−10 −5 0 5 10 −10 −5 0 5 10 Poynting vector for synthetic ULF wave events GSM x (Re) GSM y (Re) −5 0 5 x 10−7 −5 −4 −3 −2 −1 0 1 2 3 4 5 W/m2 W/ m 2 Direction and magnitude of Poynting vector for events in grey box x 10−7 Probability density of Poynting vectors vs. GSM xy direction and magnitude 1x10-6 W/m2 1x10-9 W/m2 1x10-12 W/m2 Probability Density (sums to 1) 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 1 2 3