Orbits in phase space

Plot the atmosphere's angular-momentum anomaly against its tendency and the days trace loops: the Global Wind Oscillation of Weickmann & Berry. Counter-clockwise orbits carry the circulation between El Niño-like high-momentum states (phases 6–7) and La Niña-like low ones (phases 2–3), with a typical period of 30–60 days. At the end the orbit blooms into tomorrow: a linear inverse model's ensemble, the closest past trajectories, and GEFS when it has run.

GWO1 = standardized anomaly of global relative AAM; GWO2 = standardized anomaly of its tendency (5-day smoothing); octants as in Wheeler & Hendon (2004). The faint cloud is every day since 1979.

Space plays or pauses; ← → step; Shift+← → take big steps; hover to read any day. Every frame has its own link (Share), the image downloads at print size, and the whole piece can be embedded anywhere — it updates itself every day.