One aspect of ENSO that I haven't analyzed too deeply is the spatial part of the standing wave dipole. In solving Laplace's Tidal Equations, the separation of the partial diffEq leads to a family of terms
sin(a f(t)) sin(k a x) + sin(b f(t)) sin(k b x) + ...
where f(t) is the tidal forcing and a & b are the two strongest terms in any model fit, corresponding to the main dipole and a higher wavenumber solution.
Each spatial term is simply a sine wave with a wavenumber proportional to the a,b,.. value, with a phase aligned to the oceanic boundary conditions.
So the a term is locked to a dipole that spans the equatorial Pacific, with the node crossing at a location in between Darwin and Tahiti denoted by the arrow. All the other factors scale from the temporal to spatial domain accordingly (via the fixed k term).
Thus, when I do the time-domain fit of ENSO while keeping track of all terms a,b,... , the spatial result is automatically set in place, apart from aligning the phase and selecting the spatial scaling factor k.
This is an initial stab at a spatially aligned fit of the generated standing wave as a [Hovmoller diagram](https://en.wikipedia.org/wiki/Hovm%C3%B6ller_diagram), with the left side measurements from  and the right side the model:
The node is right around 160E. The faster cycles in the model are what I think are related to the formation of Tropical Instability Waves, which has some character of a traveling wave. Will see if any of that fine structure is revealed in the other sources of data.
 Pinker, R. T., S. A. Grodsky, B. Zhang, A. Busalacchi, and W. Chen. “ENSO Impact on Surface Radiative Fluxes as Observed from Space: ENSO IMPACT ON SURFACE RADIATIVE FLUXES.” Journal of Geophysical Research: Oceans 122, no. 10 (October 2017): 7880–96. https://doi.org/10.1002/2017JC012900.
A possible source of the fine structure via ocean currents, from https://earth.nullschool.net/#current/ocean/surface/currents/orthographic=-158.02,2.78,819
If the data is available, a Hovmoller diagram could be created from a time-series sequence