- Reexamine nesting BC algorithm for Uhat
    - scheme 0:  as is:  Interpolate Ubaro(n+1).  Use in vertically integrated
                         momentum equation to generate boundary values for
                         Uhat(n+1)

    - scheme 1:  Directly interpolate Uhat(n+1) from big to small domain.
                         (requires big domain to interpolate different
                          variable.  Requires small domain to by-pass
                          constructing boundary values from momentum eq.)

    - scheme 2:  Also update large domain cell value that only contains fine
                 domain boundary cells.  (e.g. 2/3 original-coarse-value +
                 1/3 average-of-fine-values)
                   - can be combined with other schemes

    - scheme 3:  use scheme 0 but with interpolated Uhat(n-1).  No longer
                 certain what that means.

    - The Uhats in schemes 0 & 1 are, in the coarse grid, the same to 3rd order.
          scheme 0 advantage:  it contains fine scale data in the BCs
          scheme 1 advantage: it contains Large-scale data outside domain at
                   time n+1.  Scheme 0 only has partial large scale Uhat
                   data at time (n+1).

- Construct a list of the various simplifications to the nesting scheme and what
  it would entail to code them for comparison in paper.

    - one-way
    - "explicit" two-way nesting
         need to change order of operations. 1 man-hr to code.
    - not updating RHS of coarse barotropic momentum before constructing
      surface pressure.
         need to skip a section of code.  30 man-minutes to code.

- Going more complicated

    - Update eta(n+1) in interior of large domain instead of eta(n)
      Include all necessary supporting updates.
    - Instead of interpolating eta(n+1) at boundaries, pass coarse grid
      data used for the interpolation.  Formulate deta BC's so boundary
      data will be consistent with updated coarse domain.

- Incorporate volume change updates with nesting updates

    - Merge what we have now.

    - see if need similar updates on nesting (pass volume integrals,
      rescale with final, updated, volumes).