The role of equatorial Rossby waves in westerly wind bursts

Tropospheric equatorially trapped Rossby waves interact with the Madden-Julian Oscillation (MJO) to modulate the development of westerly wind bursts and oceanic Kelvin waves. We show that the phase relationship between the active convective phase of the MJO over the West Pacific and the Equatorial Rossby waves modulates the duration and intensity of westerly wind bursts. This allows the Rossby waves to modulate the amplitudes of oceanic Kelvin waves and the remote east Pacific sea surface temperature response to the MJO. Thus, the Rossby waves help determine whether a period of MJO activity results in warming of the East Pacific.