Microbaroms are infrasonic waves generated by nonlinear interactions of ocean surface waves traveling in nearly opposite directions with similar frequencies. Such interactions commonly occur between ocean waves with ∼10 s periods, which are abundant in the open oceans and correspond to the observed 0.2 Hz infrasonic spectral peak. Microbarom observations from Hawai'i during 2002–2003 show a relationship with storm and ocean wave activity in the Pacific. Seasonal patterns of observed microbarom arrival azimuths are affected by the size and distribution of swells, by the dominant wind directions in the atmosphere, and by topographic shadowing.

The arrival azimuths of coherent microbarom signals observed in Hawaii during 2003 are associated with high ocean wave activity in the Pacific Basin, the dominant wind directions in the troposphere, stratosphere, and mesosphere, and the thermal structure of the atmosphere. Some of the seasonal trends in the microbarom observations can be explained by the winds in the stratosphere and lower mesosphere, while some of the daily variability can be explained by the winds in the troposphere and lower stratosphere. However, coherent energy from powerful swells may overcome the wind‐carried microbarom signals and arrive to the station through thermospheric ducting. Our observations suggest that either (1) the wind speeds in the troposphere, stratosphere and mesosphere may be underestimated in atmospheric models or (2) elevated leaky infrasonic waveguides are persistent propagation paths that should be investigated in more detail.

Comparison of ocean buoy measurements with infrasonic array data collected during the epic winter of 2002–2003 shows a clear relationship between breaking ocean wave height and infrasonic signal levels. In addition, infrasonic arrays allow the identification of distinct breaking zones along the shoreline. Our observations suggest that infrasonic measurements can be used in conjunction with buoys to estimate wave heights, identify regions of high wave action, and validate surface wave propagation models.