shown in gray. Remarkable generation sites are labeled: Midway Island (MI), Lisianski Island (LiI), Laysan Island (LaI), Gardner Pinnacles (GP), French Frigate Shoals (FFS), Nihoa Island (NI), and Kauai Channel (KC). Red and green arrows indicate southward and northward internal tides, respectively. Flux arrows smaller than 0.15 kW/m are not plotted. The gray boxes show the five areas used in the Princeton Ocean Model runs by Merrifield and Holloway  [2002].  [work conducted from Zhao, Alford, Girton, Carter, and Johnston, JGR Oceans, 2011]