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     Ingrid:
     HTMLwords
    WORLDBATH[bath
]
    grid: /X  (degree_east) periodic (0) to (0.08334351W) by 0.08333333 N= 4320 pts :grid
    grid: /Y  (degree_north) ordered (90.04166S) to (90.04166N) by 0.08333333 N= 2162 pts :grid
    $partialdiff sub Y$   $integral dX$   $integral dY$   detrended-bfl [ WORLDBATH bath ]      [ X | Y] |