🌊 ENSO Recharge Oscillator Lab: Bjerknes Feedback, Thermocline Heat Content and the El Nino - La Nina Phase Portrait

A two-variable recharge-oscillator model of El Nino and La Nina: sea-surface temperature and Pacific heat content chase each other round a phase portrait. Tune Bjerknes feedback, discharge damping, ocean adjustment speed and random wind bursts, and compare the measured period and growth rate with the exact eigenvalues.